OLIVETOLIC ACID CYCLASE VARIANTS WITH IMPROVED ACTIVITY FOR USE IN PRODUCTION OF PHYTOCANNABINOIDS

Information

  • Patent Application
  • 20220170055
  • Publication Number
    20220170055
  • Date Filed
    November 20, 2020
    3 years ago
  • Date Published
    June 02, 2022
    2 years ago
Abstract
The present disclosure relates generally to methods, isolated polypeptides and polynucleotides, expression vectors, and host cells for the production of olivetolic acid and phytocannabinoids. A method of producing olivetolic acid (OVLa) and/or a phytocannabinoid in a heterologous host cell having OVLa-producing or phytocannabinoid-producing capacity comprises transforming the host cell with a nucleotide encoding a variant olivetolic acid cyclase (OAC) protein having at least 6 amino acid mutations relative to the wild type OAC protein, and culturing the transformed host cell to produce OVLa and/or phytocannabinoids therefrom. The variant OAC protein (SEQ ID NO:92) has at least 85% sequence identity with the wild type OAC protein (SEQ ID NO:91). Exemplary variants having improved OVLa or phytocannabinoid production capacity are described.
Description
CROSS REFERENCE TO RELATED APPLICATIONS

None.


FIELD

The present disclosure relates generally to proteins having olivetolic acid cyclase activity, useful in production of phytocannabinoids.


BACKGROUND

Phytocannabinoids are a large class of compounds with over 100 different known structures that are produced in the Cannabis sativa plant. Phytocannabinoids are known to be biosynthesized in C. sativa, or may result from thermal or other decomposition from phytocannabinoids biosynthesized in C. sativa. These bio-active molecules, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), can be extracted from plant material for medical and recreational purposes. However, the synthesis of plant material is costly, not readily scalable to large volumes, and requires lengthy growing periods to produce sufficient quantities of phytocannabinoids. While the C. sativa plant is also a valuable source of grain, fiber, and other material, growing C. sativa for phytocannabinoid production, particularly indoors, is costly in terms of energy and labour. Subsequent extraction, purification, and fractionation of phytocannabinoids from the C. sativa plant is also labour and energy intensive.


Phytocannabinoids are pharmacologically active molecules that contribute to the medical and psychotropic effects of C. sativa. Biosynthesis of phytocannabinoids in the C. sativa plant scales similarly to other agricultural projects. As with other agricultural projects, large scale production of phytocannabinoids by growing C. sativa requires a variety of inputs (e.g. nutrients, light, pest control, CO, etc.). The inputs required for cultivating C. sativa must be provided. In addition, cultivation of C. sativa, where allowed, is currently subject to heavy regulation, taxation, and rigorous quality control where products prepared from the plant are for commercial use, further increasing costs.


Phytocannabinoid analogues are pharmacologically active molecules that are structurally similar to phytocannabinoids. Phytocannabinoid analogues are often synthesized chemically, which can be labour intensive and costly. As a result, it may be economical to produce the phytocannabinoids and phytocannabinoid analogues in a robust and scalable, fermentable organism. Saccharomyces cerevisiae is an example of a fermentable organism that has been used to produce industrial scales of similar molecules.


The extensive time, energy, and labour involved in growing C. sativa for production of naturally-occurring phytocannabinoids provides a motivation to produce transgenic cell lines for production of phytocannabinoids by other means. Polyketides, including olivetolic acid and its analogues are valuable precursors to phytocannabinoids.


It is desirable to find alternative enzymes and methods for the production of phytocannabinoids, and/or for the production of compounds useful in phytocannabinoid biosynthesis as intermediate or precursor compounds.


SUMMARY

Olivetolic Acid Cyclase (OAC) variants are described herein which are capable of producing olivetolic acid (OVLa). These variants are useful in the production of olivetolic acid and relevant phytocannabinoids in a heterologous host. Methods of production are described. The described OAC variants that can produce olivetolic acid and downstream metabolites in a modified yeast cell can be applied to any host and used in phytocannabinoid production.


In certain aspects described, OAC variants comprise 6 or greater non-conservative substitution amino acid mutations relative to the wild type enzyme. Certain OAC variants described have improved activity and/or show improved ratios of olivetol to olivetolic acid compared to the wild type enzyme.


A method of producing OVLa or a phytocannabinoid derived therefrom in a heterologous host cell having OVLa-producing or phytocannabinoid-producing capacity is described. The method comprises: transforming the host cell with a nucleotide encoding a variant olivetolic acid cyclase (OAC) protein having at least 6 amino acid mutations relative to the wild type OAC protein, and culturing said transformed host cell to produce olivetolic acid and/or phytocannabinoids therefrom, wherein the variant OAC protein comprises at least 85% sequence identity with the wild type OAC protein sequence according to SEQ ID NO:91.


An isolated polypeptide having olivetolic acid cyclase activity is described, comprising an amino acid sequence according to SEQ ID NO: 92, wherein 6 or more amino acid residues comprise mutations relative to SEQ ID NO:91, located at 6 or more of residues 28, 31, 41, 43, 44, 68, 74, 84, 100 or 102 of SEQ ID NO:91.


An isolated polynucleotide is described, comprising: (a) a nucleotide sequence according to SEQ ID NO:3-SEQ ID NO:39; (b) a nucleotide sequence having at least 85% identity with the nucleotide sequence of (a), or (c) a nucleotide sequence that hybridizes with the complementary strand of the nucleotide having the sequence of (a). Expression vectors comprising the polynucleotide, and host cells transformed with such expression vectors are described.


Other aspects and features of the present disclosure will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments in conjunction with the accompanying figures.





BRIEF DESCRIPTION OF THE FIGURES

Embodiments of the present disclosure will now be described, by way of example only, with reference to the attached Figures.



FIG. 1 illustrates a cannabinoid biosynthesis pathway in Cannabis sativa.



FIG. 2 illustrates a cannabinoid biosynthesis pathway as described in Applicant's co-pending International Application No. PCT/CA2020/050687.



FIG. 3 illustrates PCR primers used in site-saturation mutagenesis protocol.



FIG. 4 shows an overlap-extension approach that was used to assemble mutagenic oligonucleotides for combinatorial library construction. The symbol x represents a point mutation.



FIG. 5 shows olivetolic acid production with mutant OAC variants.





DETAILED DESCRIPTION

A method of producing olivetolic acid (OVLa) or a phytocannabinoid produced therefrom is described herein. A heterologous host cell comprising OVLa-producing or phytocannabinoid-producing capacity is transformed with a nucleotide encoding a variant olivetolic acid cyclase (OAC) protein having at least 6 amino acid mutations relative to the wild type OAC protein and culturing said transformed host cell to produce olivetolic acid and/or phytocannabinoids therefrom, wherein the variant OAC protein comprises at least 85% sequence identity with the wild type OAC protein sequence according to SEQ ID NO: 91. Exemplary variant proteins may result in improved OVLa or phytocannabinoid production over wild type according to the method described.


In some embodiments, at least 4 of the at least 6 amino acid mutations of the OAC protein are in residues 28, 31, 41, 43, 44, 68, 74, 84, 100 or 102 of the wild type OAC protein (SEQ ID NO:91), with other mutations being located elsewhere in the sequence. When a mutation is present at residue 28, 31, 41, 43, 44, 68, 74, 84, 100 or 102, it can be either a conservative or non-conservative amino acid substitution, but may advantageously be a non-conservative amino acid substitution. While at least 4 of the 6 amino acid mutations are present in the specified residue locations, in exemplary embodiments, more than 4 may be present in the specified residues, such as 6, 7, 8, 9 or 10 of the amino acid mutations may be found at positions 28, 31, 41, 43, 44, 68, 74, 84, 100 or 102, relative to the wild type sequence. In certain embodiments, mutations other than those located at residue 28, 31, 41, 43, 44, 68, 74, 84, 100 or 102 may be limited to conservative amino acid substitutions, such that the variant OAC protein remains within 85% sequence identity with the wild type OAC protein.


The method may encompass transformation of the host cell with a nucleotide encoding the variant olivetolic acid cyclase (OAC) protein, which nucleotide has a sequence comprising: (a) a nucleotide sequence according to SEQ ID NO:3-SEQ ID NO:39; (b) a nucleotide sequence having at least 85% identity with the sequence of (a); or (c) a nucleotide sequence that hybridizes with the complementary strand of the nucleotide having the sequence of (a). For example, the variant OAC protein may comprise a according to any one of SEQ ID NO:40 to SEQ ID NO:76.


In certain embodiments, at least 4 of the at least 6 amino acid mutations relative to the wild type OAC protein are selected from the group consisting of: V28A; V31G; Y41T, Y41S or Y41V; K44V; T68L or T68R; I74E, I74R, I74D or I74G; V84R; R100M or R100E; and G102R, G102S, or G102STOP.


In the method, the production of a phytocannabinoid by the transformed host cell may involve production of phytocannabinoids including but not limited to cannabigerol (CBG), cannabigerolic acid (CBGa), cannabigerovarin (CBGV), cannabigerovarinic acid (CBGVa), cannabigerocin (CBGO), cannabigerocinic acid (CBGOa), a cannabivarin, tetrahydrocannabinol (THC), or tetrahydrocannabinolic acid (THCa). Further, using the OAC variants described, in combination with a divarinic acid synthase within the host cell, the host cell may produce a cannabivarin, such as divarinic acid.


The host cell transformed in the method described may be a bacterial cell, a fungal cell, a protist cell, or a plant cell. Exemplary organisms include S. cerevisiae, E. coli, Yarrowia lipolytica, or Komagataella phaffii, as well as others described herein. The transformed host cell may additionally comprise, or be transformed with, other enzymes useful in phytocannabinoid production. For example, a polynucleotide encoding a polyketide synthase enzyme and/or a polynucleotide encoding a prenyltransferase enzyme may also be included in the host cell. Further options for polynucleotides and methods, such as described in Applicant's co-pending International Application No. PCT/CA2020/050687 (hereby incorporated by reference) are envisioned.


An isolated polypeptide is described herein, which has olivetolic acid cyclase (OAC) activity. The polypeptide activity comprises an amino acid sequence according to SEQ ID NO: 92, wherein 6 or more amino acid residues comprise mutations relative to SEQ ID NO: 91 (wild type OAC) which are mutations at residues 28, 31, 41, 43, 44, 68, 74, 84, 100 or 102 of SEQ ID NO:91. The isolated polypeptide may have an amino acid sequence according to one of SEQ ID NO:40 to SEQ ID NO:76.


An isolated polynucleotide is described, which may have (a) a nucleotide sequence according to SEQ ID NO:3-SEQ ID NO:39; (b) a nucleotide sequence having at least 85% identity with the nucleotide sequence of (a), or (c) a nucleotide sequence that hybridizes with the complementary strand of the nucleotide having the sequence of (a).


An expression vector is described, comprising a polynucleotide encoding a variant olivetolic acid cyclase (OAC) protein having the sequence of SEQ ID NO: 92, in which 6 or more amino acid mutations are present relative to the wild type OAC protein. In such an expression vector, the polynucleotide encoding the variant OAC protein may have at least 85% sequence identity with any one of SEQ ID NO:3 to SEQ ID NO:39.


A host cell transformed with the above-described expression vector is also encompassed herein. Such a host cell may additionally comprise a polynucleotide encoding other enzymes useful in synthesis of olivetolic acid and/or phytocannabinoids, such as encoding a polyketide synthase enzyme and/or a prenyltransferase enzyme. Such a host cell may be a bacterial cell, a fungal cell, a protist cell, or a plant cell, for example: S. cerevisiae, E. coli, Yarrowia lipolytica, or Komagataella phaffii.


Definitions

Certain terms used herein are described below.


The term “cannabinoid” as used herein refers to a chemical compound that shows direct or indirect activity at a cannabinoid receptor. Non limiting examples of cannabinoids include tetrahydrocannabinol (THC), cannabidiol (CBD), cannabinol (CBN), cannabigerol (CBG), cannabichromene (CBC), cannabicyclol (CBL), cannabivarin (CBV), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), cannabichromevarin (CBCV), cannabigerovarin (CBGV), and cannabigerol monomethyl ether (CBGM).


The term “phytocannabinoid” as used herein refers to a cannabinoid that typically occurs in a plant species. Exemplary phytocannabinoids produced according to the invention include cannabigerol (CBG), cannabigerolic acid (CBGa), cannabigerovarin (CBGV), cannabigerovarinic acid (CBGVa), cannabigerocin (CBGo), or cannabigerocinic acid (CBGoa).


Cannabinoids and phytocannabinoids may contain or may lack one or more carboxylic acid functional groups. Non limiting examples of such cannabinoids or phytocannabinoids containing carboxylic acid function groups or phytocannabinoids include tetrahydrocannabinolic acid (THCA), cannabidiolic acid (CBDA), and cannabichromenic acid (CBCA).


The term “homologue” includes homologous sequences from the same and other species and orthologous sequences from the same and other species. Different polynucleotides or polypeptides having homology may be referred to as homologues.


The term “homology” may refer to the level of similarity between two or more polynucleotide and/or polypeptide sequences in terms of percent of positional identity (i.e., sequence similarity or identity). Homology also refers to the concept of similar functional properties among different polynucleotide or polypeptides. Thus, the compositions and methods herein may further comprise homologues to the polypeptide and polynucleotide sequences described herein.


The term “orthologous,” as used herein, refers to homologous polypeptide sequences and/or polynucleotide sequences in different species that arose from a common ancestral gene during speciation.


As used herein, a “homologue” may have a significant sequence identity (e.g., 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% and/or 100%) to the polynucleotide sequences herein.


As used herein “sequence identity” refers to the extent to which two optimally aligned polynucleotide or peptide sequences are invariant throughout a window of alignment of components, e.g., nucleotides or amino acids. “Identity” can be readily calculated by known methods.


As used herein, the term “percent sequence identity” or “percent identity” refers to the percentage of identical nucleotides in a linear polynucleotide sequence of a reference (“query”) polynucleotide molecule (or its complementary strand) as compared to a test (“subject”) polynucleotide molecule (or its complementary strand) when the two sequences are optimally aligned. In some embodiments, “percent identity” can refer to the percentage of identical amino acids in an amino acid sequence.


The terms “fatty acid-CoA”, “fatty acyl-CoA”, or “CoA donors” as used herein may refer to compounds useful in polyketide synthesis as primer molecules which react in a condensation reaction with an extender unit (such as malonyl-CoA) to form a polyketide. Examples of fatty acid-CoA molecules (also referred to herein as primer molecules or CoA donors), useful in the synthetic routes described herein include but are not limited to: acetyl-CoA, butyryl-CoA, hexanoyl-CoA. These fatty acid-CoA molecules may be provided to host cells or may be synthesized by the host cells for biosynthesis of polyketides, as described herein.


Two nucleotide sequences can be considered to be substantially “complementary” when the two sequences hybridize to each other under stringent conditions. In some examples, two nucleotide sequences considered to be substantially complementary hybridize to each other under highly stringent conditions.


The terms “stringent hybridization conditions” and “stringent hybridization wash conditions” in the context of nucleic acid hybridization experiments, for example in Southern hybridizations and Northern hybridizations are sequence dependent, and are different under different environmental parameters. In some examples, generally, highly stringent hybridization and wash conditions are selected to be about 5° C. lower than the thermal melting point (Tm) for the specific sequence at a defined ionic strength and pH.


In some examples, polynucleotides include polynucleotides or “variants” having at least about 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99% or 100% sequence identity to any of the reference sequences described herein, typically where the variant maintains at least one biological activity of the reference sequence.


As used herein, the terms “polynucleotide variant” and “variant” and the like refer to polynucleotides displaying substantial sequence identity with a reference polynucleotide sequence or polynucleotides that hybridize with a reference sequence under, for example, stringent conditions. These terms may include polynucleotides in which one or more nucleotides have been added or deleted, or replaced with different nucleotides compared to a reference polynucleotide. It will be understood that that certain alterations inclusive of mutations, additions, deletions and substitutions can be made to a reference polynucleotide whereby the altered polynucleotide retains the biological function or activity of the reference polynucleotide.


In some examples, the polynucleotides described herein may be included within “vectors” and/or “expression cassettes”.


In some embodiments, the nucleotide sequences and/or nucleic acid molecules described herein may be “operably” or “operatively” linked to a variety of promoters for expression in host cells. Thus, in some examples, the invention provides transformed host cells and transformed organisms comprising the transformed host cells, wherein the host cells and organisms are transformed with one or more nucleic acid molecules/nucleotide sequences of the invention. As used herein, “operably linked to,” when referring to a first nucleic acid sequence that is operably linked to a second nucleic acid sequence, means a situation when the first nucleic acid sequence is placed in a functional relationship with the second nucleic acid sequence. For instance, a promoter is operably associated with a coding sequence if the promoter effects the transcription or expression of the coding sequence.


In the context of a polypeptide, “operably linked to,” when referring to a first polypeptide sequence that is operably linked to a second polypeptide sequence, refers to a situation when the first polypeptide sequence is placed in a functional relationship with the second polypeptide sequence.


The term a “promoter,” as used herein, refers to a nucleotide sequence that controls or regulates the transcription of a nucleotide sequence (i.e., a coding sequence) that is operably associated with the promoter. Typically, a “promoter” refers to a nucleotide sequence that contains a binding site for RNA polymerase II and directs the initiation of transcription. In general, promoters are found 5′, or upstream, relative to the start of the coding region of the corresponding coding sequence. The promoter region may comprise other elements that act as regulators of gene expression.


Promoters can include, for example, constitutive, inducible, temporally regulated, developmentally regulated, chemically regulated, tissue-preferred and tissue-specific promoters for use in the preparation of recombinant nucleic acid molecules, i.e., chimeric genes.


The choice of promoter will vary depending on the temporal and spatial requirements for expression, and also depending on the host cell to be transformed. Thus, for example, where expression in response to a stimulus is desired a promoter inducible by stimuli or chemicals can be used. Where continuous expression at a relatively constant level is desired throughout the cells or tissues of an organism a constitutive promoter can be chosen.


In some examples, vectors may be used.


In some examples, the polynucleotide molecules and nucleotide sequences described herein can be used in connection with vectors.


The term “vector” refers to a composition for transferring, delivering or introducing a nucleic acid or polynucleotide into a host cell. A vector may comprise a polynucleotide molecule comprising the nucleotide sequence(s) to be transferred, delivered or introduced. Non-limiting examples of general classes of vectors include, but are not limited to, a viral vector, a plasmid vector, a phage vector, a phagemid vector, a cosmid, a fosmid, a bacteriophage, or an artificial chromosome. The selection of a vector will depend upon the preferred transformation technique and the target species for transformation.


As used herein, “expression vectors” refers to a nucleic acid molecule comprising a nucleotide sequence of interest, wherein said nucleotide sequence is operatively associated with at least a control sequence (e.g., a promoter). Thus, some examples provide expression vectors designed to express the polynucleotide sequences of described herein.


An expression vector comprising a polynucleotide sequence of interest may be “chimeric”, meaning that at least one of its components is heterologous with respect to at least one of its other components. An expression cassette may also be one that is naturally occurring but has been obtained in a recombinant form useful for heterologous expression. In some examples, however, the expression vector is heterologous with respect to the host. For example, the particular polynucleotide sequence of the expression vector does not occur naturally in the host cell and must have been introduced into the host cell or an ancestor of the host cell by a transformation event.


In some examples, an expression vector may also include other regulatory sequences. As used herein, “regulatory sequences” means nucleotide sequences located upstream (5′ non-coding sequences), within or downstream (3′ non-coding sequences) of a coding sequence, and which influence the transcription, RNA processing or stability, or translation of the associated coding sequence. Regulatory sequences include, but are not limited to, promoters, enhancers, introns, 5′ and 3′ untranslated regions, translation leader sequences, termination signals, and polyadenylation signal sequences.


An expression vector may also include a nucleotide sequence for a selectable marker, which can be used to select a transformed host cell.


As used herein, “selectable marker” means a nucleotide sequence that when expressed imparts a distinct phenotype to the host cell expressing the marker and thus allows such transformed host cells to be distinguished from those that do not have the marker. Such a nucleotide sequence may encode either a selectable or screenable marker, depending on whether the marker confers a trait that can be selected for by chemical means, such as by using a selective agent (e.g., an antibiotic, a sugar, a carbon source, or the like), or on whether the marker is simply a trait that one can identify through observation or testing, such as by screening. Examples of suitable selectable markers are known in the art and can be used in the expression vectors described herein.


The vector and/or expression vectors and/or polynucleotides may be introduced in to a cell.


The term “introducing,” in the context of a nucleotide sequence of interest (e.g., the nucleic acid molecules/constructs/expression vectors), refers to presenting the nucleotide sequence of interest to cell host in such a manner that the nucleotide sequence gains access to the interior of a cell. Where more than one nucleotide sequence is to be introduced these nucleotide sequences can be assembled as part of a single polynucleotide or nucleic acid construct, or as separate polynucleotide or nucleic acid constructs, and can be located on the same or different transformation vectors. Accordingly, these polynucleotides may be introduced into host cells in a single transformation event, or in separate transformation events.


As used herein, the term “contacting” refers to a process by which, for example, a compound may be delivered to a cell. The compound may be administered in a number of ways, including, but not limited to, direct introduction into a cell (i.e., intracellularly) and/or extracellular introduction into a cavity, interstitial space, or into the circulation of the organism.


The term “transformation” or “transfection” as used herein refers to the introduction of a polynucleotide or heterologous nucleic acid into a cell. Transformation of a cell may be stable or transient.


The term “transient transformation” as used herein in the context of a polynucleotide refers to a polynucleotide introduced into the cell and does not integrate into the genome of the cell.


The terms “stably introducing” or “stably introduced” in the context of a polynucleotide introduced into a cell is intended to represent that the introduced polynucleotide is stably incorporated into the genome of the cell, and thus the cell is stably transformed with the polynucleotide.


The term “host cell” includes an individual cell or cell culture which can be or has been a recipient of any recombinant vector(s) or isolated polynucleotide of the invention. Host cells include progeny of a single host cell, and the progeny may not necessarily be completely identical (in morphology or in total DNA complement) to the original parent cell due to natural, accidental, or deliberate mutation and/or change. A host cell includes cells transformed in vivo or in vitro with a recombinant vector or a polynucleotide of the invention. A host cell which comprises a recombinant vector of the invention is a recombinant host cell.


In some examples, a host cell may be a bacterial cell, a fungal cell, a protist cell, or a plant cell. Specific examples of host cells are described below.


“Conversion” refers to the enzymatic transformation of a substrate to the corresponding product. “Percent conversion” refers to the percent of the substrate that is converted to the product within a period of time under specified conditions. Thus, for example, the “activity” or “conversion rate” of a ketoreductase polypeptide can be expressed as “percent conversion” of the substrate to the product.


“Hydrophilic Amino Acid or Residue” refers to an amino acid or residue having a side chain exhibiting a hydrophobicity of less than zero according to the normalized consensus hydrophobicity scale Eisenberg et al., 1984. Genetically encoded hydrophilic amino acids include L-Thr (T), L-Ser (S), L-His (H), L-Glu (E), L-Asn (N), L-Gln (Q), L-Asp (D), L-Lys (K) and L-Arg (R).


“Acidic Amino Acid or Residue” refers to a hydrophilic amino acid or residue having a side chain exhibiting a pKa value of less than about 6 when the amino acid is included in a peptide or polypeptide. Acidic amino acids typically have negatively charged side chains at physiological pH due to loss of a hydrogen ion. Genetically encoded acidic amino acids include L-Glu (E) and L-Asp (D).


“Basic Amino Acid or Residue” refers to a hydrophilic amino acid or residue having a side chain exhibiting a pKa value of greater than about 6 when the amino acid is included in a peptide or polypeptide. Basic amino acids typically have positively charged side chains at physiological pH due to association with hydronium ion. Genetically encoded basic amino acids include L-Arg (R) and L-Lys (K).


“Polar Amino Acid or Residue” refers to a hydrophilic amino acid or residue having a side chain that is uncharged at physiological pH, but which has at least one bond in which the pair of electrons shared in common by two atoms is held more closely by one of the atoms. Genetically encoded polar amino acids include L-Asn (N), L-Gln (Q), L-Ser (S) and L-Thr (T).


“Hydrophobic Amino Acid or Residue” refers to an amino acid or residue having a side chain exhibiting a hydrophobicity of greater than zero according to the normalized consensus hydrophobicity scale (Eisenberg et al., 1984). Genetically encoded hydrophobic amino acids include L-Pro (P), L-Ile (I), L-Phe (F), L-Val (V), L-Leu (L), L-Trp (W), L-Met (M), L-Ala (A) and L-Tyr (Y).


“Aromatic Amino Acid or Residue” refers to a hydrophilic or hydrophobic amino acid or residue having a side chain that includes at least one aromatic or heteroaromatic ring. Genetically encoded aromatic amino acids include L-Phe (F), L-Tyr (Y) and L-Trp (V). Although owing to the pKa of its heteroaromatic nitrogen atom L His (H) it is sometimes classified as a basic residue, or as an aromatic residue as its side chain includes a heteroaromatic ring, herein histidine is classified as a hydrophilic residue.


“Constrained amino acid or residue” refers to an amino acid or residue that has a constrained geometry. Herein, constrained residues include L-Pro (P) and L-His (H). Histidine has a constrained geometry because it has a relatively small imidazole ring. Proline has a constrained geometry because it also has a five membered ring.


“Non-polar Amino Acid or Residue” refers to a hydrophobic amino acid or residue having a side chain that is uncharged at physiological pH and which has bonds in which the pair of electrons shared in common by two atoms is generally held equally by each of the two atoms (i.e., the side chain is not polar). Genetically encoded non-polar amino acids include L-Gly (G), L-Leu (L), L-Val (V), L-Ile (I), L-Met (M) and L-Ala (A).


“Aliphatic Amino Acid or Residue” refers to a hydrophobic amino acid or residue having an aliphatic hydrocarbon side chain. Genetically encoded aliphatic amino acids include L-Ala (A), L-Val (V), L-Leu (L) and L-Ile (I).


“Small Amino Acid or Residue” refers to an amino acid or residue having a side chain that is composed of a total three or fewer carbon and/or heteroatoms (excluding the α-carbon and hydrogens). The small amino acids or residues may be further categorized as aliphatic, non-polar, polar or acidic small amino acids or residues, in accordance with the above definitions. Genetically-encoded small amino acids include L-Ala (A), L-Val (V), L-Cys (C), L-Asn (N), L-Ser (S), L-Thr (T) and L-Asp (D).


A “conservative” amino acid substitution (or mutation) refers to the substitution of a residue with a residue having a similar side chain, and thus typically involves substitution of the amino acid in the polypeptide with amino acids within the same or similar defined class of amino acids. For the following residues, the possible conservative mutations are provided in parentheses: A, L, V, I (Other aliphatic residues: A, L, V, I); A, L, V, I, G, M (Other non-polar residues: A, L, V, I, G, M); D, E (Other acidic residues: D, E); K, R (Other basic residues: K, R); P, H (Other constrained residues: P, H); N, Q, S, T (Other polar residues: N, Q, S, T); Y, W, F (Other aromatic residues: Y, W, F); and C (none).


Phytocannabinoids are a large class of compounds with over 100 different known structures that are produced in the Cannabis plant. These bio-active molecules, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), can be extracted from plant material for medical and psychotropic purposes. However, the synthesis of plant material is costly, not readily scalable to large volumes, and requires lengthy growth periods to produce sufficient quantities of phytocannabinoids. A fermentable organism such as Saccharomyces cerevisiae capable of producing cannabinoids would provide an economical route to producing these compounds on an industrial scale. The extensive time, energy, and labour involved in growing C. sativa for phytocannabinoid production provides a motivation to produce transgenic cell lines for production of phytocannabinoids in yeast. One example of such efforts is provided in PCT application by Mookerjee et al WO2018/148848. Aromatic prenyltransferase from cannabis are described by Page et al. in U.S. Pat. No. 8,884,100.



FIG. 1 illustrates a cannabinoid biosynthesis pathway in Cannabis sativa. As expression and functionality of the C. sativa pathway in S. cerevisiae is hindered by problems of toxic precursors and poor expression, a novel biosynthetic route for cannabinoid production was developed that overcomes said issues. This pathway is described in FIG. 1 and comprises a multi-enzyme system. DiPKS from D. discoideum and OAC from C. sativa are used to produce olivetolic acid directly from glucose. GPP from the yeast terpenoid pathway and OLA are subsequently converted to cannabigerolic acid catalyzed by using a prenyltransferase. Then, C. sativa THCa synthase or CBDa synthase is used to further cyclize cannabigerolic acid to form THCa or CBDa respectively.



FIG. 2 illustrates a cannabinoid biosynthesis pathway as described in Applicant's co-pending PCT Application No. CA2020/050687 (Bourgeois et al., filed May 21, 2019), which is herein incorporated by reference.


The first committed step in the cannabinoid biosynthesis pathway is the biosynthesis of olivetolic acid. This is done using a polyketide synthase such as DiPKS (Ghosh et al., 2008) from D. discoideum or OAS (Taura et al., 2009) from C. sativa and also requires the use of an olivetolic acid cyclase (OAC) (Gagne et al., 2012). The process begins with the polyketide synthase condensing three units of malonyl-CoA to form a linear tetraketide. Olivetolic acid cyclase can then cyclize the tetraketide backbone to form olivetolic acid. In the absence of OAC, the tetraketide can spontaneously cyclize to form olivetol, an unwanted byproduct in the cannabinoid biosynthesis pathway. In order to improve enzyme performance in a heterologous host, the authors subjected OAC to an enzyme engineering regimen.


Enzyme engineering is the process of improving a desired phenotype of the enzyme by making modifications to the amino acid sequence of the polypeptide. As the functionality of the enzyme is dependent on the structure of the enzyme and the structure of the enzyme is dependent, partially, on the primary amino acid sequence; modification of the amino acid sequence of the enzyme could lead to a beneficial impact on the desired phenotype. This principle was applied to olivetolic acid cyclase (OAC) and modifications were made to its amino acid sequence using a directed evolution approach. This allowed for the identification of amino acid residues that improved olivetolic acid production in a strain of recombinant S. cerevisiae. Beneficial mutations were then tested in conjunction to identify combinations of mutations that improve enzyme performance.


Sequences are described herein that have multiple residues modified as compared to the wild type OAC sequence. Certain mutations produce over 2× more olivetolic acid than the wild type OAC when expressed in S. cerevisiae. Improvements to one or more enzyme properties as exhibited in the engineered OACs may include increases in enzyme activity, improved enzyme kinetics and turnover, higher tolerance to increased levels of substrate, and improved tolerance to increased product levels.


The modifications of the amino acid residues, as compared to the wild type OAC sequence may be conservative modifications or non-conservative modifications. Insertions or deletions may be used to modify the residues, relative to wild type OAC. Note that in the OAC described herein, the protein may end at position 101 instead of 102, as in other reports of wild type OAC sequences. In embodiments described herein, the residues represented as X{#} may be modified, where {#} represents the sequence position in the amino acid position of the wild type OAC sequence referenced herein as (SEQ ID NO:91). Thus, SEQ ID NO:92 comprises the option of mutations at X{28}, X{31}, X{41}, X{43}, X{44}, X{68}, X{74}, X{84}, X{100}, and X{102}, as outlined below:


SEQ ID NO:91 represents wild type OAC protein:











MAVKHLIVLK FKDEITEAQK EEFFKTYVNL VNIIPAMKDV YWGKDVTQKN
50






KEEGYTHIVE VTFESVETIQ DYIIHPAHVG FGDVYRSFWE KLLIFDYTPR
100





KG
102






SEQ ID NO:92 represents the generalized variant OAC protein, wherein X represents candidate locations for mutated residues (where X represents any amino acid):











MAVKHLIVLK FKDEITEAQK EEFFKTYXNL XNIIPAMKDV XWXXDVTQKN
50






KEEGYTHIVE VTFESVEXIQ DYIXHPAHVG FGDXYRSFWE KLLIFDYTPX
100





KX
102






Materials and Methods:


Genetic Manipulations:


Vector VB40 was used to construct all expression plasmids encoding enzyme proteins disclosed herein, including OAC and variants.


The OAC variants were constructed in a combinatorial library using mutations that were initially selected in a site-saturation mutagenesis library screen. Plasmid VB40_OAC was used as the template in all library construction.


Site-saturation mutagenesis was conducted at each amino acid position by a PCR reaction using a forward degenerate NNK primer and a ‘back-to-back’ reverse non-mutagenic primer (FIG. 3). The PCR products were then processed through in vitro kinase-ligase-DpnI reactions and transformed into Escherichia coli DH5alpha strain for amplification.



FIG. 3 illustrates PCR primers used in site-saturation mutagenesis protocol. Right-facing arrows represents forward degenerate NNK primer, symbol * denotes the mutational position, and the left-facing arrows represent reverse primer designed ‘back-to-back’ in the opposite direction of the forward primer.


The combinatorial library was constructed by an in-house protocol. Selected mutations were combined through an overlap-extension PCR of a batch of mutagenic oligonucleotides that were generated using targeted mutagenic primers. (FIG. 4). Double-stranded DNA of the assembled combinatorial mutant variants were cloned into a vector with complementary overlapping sequences, which resulted in a pool of OAC combinatorial variants. FIG. 4 shows an overlap-extension assembly of mutagenic oligonucleotides for combinatorial library construction. The symbol x represents a point mutation.


The plasmids encoding OAC and variant proteins as disclosed herein were transformed and expressed in Saccharomyces cerevisiae, with the host strain HB1416. All DNA was transformed into background strains using the Gietz et al. transformation protocol (Gietz 2014).


Strain Growth and Media:


Strains were grown in yeast synthetic complete media with a composition of 1.7 g/L YNB without ammonium sulfate, 1.92 g/L URA dropout amino acid supplement, 1.5 g/L magnesium L-glutamate, with 2% w/v galactose, 2% w/v raffinose, 200 μg/l geneticin, and 200 μg/L ampicillin (Sigma-Aldrich Canada). The culture was incubated at 30° C. for four days (96 hours). Strain HB1891 and HB1892 were respectively used as wild type control and negative control in all of the screenings.


Variant Screening Conditions:


Each variant was tested in three replicates and each replicate was clonally derived from single colonies. All strains were grown in 500 μl of media for 96 hours in 96-well deepwell plates. The 96-well deepwell plates were incubated at 30° C. and shaken at 950 rpm for 96 hrs.


Metabolite extraction was performed by adding 30 μl of culture to 270 μl of 56% acetonitrile in a new 96-well microtiter plate. The solutions were mixed thoroughly, then centrifuged at 3750 rpm for 10 mins. 200 μl of the soluble layer was removed and stored in a 96-well v-bottom microtiter plate. Samples were stored at −20° C. until analysis.


Quantification Protocol:


The quantification of olivetolic acid was performed using HPLC-MS/MS on a Waters Acquity UPLC-TQD MS. The chromatography and MS conditions are described below.


HPLC Conditions


Column: ACQUITY HSS C18 UPLC 50×1 mm, 1.8 μm particle size (PN:186003529); Column temperature: 45° C.; Flow rate: 0.350 mL/min; Eluent A: Water+0.1% Formic Acid; Eluent B: Acetonitrile+0.1% Formic Acid; Gradient is shown in Table 1.









TABLE 1







Gradient










Time (min)
% B














0
20



0.60
98



1.10
98



1.11
20



1.60
20










ESI-MS Conditions


The following conditions were utilized: Capillary: 2.90 (kV); Source temperature: 150° C.; Desolvation gas temperature: 250° C.; Desolvation gas flow (nitrogen): 500 L/hour; Cone gas flow (nitrogen): 1 L/hour; Detection parameters are shown in Table 2.









TABLE 2







Detection Parameters












OVLa
OVL
CBGa
THCa














Retention time (min)
0.70
0.72
0.98
1.12


Parent (m/z)
223.0
181.1
359.2
357.2


Daughter (m/z)
179.0
71.0
341.2
313.2


Mode
ES−,
ES+,
ES−,
ES−,



MRM
MRM
MRM
MRM


Cone (V)
35
20
40
45


Collision (V)
20
12
25
30









Strains used are described in Table 3.









TABLE 3







Strains Used











Strain #
Background
Plasmids
Genotype
Notes





HB1416
-URA, -LEU
None

Saccharomyces cerevisiae

Parent strain for





CEN.PK2; ΔLEU2; ΔURA3; Erg2
olivetolic acid





0K197E::KanMx; ALD6; ASC1L6
production





41P; NPGA; MAF1; PGK1p:Acc1;
screen





tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



HB1891
-URA, -LEU
PLAS-417

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
OAC; positive





0K197E::KanMx; ALD6; ASC1L6
control for





41P; NPGA; MAF1; PGK1p:Acc1;
olivetolic acid





tHMGR1; IDI; DiPKS_G1516R X
production





5; ACC1_S659A_S1157A; UB14
screen





p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



HB1892
-URA, -LEU
PLAS-416

Saccharomyces cerevisiae

Expresses non-





CEN.PK2; ΔLEU2; ΔURA3; Erg2
catalytic





0K197E::KanMx; ALD6; ASC1L6
mScarlet;





41P; NPGA; MAF1; PGK1p:Acc1;
negative control





tHMGR1; IDI; DiPKS_G1516R X
for olivetolic





5; ACC1_S659A_S1157A; UB14
acid production





p:ERG20; PT254-R2S; Ost1-
screen





pro-alpha-f(I)-OXC53



PLT1577-D10
-URA, -LEU
PLAS-527

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-D12
-URA, -LEU
PLAS-528

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-B9
-URA, -LEU
PLAS-529

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-C12
-URA, -LEU
PLAS-530

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-D2
-URA, -LEU
PLAS-531

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1572-B10
-URA, -LEU
PLAS-532

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-A9
-URA, -LEU
PLAS-533

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1577-D1
-URA, -LEU
PLAS-534

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1577-B7
-URA, -LEU
PLAS-535

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-F8
-URA, -LEU
PLAS-536

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1574-H11
-URA, -LEU
PLAS-537

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-E1
-URA, -LEU
PLAS-538

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-G1
-URA, -LEU
PLAS-539

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-A2
-URA, -LEU
PLAS-540

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-B10
-URA, -LEU
PLAS-541

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-D7
-URA, -LEU
PLAS-542

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-H10
-URA, -LEU
PLAS-543

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1574-F5
-URA, -LEU
PLAS-544

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-D8
-URA, -LEU
PLAS-545

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1574-A11
-URA, -LEU
PLAS-546

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1574-B9
-URA, -LEU
PLAS-547

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-B5
-URA, -LEU
PLAS-548

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-F2
-URA, -LEU
PLAS-549

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1572-H10
-URA, -LEU
PLAS-550

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-E12
-URA, -LEU
PLAS-551

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-D12
-URA, -LEU
PLAS-552

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-B8
-URA, -LEU
PLAS-553

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-A2
-URA, -LEU
PLAS-554

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-B4
-URA, -LEU
PLAS-555

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1573-G12
-URA, -LEU
PLAS-556

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-G12
-URA, -LEU
PLAS-557

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-H5
-URA, -LEU
PLAS-558

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-A6
-URA, -LEU
PLAS-559

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1576-D1
-URA, -LEU
PLAS-560

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1572-E8
-URA, -LEU
PLAS-561

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1572-H9
-URA, -LEU
PLAS-562

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53



PLT1575-F9
-URA, -LEU
PLAS-563

Saccharomyces cerevisiae

Expresses





CEN.PK2; ΔLEU2; ΔURA3; Erg2
mutant OAC





0K197E::KanMx; ALD6; ASC1L6






41P; NPGA; MAF1; PGK1p:Acc1;






tHMGR1; IDI; DiPKS_G1516R X






5; ACC1_S659A_S1157A; UB14






p:ERG20; PT254-R2S; Ost1-






pro-alpha-f(I)-OXC53









The following plasmids were used, as described in Table 4.









TABLE 4







Plasmids











#
Plasmid Name
SEQ ID NO.
Description
Selection














1
PLAS-416
001
Gal1p:mScarlet:Cyc1t
Uracil


2
PLAS-417
002
Gal1p:OAC:Cyc1t
Uracil


3
PLAS-527
003
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/T68L/
Uracil





I74E/V84 R/R100M/G102R: Cyc1t



4
PLAS-528
004
Gal1p:OAC-
Uracil





Y41S/G43SILENT(=GGG)/K44V/T68R/






I74R/V84R:Cyc1t



5
PLAS-529
005
Gal1p:OAC-
Uracil





V28A/V31G/Y41S/G43SILENT(=GGG)/






K44V/T68L/I74R/V84R/R100E/






G102R:Cyc1t



6
PLAS-530
006
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/T68L/






I74G/V84R/R100E:Cyc1t



7
PLAS-531
007
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/K44V/






T68L/I74D/V84R/R100M/G10






2R:Cyc1t



8
PLAS-532
008
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/T68L/






I74D/V84R/G102R:Cyc1t



9
PLAS-533
009
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/K44V/






T68L/I74R/V84R/R100E/G10R:Cyc1t
Uracil


10
PLAS-534
010
Gal1p:OAC-






Y41T/G43SILENT(=GGG)/T68R/I74R/






V84R/R100M/G102STOP:Cyc1t



11
PLAS-535
011
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/K44V/






T68L/I74G/V84R/R100E/G102R:Cyc1t



12
PLAS-536
012
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/K44V/






T68R/I74G/V84R/G102STOP: Cyc1t



13
PLAS-537
013
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/K44V/






T68L/I74R/V84R/R100E/ G102STOP:Cyc1t



14
PLAS-538
014
Gal1p:OAC-
Uracil





V28A/V31G/Y41T/G43SILENT(=GGG)/






K44V/T68R/I74E/V84R/R100E:Cyc1t



15
PLAS-539
015
Gal1p:OAC-
Uracil





V28A/Y41S/G43SILENT(=GGG)/T68R/






I74R/V84R/R100M/G102STOP:Cyc1t



16
PLAS-540
016
Gal1p:OAC-
Uracil





Y41T/G43SILENT(=GGG)/K44V/T68L/






I74G/V84R/G102R:Cyc1t



17
PLAS-541
017
Gal1p:OAC-
Uracil





V28A/Y41T/G43SILENT(=GGG)/K44V/






T68R/I74R/V84R/R100E/G102R:Cyc1t



18
PLAS-542
018
Gal1p:OAC-
Uracil





V28A/V31G/Y41S/G43SILENT(=GGG)/






K44V/T68R/I74 R/V84 R: Cyc1t



19
PLAS-543
019
Gal1p:OAC-
Uracil





V28A/G43SILENT(=GGG)/K44V/I74D/






V84R/R100E/G102R(=CGC): Cyc1t



20
PLAS-544
020
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/K44V/






T68L/I74G/V84RIG102 R: Cyc1t



21
PLAS-545
021
Gal1p:OAC-
Uracil





Y41T/G43SILENT(=GGG)/T68L/I74G/






V84R/R100M/G102 R:Cyc1t



22
PLAS-546
022
Gal1p:OAC-
Uracil





V28A/V31G/Y41T/G43SILENT(=GGG)/






K44V/T68R/I74R/V84R/R100E/






G102R:Cyc1t



23
PLAS-547
023
Gal1p:OAC-
Uracil





V31G/Y41S/G43SILENT(=GGG)/






K44V/T68R/V84R/R100E:Cyc1t



24
PLAS-548
024
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/T68L/






I74D/R100E/G102STOP:Cyc1t



25
PLAS-549
025
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/T68R/






I74G/V84 R/R100M/G 102R: Cyc1t



26
PLAS-550
026
Gal1p:OAC-
Uracil





V31G/G43SILENT(=GGG)/I74G/V84R/






R100E:Cyc1t



27
PLAS-551
027
Gal1p:OAC-
Uracil





V28A/Y41S/G43SILENT(=GGG)/K44V/






T68R/I74R/V84 R/R100M/G102R:Cyc1t



28
PLAS-552
028
Gal1p:OAC-
Uracil





V28A/V31G/Y41V/G43SILENT(=GGG)/






K44V/T68UI74G/V84R: Cyc1t



29
PLAS-553
029
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/K44V/






T68L/I74G/V84R/R100M/G102R:Cyc1t



30
PLAS-554
030
Gal1p:OAC-
Uracil





V28A/V31G/G43SILENT(=GGG)/T68L/






I74R/V84R/R100E/G102R:Cyc1t



31
PLAS-555
031
Gal1p:OAC-
Uracil





V31G/Y41V/G43SILENT(=GGG)/






K44V/T68L/I 74R/V84 R/R100 E/G102STOP: Cyc1t



32
PLAS-556
032
Gal1p:OAC-
Uracil





V31G/Y41T/G43SILENT(=GGG)/K44V/






T68 R/I74D/V84R/G 102 R: Cyc1t



33
PLAS-557
033
Gal1p:OAC-
Uracil





V31G/Y41T/G43SILENT(=GGG)/K44V/






T68R/174D/V84R/R100 E/G102R:Cyc1t



34
PLAS-558
034
Gal1p:OAC-
Uracil





V28A/Y41S/G43SILENT(=GGG)/K44V/






T68R/I74G/V84 R/R100M/G102R:Cyc1t



35
PLAS-559
035
Gal1p:OAC-
Uracil





V28A/Y41V/G43SILENT(=GGG)/K44V/






I74R/R100E/G102STOP:Cyc1t



36
PLAS-560
036
Gal1p:OAC-
Uracil





V28A/V31G/Y41T/G43SILENT(=GGG)/






K44V/I74E/V84R/R100M/G102R:Cyc1t



37
PLAS-561
037
Gal1p:OAC-
Uracil





V28A/G43SILENT(=GGG)/K44V/T68R/






I74E/V84R/R100E/G102STOP:Cyc1t



38
PLAS-562
038
Gal1p:OAC-
Uracil





V31G/Y41T/G43SILENT(=GGG)/K44V/






T68L/I74D/V84R/G102R:Cyc1t



39
PLAS-563
039
Gal1p:OAC-
Uracil





Y41V/G43SILENT(=GGG)/K44V/T 68L/






I74R/V84R/G102R:Cyc1t









The following sequences are described herein (Table 5)









TABLE 5







Sequences
















Length
Position of


SEQ ID
Plasmid

DNA/
of
coding


NO:
Name
Description
Protein
sequence
sequence















001
PLAS-416
Gal1p:mScarlet:Cyclt
DNA
6114
2649 to 3347


002
PLAS-417
Gal1p:OAC:Cyc1t
DNA
5724
2649 to 2957


003
PLAS-527
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41T/







G43SILENT(=GGG)/







T68L/I74E/V84R/







R100M/G102R:Cyc1t





004
PLAS-528
Gal1p:OAC-
DNA
5724
2648 to 2957




Y41S/







G43SILENT(=GGG)/







K44V/T68R/







I74R/V84R:Cyc1t





005
PLAS-529
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/Y41S/







G43SILENT(=GGG)/







K44V/T68L/







I74R/V84R/R100E/







G102R:Cyc1t





006
PLAS-530
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41T/







G43SILENT(=GGG)/







T68L/I74G/V84R/







R100E:Cyc1t





007
PLAS-531
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68L/I74D/







V84R/R100M/







G102R:Cyc1t





008
PLAS-532
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41T/







G43SILENT(=GGG)/







T68L/I74D/V84R/







G102R:Cyc1t





009
PLAS-533
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68L/I74R/







V84R/R100E/







G102R:Cyc1t





010
PLAS-534
Gal1p:OAC-
DNA
5724
2648 to 2954




Y41T/







G43SILENT(=GGG)/







T68R/I74R/







V84R/R100/







G102STOP:Cyc1t





011
PLAS-535
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74G/







V84R/R100E/G102R:Cyc1t





012
PLAS-536
Gal1p:OAC-
DNA
5724
2648 to 2954




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74G/







V84R/G102STOP:Cyc1t





013
PLAS-537
Gal1p:OAC-
DNA
5724
2648 to 2954




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74R/







V84R/R100E/







G102STOP:Cyc1t





014
PLAS-538
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/







I74E/V84R/







R100E:Cyc1t





015
PLAS-539
Gal1p:OAC-
DNA
5724
2648 to 2954




V28A/Y41S/







G43SILENT(=GGG)/







T68R/I74R/V84R/







R100M/







G102STOP:Cyc1t





016
PLAS-540
Gal1p:OAC-
DNA
5724
2648 to 2957




Y41T/







G43SILENT(=GGG)/







K44V/T68L/







I74G/V84R/







G102R:Cyc1t





017
PLAS-541
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74R/







V84R/R100E/







G102R:Cyc1t





018
PLAS-542
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/Y41S/







G43SILENT(=GGG)/







K44V/T68R/







I74R/V84R:Cyc1t





019
PLAS-543
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/







G43SILENT(=GGG)/







K44V/I74D/







V84R/R100E/







G102R(=CGC):Cyc1t





020
PLAS-544
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74G/







V84R/G102R:Cyc1t





021
PLAS-545
Gal1p:OAC-
DNA
5724
2648 to 2957




Y41T/







G43SILENT(=GGG)/







T68L/I74G/







V84R/R100M/







G102R:Cyc1t





022
PLAS-546
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/







I74R/V84R/R100E/







G102R:Cyc1t





023
PLAS-547
Gal1p:OAC-
DNA
5724
2648 to 2957




V31G/Y41S/







G43SILENT(=GGG)/







K44V/T68R/V84R/







R100E:Cyc1t





024
PLAS-548
Gal1p:OAC-
DNA
5724
2648 to 2954




V28A/Y41V/







G43SILENT(=GGG)/







T68L/I74D/R100E/







G102STOP:Cyc1t





025
PLAS-549
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41V/







G43SILENT(=GGG)/







T68R/I74G/V84R/







R100M/G102R: Cyc1t





026
PLAS-550
Gal1p:OAC-
DNA
5724
2648 to 2957




V31G/







G43SILENT(=GGG)/







I74G/V84R/







R100E:Cyc1t





027
PLAS-551
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41S/







G43SILENT(=GGG)/







K44V/T68RI74R/







V84R/R100M/







G102R:Cyc1t





028
PLAS-552
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74G/







V84R:Cyc1t





029
PLAS-553
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74G/







V84R/R100M/







G102R:Cyc1t





030
PLAS-554
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/







G43SILENT(=GGG)/







T68L/I74R/V84R/







R100E/G102R:Cyc1t





031
PLAS-555
Gal1p:OAC-
DNA
5724
2648 to 2954




V31G/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74R/







V84R/R100E/







G102STOP:Cyc1t





032
PLAS-556
Gal1p:OAC-
DNA
5724
2648 to 2957




V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74D/







V84R/G102R:Cyc1t





033
PLAS-557
Gal1p:OAC-
DNA
5724
2648 to 2957




V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74D/







V84R/R100E/







G102R:Cyc1t





034
PLAS-558
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/Y41S/







G43SILENT(=GGG)/







K44V/T68R/I74G/







V84R/R100M/







G102R:Cyc1t





035
PLAS-559
Gal1p:OAC-
DNA
5724
2648 to 2954




V28A/Y41V/







G43SILENT(=GGG)/







K44V/I74R/R100E/







G102STOP:Cyc1t





036
PLAS-560
Gal1p:OAC-
DNA
5724
2648 to 2957




V28A/V31G/Y41T/







G43SILENT(=GGG)/







K44V/I74E/







V84R/R100M/







G102R:Cyc1t





037
PLAS-561
Gal1p:OAC-
DNA
5724
2648 to 2954




V28A/







G43SILENT(=GGG)/







K44V/T68R/







I74E/V84R/







R100E/G102STOP:Cyc1t





038
PLAS-562
Gal1p:OAC-
DNA
5724
2648 to 2957




V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68L/I74D/







V84R/G102R:Cyc1t





039
PLAS-563
Gal1p:OAC-
DNA
5724
2648 to 2957




Y41V/







G43SILENT(=GGG)/







K44V/T68L/







I74R/V84R/







G102R:Cyclt





40
PLAS-527
Gal1p:OAC-
Protein
102
All




V28A/Y41T/







G43SILENT(=GGG)/







T68L/I74E/V84R/







R100M/G102R:Cyc1t





41
PLAS-528
Gal1p:OAC-
Protein
102
All




Y41S/







G43SILENT(=GGG)/







K44V/T68R/







I74R/V84R:Cyc1t





42
PLAS-529
Gal1p:OAC-
Protein
102
All




V28A/V31G/Y41S/







G43SILENT(=GGG)/







K44V/T68L/







I74R/V84R/R100E/







G102R: Cyc1t





43
PLAS-530
Gal1p:OAC-
Protein
102
All




V28A/Y41T/







G43SILENT(=GGG)/







T68L/I74G/V84R/







R100E:Cyc1t





44
PLAS-531
Gal1p:OAC-
Protein
102
All




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68L/I74D/







V84R/R100M/







G102R:Cyc1t





45
PLAS-532
Gal1p:OAC-
Protein
102
All




V28A/Y41T/







G43SILENT(=GGG)/







T68L/I74D/V84R/







G102R:Cyc1t





46
PLAS-533
Gal1p:OAC-
Protein
102
All




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68L/I74R/







V84R/R100E/







G102R:Cyc1t





47
PLAS-534
Gal1p:OAC-
Protein
101
All




Y41T/







G43SILENT(=GGG)/







T68R/I74R/







V84R/R100M/







G102STOP:Cyc1t





48
PLAS-535
Gal1p:OAC-
Protein
102
All




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74G/







V84R/R100E/







G102R:Cyc1t





49
PLAS-536
Gal1p:OAC-
Protein
101
All




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74G/







V84R/G102STOP:Cyc1t





50
PLAS-537
Gal1p:OAC-
Protein
101
All




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74R/







V84R/R100E/







G102STOP:Cyc1t





51
PLAS-538
Gal1p:OAC-
Protein
102
All




V28A/V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/







I74E/V84R/R100E: Cyclt





52
PLAS-539
Gal1p:OAC-
Protein
101
All




V28A/Y41S/







G43SILENT(=GGG)/







T68R/I74R/V84R/







R100M/G102STOP:Cyc1t





53
PLAS-540
Gal1p:OAC-
Protein
102
All




Y41T/







G43SILENT(=GGG)/







K44V/T68L/







I74G/V84R/







G102R:Cyc1t





54
PLAS-541
Gal1p:OAC-
Protein
102
All




V28A/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74R/







V84R/R100E/







G102R:Cyc1t





55
PLAS-542
Gal1p:OAC-
Protein
102
All




V28A/V31G/Y41S/







G43SILENT(=GGG)/







K44V/T68R/







I74R/V84R:Cyc1t





56
PLAS-543
Gal1p:OAC-
Protein
102
All




V28A/







G43SILENT(=GGG)/







K44V/I74D/







V84R/R100E/







G102R(=CGC):Cyc1t





57
PLAS-544
Gal1p:OAC-
Protein
102
All




V28A/Y41V/G43







SILENT(=GGG)/







K44V/T68L/I74G/







V84R/G102R:Cyc1t





58
PLAS-545
Gal1p:OAC-
Protein
102
All




Y41T/







G43SILENT(=GGG)/







T68L/I74G/







V84R/R100M/







G102R:Cyc1t





59
PLAS-546
Gal1p:OAC-
Protein
102
All




V28A/V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/







I74R/V84R/R100E/







G102R:Cyc1t





60
PLAS-547
Gal1p:OAC-
Protein
102
All




V31G/Y41S/







G43SILENT(=GGG)/







K44V/T68R/V84R/







R100E:Cyc1t





61
PLAS-548
Gal1p:OAC-
Protein
101
All




V28A/Y41V/







G43SILENT(=GGG)/







T68L/I74D/R100E/







G102STOP:Cyc1t





62
PLAS-549
Gal1p:OAC-
Protein
102
All




V28A/Y41V/







G43SILENT(=GGG)/







T68R/I74G/V84R/







R100M/G102R:Cyc1t





63
PLAS-550
Gal1p:OAC-
Protein
102
All




V31G/







G43SILENT(=GGG)/







I74G/V84R/R100E:Cyc1t





64
PLAS-551
Gal1p:OAC-
Protein
102
All




V28A/Y41S/







G43SILENT(=GGG)/







K44V/T68R/I74R/







V84R/R100M/







G02R:Cyc1t





65
PLAS-552
Gal1p:OAC-
Protein
102
All




V28A/V31G/Y41V/







G43SILENT(=GGG)/







K44V/T68L/







I74G/V84R:Cyc1t





66
PLAS-553
Gal1p:OAC-
Protein
102
All




V28A/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74G/







V84R/R100M/







G02R:Cyc1t





67
PLAS-554
Gal1p:OAC-
Protein
102
All




V28A/V31G/







G43SILENT(=GGG)/







T68L/I74R/V84R/







R100E/G102R:Cyc1t





68
PLAS-555
Gal1p:OAC-
Protein
101
All




V31G/Y41V/







G43SILENT(=GGG)/







K44V/T68L/I74R/







V84R/R100E/







G102STOP:Cyc1t





69
PLAS-556
Gal1p:OAC-
Protein
102
All




V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74D/







V84R/G102R:Cyc1t





70
PLAS-557
Gal1p:OAC-
Protein
102
All




V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68R/I74D/







V84R/R100E/







G102R:Cyc1t





71
PLAS-558
Gal1p:OAC-
Protein
102
All




V28A/Y41S/







G43SILENT(=GGG)/







K44V/T68R/I74G/







V84R/R100M/







G102R:Cyc1t





72
PLAS-559
Gal1p:OAC-
Protein
101
All




V28A/Y41V/







G43SILENT(=GGG)/







K44V/I74R/R100E/







G102STOP:Cyc1t





73
PLAS-560
Gal1p:OAC-
Protein
102
All




V28A/V31G/Y41T/







G43SILENT(=GGG)/







K44V/I74E/







V84R/R100M/







G102R:Cyc1t





74
PLAS-561
Gal1p:OAC-
Protein
101
All




V28A/







G43SILENT(=GGG)/







K44V/T68R/







I74E/V84R/







R100E/







G102STOP:Cyc1t





75
PLAS-562
Gal1p:OAC-
Protein
102
All




V31G/Y41T/







G43SILENT(=GGG)/







K44V/T68L/I74D/







V84R/G102R:Cyc1t





76
PLAS-563
Gal1p:OAC-
Protein
102
All




Y41V/







G43SILENT(=GGG)/







K44V/T68L/







I74R/V84R/







G102R:Cyc1t





77

NpgA
DNA
3564
1170 - 2201


78

DiPKS-1
DNA
11114
849 - 10292


79

DiPKS-2
DNA
10890
717 - 10160


80

DiPKS-3
DNA
11300
795 - 10238


81

DiPKS-4
DNA
11140
794 - 10237


82

DiPKS-5
DNA
11637
1172 - 10615


83

PDH
DNA
7114
Ald6: 1444 -







2949







ACS: 3888 -







5843


84

Maf1
DNA
3256
936 - 2123


85

Erg20K197E
DNA
4254
2842 - 3900






(4538)



86

Erg1p:UB14-
DNA
3503
1364 - 2701




Erg20:deg





87

tHMGr-IDI
DNA
4843
tHMGR1: 885 -







2393







IDI1: 3209 -







4075


88

PGK1p:ACC1S659A, S1157A
DNA
7673
Pgk1p: 222 -







971







Acc1mut: 972 -







7673


89

PT254-R2S
DNA
4707
1957-2925


90

Ost1-pro-alpha-
DNA
4137
1615-3168




f(I)-OXC53





91
PLAS-417
Wild Type OAC
Protein
102
All


92
PLAS-417
Variant OAC
Protein
102
All


93
PLAS-416
mScarlet
Protein
232
All









Modifications to base strains used herein are outlined below in Table 6.









TABLE 6







Modifications to Base Strains














SEQ ID





#
Modification name
NO.
Integration Region/Plasmid
Description
Genetic Structure of Sequence















1
NpgA
77
Flagfeldt
Phosphopantetheinyl
Site14Up::Tef1p:





Site14
Transferase from Aspergillus
NpgA:Prm9t: Site





integration

niger. Accessory Protein for

14Down






DiPKS (Kim et al., 2015)



2
DiPKS-1
78
USER Site
Type 1 FAS fused to Type 3
XII-





XII-1
PKS from D. discoideum.
1up::Gal1p:DiPK





integration
Produces Olivetol from malonyl-
SG1516R:






coA
Prm9t::XII1-down


3
DiPKS-2
79
Wu site 1
Type 1 FAS fused to Type 3
Wu1up::Gal1t:





integration
PKS from D. discoideum.
DiPKSG1516R:






Produces Olivetol from malonyl-
Prm9t::Wu1down






coA



4
DiPKS-3
80
Wu site 3
Type 1 FAS fused to Type 3
Wu3up::Gal1p:





integration
PKS from D. discoideum.
DiPKSG1516R:






Produces Olivetol from malonyl-
Prm9t::Wu3down






coA



5
DiPKS-4
81
Wu site 6
Type 1 FAS fused to Type 3
Wu6up::Gal1p:





integration
PKS from D. discoideum.
DiPKSG1516R:






Produces Olivetol from malonyl-
Prm9t::Wu6down






coA



6
DiPKS-5
82
Wu site 18
Type 1 FAS fused to Type 3
Wu18up::Gal1p:





integration
PKS from D. discoideum.
DiPKSG1516R:






Produces Olivetol from malonyl-
Prm9t::Wu18down






coA



7
PDH
83
Flagfeldt
Acetaldehyde dehydrogenase
19Up::Tdh3p:Ald6:





Site 19
(ALD6) from S. cerevisiae and
Adh1::Tef1p:







seACS1L641P:





integration
acetoacetyl coA synthase
Prm9t::19Down






(AscL641P) from Salmonella








enterica. Will allow greater








accumulation of acetyl-coA in







the cell (Shiba et al., 2007).



8
Maf1
84
Flagfeldt
Maf1 is a regulator of tRNA
Site5Up::Tef1p:





Site 5
biosynthesis. Overexpression in
Maf1:Prm9t:Site





integration

S. cerevisiae has demonstrated

5Down






higher monoterpene (GPP)







yields (Liu et al., 2013).



9
Erg20K197E
85
Chromosomal
Mutant of Erg20 protein that
Tpi1t:ERG20K197E:





modification
diminishes FPP synthase
Cyc1t::Tef1p:






activity creating greater pool of
KanMX:Tef1t






GPP precursor. Negatively







affects growth phenotype







(Oswald et al., 2007).



10
Erg1p:UB14-
86
Flagfeldt
Sterol responsive promoter
Site18Up::Erg1p:



Erg20: deg

Site 18
controlling Erg20 protein
UB14deg:ERG20:





integration
activity. Allows for regular FPP
Adh1t:Site18down






synthase activity and uninhibited







growth phenotype until







accumulation of sterols which







leads to a suppression of







expression of enzyme (Peng et







al., 2018).



11
tHMGr-
87
USER Site
Overexpression of truncated
X3up::Tdh3p:



ID1

X-3
HMGr1 and IDI1 proteins that
tHMGR1:





integration
have been previously identified
Adh1t::Tef1p:IDI1:






to be bottlenecks in the S.
Prm9t::X3down







cerevisiae terpenoid pathway








responsible for GPP production







(Ro et al., 206).



12
PGK1p:
88
Chromosomal
Mutations in the native S.
Pgkt1:



ACC1S659A, S1157A

modification

cerevisiae acetyl-coA

ACC1S659A, S1157A:






carboxylase that removes post-
Acc1t






translational modification based







down-regulation. Leads to







greater malonyl-coA pools. The







promoter of Acc1 was also







changed to a constitutive







promoter for higher expression







(Shi et al., 2014).



13
PT254-
89
Flagfeldt
The Cannabis sativa
FgF18up::Tef1p:



R25

Site 18
prenyltransferase PT254 allows
R2S-





integration
CBGa to be produced from
PT254:Cyct::






olivetolic acid and geranyl
FgF20down






pyrophosphate (Luo et al.,







2019). The N terminal arginine







of this enzyme has been







replaced with a serine in order to







enhance protein stability in







accordance with N-end rule







(Varshaysky 1996).



14
Ost1-
90
Apel-3
ΔA28THCa synthase (OX053)
Apel3up::Tef1p:



pro-


from C. sativa. (Sirikantaramas
Ost1-pro-alpha-



f(I)-


et al., 2005). Fused with a Ost1-
f(I)-



alpha-


pro-alpha-f(I) tag. Produces
OXC53t:Cyct::



OXC53


THCa from CBGa
Apel3down






Results:


Identification of Variants that Demonstrate Improved Production of Olivetolic Acid (OVLa) and Downstream Cannabinoids


An OAC mutants library was constructed in a plasmid regulated by the Gal1p promoter, and expressed in an olivetol-producing background strain (HB1416) harboring downstream enzymes of the cannabinoid production pathway. The strains expressing wild type OAC (HB1891) and mScarlet fluorescent protein (HB1892) were utilized as control in the screening to facilitate identification of OAC mutant hits with improved activity.



FIG. 5 shows olivetolic acid production by engineered OACs strains. The measured values of each cannabinoid are shown in FIG. 5. The mutants tested had the silent mutation G43G(GGG) present, which is an artifact of the plasmid construction process and not relevant to increased enzyme performance.


Table 7 shows production of olivetol, olivetolic acid and downstream cannabinoids in OAC wild type and engineered OACs strains.









TABLE 7







Production of Olivetol, Olivetolic Acid and Downstream Cannabinoids




















Total









Down stream






Olivetolic


Metabolites
# of non-




Olivetol
Acid
CBGa
THCa
(OVLa, CBGa,
conserative


Strain
OAC mutant
(mg/L)
(mg/L)
(mg/L)
(mg/L)
THCa)
mutations

















HB1891
Wild type OAC
53.367
53.850
8.283
2.367
64.500
NA


HB1892
RFP negative --
84.833
5.717
0.517
0.150
6.383
NA



no OAC








PLT1577-D10
Gal1p: OAC-
70.633
110.800
13.933
2.700
127.433
6



V28A/Y41T/G43









SILENT(=GGG)/









T68L/I74E/V84R/









R100M/G102R:









Cyc1t








PLT1575-D12
Gal1p: OAC-
77.200
94.367
13.200
4.133
111.700
5



Y41S/G43SILENT









(=GGG)/K44V/









T68R/I74R/V84R:









Cyc1t








PLT1576-B9
Gal1p: OAC-
52.500
78.167
14.933
3.367
96.467
7



V28A/V31G/Y41S/









G43SILENT(=GGG)/









K44V/T68L/I74R/V84R/









R100E/G102R: Cyc1t








PLT1575-C12
Gal1p: OAC-
75.333
75.400
12.600
3.500
91.500
5



V28A/Y41T/G43









SILENT(=GGG)/









T68L/I74G/V84R/









R100E: Cyc1t








PLT1575-D2
Gal1p: OAC-
81.400
73.267
12.800
2.700
88.767
7



V28A/Y41T/G43









SILENT(=GGG)/









K44V/T68L/I74D/









V84R/R100M/









G102R: Cyc1t








PLT1572-B10
Gal1p: OAC-
45.433
72.400
8.433
2.867
83.700
5



V28A/Y41T/G43









SILENT(=GGG)/









T68L/I74D/V84R/









G102R: Cyc1t








PLT1576-A9
Gal1p: OAC-
66.633
69.767
10.800
2.733
83.300
7



V28A/Y41T/G43









SILENT(=GGG)/









K44V/T68L/I74R









V84R/R100E/









G102R: Cyc1t








PLT1577-D1
Gal1p: OAC-
71.567
68.833
12.933
2.967
84.733
5



Y41T/G43SILENT









(=GGG)/T68R/









I74R/V84R/R100M/









G102STOP: Cyc1t








PLT1577-B7
Gal1p: OAC-
77.800
68.800
10.767
2.533
82.100
7



V28A/Y41V/









G43SILENT(=GGG)/









K44V/T68L/I74G/V84R/









R100E/G102R: Cyc1t








PLT1575-F8
Gal1p: OAC-
81.667
68.533
12.167
3.067
83.767
5



V28A/Y41T/









G43SILENT(=GGG)/









K44V/T68R/I74G/V84R/









G102STOP: Cyc1t








PLT1574-H11
Gal1p: OAC-
72.833
67.200
11.533
3.333
82.067
6



V28A/Y41V/









G43SILENT(=GGG)/









K44V/T68L/I74R/









V84R/R100E/G









102STOP: Cyc1t








PLT1575-E1
Gal1p: OAC-
85.100
66.433
11.500
3.467
81.400
6



V28A/V31G/Y41T/









G43SILENT(=GGG)/









K44V/T68R/









I74E/V84R/R100E:









Cyc1t








PLT1575-G1
Gal1p: OAC-
71.200
64.200
9.300
2.367
75.867
5



V28A/Y41S/









G43SILENT(=GGG)/









T68R/I74R/V84R/









R100M/G102









STOP: Cyc1t








PLT1576-A2
Gal1p: OAC-
56.633
62.267
12.300
3.067
77.633
6



Y41T/G43SILENT









(=GGG)/K44V/









T68L/174G/V84R/









G102R: Cyc1t








PLT1576-B10
Gal1p: OAC-
63.633
61.600
12.533
2.967
77.100
7



V28A/Y41T/









G43SILENT(=GGG)/









K44V/T68R/I74R/









V84R/R100E/









G102R: Cyc1t








PLT1573-D7
Gal1p: OAC-
58.467
61.033
8.767
2.833
72.633
5



V28A/V31G/Y41S/









G43SILENT(=GGG)/









K44V/T68R/I74R/









V84R: Cyc1t








PLT1575-H10
Gal1p: OAC-
72.533
60.400
11.467
2.600
74.467
5



V28A/G43SILENT









(=GGG)/K44V/









I74D/V84R/R100E/









G102R(=CGC): Cyc1t








PLT1574-F5
Gal1p: OAC-
71.300
59.400
10.767
2.867
73.033
6



V28A/Y41V/









G43SILENT(=GGG)/









K44V/T68L/I74G/









V84R/G102R: Cyc1t








PLT1573-D8
Gal1p: OAC-
58.367
58.167
7.733
2.800
68.700
6



Y41T/G43SILENT









(=GGG)/T68









UI74G/V84R/R1









00M/G102R: Cyc1t








PLT1574-A11
Gal1p: OAC-
65.033
58.133
8.167
3.067
69.367
7



V28A/V31G/Y41T/









G43SILENT(=GGG)/









K44V/T68R/









I74R/V84R/R100E/









G102R: Cyc1t








PLT1574-B9
Gal1p: OAC-
75.800
57.133
9.600
2.700
69.433
5



V31G/Y41S/









G43SILENT(=GGG)/









K44V/T68R/V84R/









R100E: Cyc1t








PLT1576-B5
Gal1p: OAC-
72.900
55.833
9.900
2.467
68.200
4



V28A/Y41V/









G43SILENT(=GGG)/









T68L/174D/R100E/









G102STOP: Cyc1t








PLT1573-F2
Gal1p: OAC-
71.900
55.433
8.367
2.567
66.367
6



V28A/Y41V/









G43SILENT(=GGG)/









T68R/I74G/V84R/









R100M/G102R: Cyc1t








PLT1572-H10
Gal1p: OAC-V31G/
49.733
54.100
6.700
2.433
63.233
3



G43SILENT(=GGG)/









I74GA/84R/R100E: Cyc1t








PLT1573-E12
Gal1p: OAC-
56.833
54.000
7.100
2.433
63.533
7



V28A/Y41S/









G43SILENT(=GGG)/









K44V/T68R/I74R/









V84R/R100M/









G102R: Cyc1t








PLT1573-D12
Gal1p: OAC-
57.633
52.500
6.967
2.467
61.933
5



V28A/V31G/Y41V/









G43SILENT(=GGG)/









K44V/T68L/I74G/









V84R: Cyc1t








PLT1573-B8
Gal1p: OAC-
53.267
51.367
6.733
2.133
60.233
7



V28A/Y41V/









G43SILENT(=GGG)/









K44V/T68L/I74G/









V84R/R100M/









G102R: Cyc1t








PLT1573-A2
Gal1p: OAC-
66.700
49.600
6.900
2.467
58.967
5



V28A/V31G/









G43SILENT(=GGG)/









T68L/I74RA/84R/









R100E/G102R: Cyc1t








PLT1576-B4
Gal1p: OAC-
70.700
47.633
10.833
2.600
61.067
6



V31G/Y41V/









G43SILENT(=GGG)/









K44V/T68L/I74R/









V84R/R100E/









G102STOP: Cyc1t








PLT1573-G12
Gal1p: OAC-
71.933
46.133
7.600
2.400
56.133
6



V31G/Y41T/









G43SILENT(=GGG)/









K44V/T68R/I74D/









V84 R/G102R: Cyc1t








PLT1576-G12
Gal1p: OAC-
56.133
45.800
10.667
2.467
58.933
7



V31G/Y41T/









G43SILENT(=GGG)/









K44V/T68R/I74D/









V84R/R100E/









G102R: Cyc1t








PLT1575-H5
Gal1p: OAC-
59.733
44.533
10.500
2.467
57.500
7



V28A/Y41S/









G43SILENT(=GGG)/









K44V/T68R/I74G/









V84R/R100M/









G102R: Cyc1t








PLT1576-A6
Gal1p: OAC-
63.500
44.400
9.533
2.367
56.300
4



V28A/Y41V/









G43SILENT(=GGG)/









K44V/174R/R10









0E/G102STOP:









Cyc1t








PLT1576-D1
Gal1p: OAC-
67.767
41.500
9.867
2.533
53.900
6



V28A/V31G/Y41T/









G43SILENT(=GGG)/









K44V/I74E/









V84R/R100M/









G102R: Cyc1t








PLT1572-E8
Gal1p: OAC-V28A/
29.467
32.433
2.833
1.167
36.433
5



G43SILENT(=GGG)/









K44V/T68R/174E/









V84R/R100E/









G102STOP: Cyc1t








PLT1572-H9
Gal1p: OAC-
43.067
30.200
3.333
1.233
34.767
6



V31G/Y41T/









G43SILENT(=GGG)/









K44V/T68L/I74D/









V84R/G102R: Cyc1t








PLT1575-F9
Gal1p: OAC-
106.267
13.633
2.033
0.533
16.200
6



Y41V/G43SILENT









(=GGG)/K44V/









T68L/I74R/V84R/









G102R: Cyc1t









Table 8 illustrates the ratio of OVLa or downstream metabolites (CBGa, CBDa, THCa) to OVL in OAC variants.









TABLE 8







Ratio of OVLa or Downstream Metabolites (CBGa, CBDa, THCa) to OVL in OAC Variants













# of non-conservative
OVLa:OVL



Strain
OAC mutant
mutations
ratio
Total Downstream:OVL





HB1891
Wild type OAC
NA
1.105
1.301


HB1892
RFP negative:
NA
0.076
0.083



no OAC





PLT1577-D10
Gal1p:OAC-
6
1.569
1.804



V28A/Y41T/G43






SILENT(=GGG)/






T68L/I74E/V84R/






R100M/G102R:






Cyc1t





PLT1575-D12
Gal1p:OAC-
5
1.227
1.451



Y415/G43SI LENT(=GGG)/






K44V/






T68R/I74R/V84R:






Cyc1t





PLT1576-B9
Gal1p:OAC-
7
1.485
1.839



V28A/V31G/Y41S/






G43SILENT(=GGG)/






K44V/T68L/






I74R/V84R/R100E/






G102R:Cyc1t





PLT1575-C12
Gal1p:OAC-
5
1.003
1.218



V28A/Y41T/






G43SILENT(=GGG)/






T68L/I74G/V84R/






R100E: Cyc1t





PLT1575-D2
Gal1p:OAC-
7
0.901
1.091



V28A/Y41T/






G43SILENT(=GGG)/






K44V/T68L/I74D/






V84R/R100M/G102R:Cyc1t





PLT1572-B10
Gal1p:OAC-
5
1.609
1.856



V28A/Y41T/






G43SILENT(=GGG)/






T68L/I74D/V84R/






G102R:Cyc1t





PLT1576-A9
Gal1p:OAC-
7
1.053
1.259



V28A/Y41T/






G43SILENT(=GGG)/






K44V/T68L/I74R/






V84R/R100E/G102R:Cyc1t





PLT1577-D1
Gal1p:OAC-
5
0.961
1.184



Y41T/G43SILENT(=GGG)/






T68R/I74R/






V84R/R100M/






G102STOP:Cyc1t





PLT1577-B7
Gal1p:OAC-
7
0.907
1.084



V28A/Y41V/






G43SILENT(=GGG)/






K44V/T68L/I74G/






V84R/R100E/G102R:Cyc1t





PLT1575-F8
Gal1p:OAC-
5
0.839
1.027



V28A/Y41T/






G43SILENT(=GGG)/






K44V/T68R/I74G/






V84R/G102STOP:Cyc1t





PLT1574-H11
Gal1p:OAC-
6
0.929
1.136



V28A/Y41V/






G43SILENT(=GGG)/






K44V/T68L/I74R/






V84R/R100E/G102STOP:Cyc1t





PLT1575-E1
Gal1p:OAC-
6
0.783
0.959



V28A/V31G/Y41T/






G43SILENT(=GGG)/






K44V/T68R/






I74E/V84R/R100E:Cyc1t





PLT1575-G1
Gal1p:OAC-
5
0.904
1.068



V28A/Y41S/






G43SILENT(=GGG)/






T68R/I74R/V84R/






R100M/G102






STOP: Cyc1t





PLT1576-A2
Gal1p:OAC-
6
1.107
1.378



Y41T/G43SILENT(=GGG)/






K44V/T68L/I74G/V84R/






G102R:Cyc1t





PLT1576-B10
Gal1p:OAC-
7
0.981
1.227



V28A/Y41T/






G43SILENT(=GGG)/






K44V/T68R/I74R/






V84R/R100E/G102R:






Cyc1t





PLT1573-D7
Gal1p:OAC-
5
1.046
1.247



V28A/V31G/Y41S/






G43SILENT(=GGG)/






K44V/T68R/






I74R/V84R:Cyc1t





PLT1575-H10
Gal1p:OAC-
5
0.834
1.031



V28A/G43SILENT(=GGG)/






K44V/I74D/






V84R/R100E/






G102R(=CGC):Cyc1t





PLT1574-F5
Gal1p:OAC-
6
0.838
1.030



V28A/Y41V/G43






SILENT(=GGG)/






K44V/T68L/I74G/






V84R/G102R:Cyc1t





PLT1573-D8
Gal1p:OAC-
6
0.994
1.174



Y41T/G43SILENT(=GGG)/






T68L/I74G/V84R/R100M/






G102R:Cyc1t





PLT1574-A11
Gal1p:OAC-
7
0.890
1.061



V28A/V31G/Y41T/






G43SILENT(=GGG)/






K44V/T68R/






I74R/V84R/R100E/G102R:






Cyc1t





PLT1574-B9
Gal1p:OAC-
5
0.757
0.921



V31G/Y41S/






G43SILENT(=GGG)/






K44V/T68R/V84R/






R100E:Cyc1t





PLT1576-B5
Gal1p:OAC-
4
0.767
0.937



V28A/Y41V/






G43SILENT(=GGG)/






T68L/I74D/R100E/






G102STOP:Cyc1t





PLT1573-F2
Gal1p:OAC-
6
0.783
0.936



V28A/Y41V/






G43SILENT(=GGG)/






T68R/I74G/V84R/






R100M/G102R:






Cyc1t





PLT1572-H10
Gal1p:OAC-
3
1.102
1.287



V31G/G43SILENT(=GGG)/






I74G/V84R/






R100E:Cyc1t





PLT1573-E12
Gal1p:OAC-
7
0.951
1.119



V28A/Y41S/






G43SILENT(=GGG)/






K44V/T68R/I74R/






V84R/R100M/G102R:Cyc1t





PLT1573-D12
Gal1p:OAC-
5
1.082
1.267



V28A/V31G/Y41V/






G43SILENT(=GGG)/






K44V/T68L/






I74G/V84R:Cyc1t





PLT1573-B8
Gal1p:OAC-
7
0.986
1.152



V28A/Y41V/






G43SILENT(=GGG)/






K44V/T68L/I74G/






V84R/R100M/G102R:






Cyc1t





PLT1573-A2
Gal1p:OAC-
5
0.753
0.894



V28A/V31G//






G43SILENT(=GGG)






T68L/I74R/V84R/






R100E/G102R:






Cyc1t





PLT1576-B4
Gal1p:OAC-
6
0.679
0.873



V31G/Y41V/






G43SILENT(=GGG)/






K44V/T68L/I74R/






V84R/R100E/G102STOP:Cyc1t





PLT1573-G12
Gal1p:OAC-
6
0.638
0.777



V31G/Y41T/






G43SILENT(=GGG)/






K44V/T68R/I74D/






V84R/G102R:Cyc1t





PLT1576-G12
Gal1p:OAC-
7
0.824
1.064



V31G/Y41T/






G43SILENT(=GGG)/






K44V/T68R/I74D/






V84R/R100E/G102R:Cyc1t





PLT1575-H5
Gal1p:OAC-
7
0.748
0.966



V28A/Y41S/






G43SILENT(=GGG)/






K44V/T68R/I74G/






V84R/R100M/






G102R:Cyc1t





PLT1576-A6
Gal1p:OAC-
4
0.703
0.891



V28A/Y41V/






G43SILENT(=GGG)/






K44V/I74R/R100E/






G102STOP:Cyc1t





PLT1576-D1
Gal1p:OAC-
6
0.614
0.798



V28A/V31G/Y41T/






G43SILENT(=GGG)/






K44V/I74E/






V84R/R100M/






G102R:Cyc1t





PLT1572-E8
Gal1p:OAC-
5
1.101
1.236



V28A/G43SILENT(=GGG)/






K44V/T68R/






I74E/V84R/






R100E/G102STOP:Cyc1t





PLT1572-H9
Gal1p:OAC-
6
0.729
0.838



V31G/Y41T/






G43SILENT(=GGG)/






K44V/T68L/I74D/






V84R/G102R:Cyc1t





PLT1575-F9
Gal1p:OAC-
6
0.138
0.164



Y41V/G43SILENT(=GGG)/






K44V/T68L/






I74R/V84R/






G102R:Cyc1t









Table 9 provides a summary of mutational frequency data.









TABLE 9







Mutational Frequency Data














Total
Occurrences
Occurrences in
Occurrences in




occurrences
in best 10 improved
strains with
strains with




in sequence
olivetolic acid
improved total downstream
improved OVLa:OVL


Mutation
mutational type
set (/37)
producers (/10)
metabolites vs WT (/24)
ratios vs WT (/5)















V28A
Conservative
26
8
18
3


Y41T
Non-
16
7
12
3



conservative






T68L
Non-
18
7
12
4



conservative






I74E
Non-
4
1
2
1



conservative






V84R
Non-
35
10
22
5



conservative






R100M
Non-
10
3
6
1



conservative






G102R
Non-
22
6
13
5



conservative






K44V
Non-
27
6
15
3



conservative






T68R
Non-
15
3
10
1



conservative






V31G
Conservative
13
2
5
1


I74R
Non-
14
4
9
2



conservative






R100E
Non-
17
4
11
1



conservative






I74D
Non-
7
2
4
1



conservative






G102S
Non-
8
2
5
0



conservative






Y41S
Non-
7
1
5
2



conservative






Y41V
Non-
10
1
5
0



conservative






I74G
Conservative
11
3
7
2


G102STOP
Conservative
8
2
6
0


G43SILEN
Conservative
37
10
24
5


T(=GGG














Use in Host Cells


Phytocannabinoids, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), can be extracted from plant material for medical and psychotropic purposes. However, the synthesis of plant material is costly, not readily scalable to large volumes, and requires a lengthy grow periods to produce sufficient quantities of phytocannabinoids. An organism capable of fermentation, such as Saccharomyces cerevisiae, that is capable of producing cannabinoids would provide an economical route to producing these compounds on an industrial scale.


The early stages of the cannabinoid pathway proceeds via the generation of olivetolic acid by the type III PKS olivetolic acid synthase (OAS) and cyclase olivetolic acid cyclase (OAC). This reaction uses a hexanoyl-CoA starter as well as three units of malonyl-CoA. Olivetolic acid is the backbone of most classical cannabinoids and can be prenylated to form CBGA, which is ultimately converted to CBDA or THCA by an oxidocyclase. Production of olivetolic acid in S. cerevisiae is challenging as OAS generates significant by-products such as HTAL, PDAL and olivetol. These by-products can be reduced in a recombinant organism by the introduction of olivetolic acid cyclase (OAC) but even with this enzyme by-products can account for up to 80% of the total carbon in the reaction.


Table 10 lists specific examples of host cell organisms in which the described OAC variants may be utilized for preparation of cannabinoids in the described pathways.









TABLE 10







List of Host Cell Organisms








Type
Organisms





Bacteria

Escherichia coli, Streptomyces





coelicolor and other species., Bacillus





subtilis, Mycoplasma genitalium,





Synechocytis, Zymomonas mobilis,





Corynebacterium glutamicum,





Synechococcus sp., Salmonella typhi,





Shigella flexneri, Shigella sonnei,




and Shigella disenteriae, Pseudomonas




putida, Pseudomonas aeruginosa,





Pseudomonas mevalonii, Rhodobacter





sphaeroides, Rhodobacter capsulatus,





Rhodospirillum rubrum,
Rhodococcus sp.



Fungi

Saccharomyces cerevisiae, Ogataea polymorpha,





Komagataella phaffii,
Kluyveromyces lactis,





Neurospora crassa, Aspergillus niger, Aspergillus





nidulans, Schizosaccharomyces pombe, Yarrowia lipolytica,





Myceliophthora thermophila,





Aspergillus oryzae, Trichoderma reesei,





Chrysosporium lucknowense,





Fusarium sp., Fusarium gramineum,





Fusarium venenatum, Pichia finlandica,





Pichia trehalophila, Pichia
koclamae,





Pichia membranaefaciens, Pichia opuntiae, Pichia





thermotolerans, Pichia salictaria,





Pichia guercuum, Pichia pijperi, Pichia





stipitis, Pichia methanolica,





Hansenula polymorpha.



Protists

Chlamydomonas reinhardtii,





Dictyostelium discoideum, Chlorella sp.,





Haematococcus pluvialis, Arthrospira platensis, Dunaliella sp.,





Nannochloropsis oceanica.



Plants

Cannabis sativa, Arabidopsis thaliana,





Theobroma cacao, maize, banana,




peanut, field peas, sunflower, Nicotiana sp.,



tomato, canola, wheat, barley,






oats, potato, soybeans, cotton, sorghum, lupin, rice.









Phytocannabinoids may be produced in a host cell involving Dictyostelium discoideum polyketide synthase (DiPKS), olivetolic acid cyclase (OAC), prenyltransferases, and/or mutants of these, as described in Applicant's co-pending International Application No. PCT/CA2020/050687 (herein incorporated by reference). For example, a host cell transformed with a polyketide synthase coding sequence, an olivetolic acid cyclase coding sequence, and a prenyltransferase coding sequence may be prepared. The polyketide synthase and the olivetolic acid cyclase catalyze synthesis of olivetolic acid from malonyl CoA. The olivetolic acid cyclase may include wild type, or any of the functional mutants described herein. The host cell may include a yeast cell, a bacterial cell, a protest cell or a plant cell, selected from among those listed in Table 10.


Combinations of the methods, nucleotides, and expression vectors described herein as well as in Applicant's co-pending International Application No. PCT/CA2020/050687 may be employed together to produce phytocannabinoids, phytocannabinoid precursors such as polyketides. Depending on the desired product, selections of characteristics of the cells and methods employed may be selected to achieve production of the cannabinoid, cannabinoid precursor, or intermediate of interest.


Methods of producing a phytocannabinoid may comprising culturing a host cell under suitable culture conditions to form a phytocannabinoid, said host cell comprising: a polynucleotide encoding a polyketide synthase (PKS) enzyme; a polynucleotide encoding an olivetolic acid cyclase (OAC) enzyme mutants as described herein; and a polynucleotide encoding a prenyltransferase (PT) enzyme; and optionally comprising: a polynucleotide encoding an acyl-CoA synthase (Alk) enzyme; a polynucleotide encoding a fatty acyl CoA activating (CsAAE) enzyme; and/or a polynucleotide encoding a THCa synthase (OXC) enzyme.


An expression vector can be prepared comprising a polynucleotide encoding a polyketide synthase (PKS) enzyme; a polynucleotide encoding an olivetolic acid cyclase (OAC) enzyme mutants as described herein; and a polynucleotide encoding a prenyltransferase (PT) enzyme. The expression vector can optionally comprise a polynucleotide encoding an acyl-CoA synthase (Alk) enzyme; a polynucleotide encoding CsAAE1; and/or a polynucleotide encoding a THCa synthase (OXC) enzyme.


Examples Only

In the preceding description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the embodiments. However, it will be apparent to one skilled in the art that these specific details are not required.


The embodiments described herein are intended to be examples only. Alterations, modifications and variations can be effected to the particular embodiments by those of skill in the art. The scope of the claims should not be limited by the particular embodiments set forth herein, but should be construed in a manner consistent with the specification as a whole.


The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modification as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.


REFERENCES

All publications, patents and patent applications mentioned in this Specification are indicative of the level of skill those skilled in the art to which this invention pertains and are herein incorporated by reference to the same extent as if each individual publication patent, or patent application was specifically and individually indicated to be incorporated by reference.


Patent Publications



  • U.S. Pat. No. 7,361,482

  • U.S. Pat. No. 8,884,100 (Page et al.) Aromatic Prenyltransferase from Cannabis.

  • WO2018148848 (Mookerjee et al.) publication of PCT/CA2018/050189, METHOD AND CELL LINE FOR PRODUCTION OF PHYTOCANNABINOIDS AND PHYTOCANNABINOID ANALOGUES IN YEAST

  • WO2018148849 (Mookerjee et al.) publication of PCT/CA2018/050190, METHOD AND CELL LINE FOR PRODUCTION OF POLYKETIDES IN YEAST



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Claims
  • 1. A method of producing olivetolic acid (OVLa) or a phytocannabinoid produced therefrom in a heterologous host cell comprising OVLa-producing or phytocannabinoid-producing capacity, said method comprising: transforming said host cell with a nucleotide encoding a variant olivetolic acid cyclase (OAC) protein of at least 95% sequence identity with the amino acid sequence of SEQ ID NO:42, and having at least 6 amino acid mutations relative to the wild type OAC protein sequence of SEQ ID NO:91, said at least 6 mutations being selected from the group consisting of:V28A;V31G;Y41T, Y41S or Y41V;K44V;T68L or T68R;I74E, I74R, I74D or I74G;V84R;R100M or R100E; andG102R, or G102S,
  • 2. (canceled)
  • 3. (canceled)
  • 4. (canceled)
  • 5. The method of claim 1, wherein said variant OAC protein has 7, 8, or 9 amino acid mutations relative to the wild type OAC protein sequence of SEQ ID NO:91 selected from the group consisting of: V28A;V31G;Y41T, Y41S or Y41V;K44V;T68L or T68R;I74E, I74R, I74D or I74G;V84R;R100M or R100E; andG102R, or G102S.
  • 6. (canceled)
  • 7. The method according to claim 1, wherein the nucleotide encoding the variant olivetolic acid cyclase (OAC) protein has a sequence comprising: (a) a nucleotide sequence of SEQ ID NO:5; or(b) a nucleotide sequence having at least 95% sequence identity with the sequence of (a).
  • 8. The method according to claim 1, wherein the variant OAC protein comprises the sequence of SEQ ID NO: 42.
  • 9. (canceled)
  • 10. The method of claim 1, wherein said phytocannabinoid is cannabigerol (CBG), cannabigerolic acid (CBGa), cannabigerovarin (CBGV), cannabigerovarinic acid (CBGVa), cannabigerocin (CBGO), cannabigerocinic acid (CBGOa), a cannabivarin, tetrahydrocannabinol (THC), or tetrahydrocannabinolic acid (THCa).
  • 11. The method of claim 1, wherein the host cell additionally comprises a divarinic acid synthase and produces divarinic acid.
  • 12. (canceled)
  • 13. The method of claim 1, wherein said host cell is S. cerevisiae.
  • 14. The method of claim 1, wherein said transformed host cell additionally comprises a polynucleotide encoding a polyketide synthase enzyme or a polynucleotide encoding a prenyltransferase enzyme.
  • 15. (canceled)
  • 16. (canceled)
  • 17. (canceled)
  • 18. (canceled)
  • 19. (canceled)
  • 20. (canceled)
  • 21. (canceled)
  • 22. An isolated polypeptide having olivetolic acid cyclase (OAC) activity comprising an amino acid sequence of at least 95% sequence identity with the amino acid sequence of SEQ ID NO: 42, and having at least 6 amino acid mutations relative to the wild type OAC protein sequence of SEQ ID NO:91, said at least 6 mutations being selected from the group consisting of: V28A;V31G;Y41T, Y41S or Y41V;K44V;T68L or T68R;I74E, I74R, I74D or I74G;V84R;R100M or R100E; andG102R, or G102S.
  • 23. The isolated polypeptide of claim 22, wherein said variant OAC protein has 7, 8, or 9 of the amino acid mutations relative to the wild type OAC protein sequence.
  • 24. The isolated polypeptide of claim 22, having the amino acid sequence of SEQ ID NO:42.
  • 25. An isolated polynucleotide encoding the isolated polypeptide of claim 22 having (a) a nucleotide sequence of SEQ ID NO:5; or(b) a nucleotide sequence having at least 95% sequence identity with the nucleotide sequence of (a).
  • 26. An expression vector comprising the polynucleotide according to claim 25.
  • 27. A host cell transformed with the expression vector of claim 25.