Detecting, identifying, and phenotyping pathogens found in healthcare settings is critical both for diagnostic and surveillance purposes. Traditional bacterial and fungal diagnostic procedures rely on culture techniques that produce a genus or species level identification after 24-48 hours. Such tests are ordered for patients demonstrating symptoms indicative of an infection. While culture has been the standard diagnostic method for over one hundred years, its slow turnaround time means that a physician must prescribe antibiotics before knowing the identity of the organism or its drug resistances.
More recently, rapid techniques such as qPCR and mass spectrometry have allowed sub-24 hour turnaround times and enabled surveillance applications. For example, many hospitals in the United States test every patient for MRSA on admission to determine an appropriate caution level (e.g., quarantine) for patients who are at a high risk for spreading an infection to other patients. qPCR offers quick results but minimal information—a typical test only detects the presence of one or a few sequences from one organism. Testing for additional organisms or the presence of drug resistance or virulence genes adds substantially to the cost of the test.
A test that offers sub-24 hour turnaround time while identifying a large number of organisms would offer many benefits in a healthcare setting including broad-range surveillance and faster prescriptions of the most appropriate antibiotic. The present application discloses compositions, kits, and methods that can be used to detect any or several of a large set of organisms present in a sample as well as a number of families of drug resistance genes.
Provided herein are compositions, kits, and methods for identifying an organism. The organism can be a microbe, microorganism, or pathogen, such as a virus, bacterium, or fungus. In one embodiment, an organism is distinguished from another organism. In another embodiment, a strain, variant or subtype of the organism is distinguished from another strain, variant, or subtype of the same organism. For example, a strain, variant or subtype of a virus can be distinguished from another strain, variant or subtype of the same virus.
In some aspects, a probe set for identifying pathogenic organisms or strains in a sample comprising a plurality of probes that, when implemented in an assay, allows for detecting and distinguishing at least 5 different strains, variants, or subtypes of at least 3 pathogenic organisms, wherein each probe in said plurality comprises a first sequence that hybridizes to a 5′ end of a target sequence of said pathogen, a 3′ end of said pathogen, or to said target sequence is provided.
In some embodiments, pathogen strains or organisms comprise a virus, bacterium, or fungus. In some embodiments, the at least 3 pathogenic organisms include Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Acinetobacter baumanii, Clostridium difficile, Escherichia coli, Enterobacter (aerogenes, cloacae, asburiae), Enterococcus (faecium, faecalis), Klebsiella pneumoniae, Proteus mirabilis, Candida albicans, and Pseudomonas aeruginosa; or subtypes or strains thereof.
In some embodiments, the probe set can not only detect and distinguish between the at least 3 organisms but can also distinguish between common strains or subtypes of the organisms. In some embodiments, the probe set detects and distinguishes among the organisms responsible for more than 90% of the hospital acquired infections at some site.
In one aspect, a probe set for identifying the presence of drug resistance genes in the organisms in a sample comprising a plurality of probes that, when implemented in an assay, allows for detecting and distinguishing at least 3 classes of resistance genes, wherein each probe in said plurality comprises a first sequence that hybridizes to a 5′ end of a target sequence of said pathogen, a 3′ end of said pathogen, or to said target sequence is provided.
In one aspect, a kit containing any probe set described herein and the reagents and protocol to capture the target sequences of the organisms present in the input sample is provided.
In some aspects, a kit for the simultaneous detection of pathogens including three or more of the organisms listed in Table 2 is provided. In some embodiments, the kit is for research use. In some embodiments, the kit is a diagnostic kit. In some aspects, a kit for the simultaneous detection of antibiotic resistance genes including three or more of the genes listed in Table 3 is provided. In some embodiments, the kits described herein can be used to prepare DNA for massively parallel sequencing. In some embodiments, the kits described herein can provide molecular barcodes for the labeling of individual samples. In some embodiments, the kits described herein can include at least 10 of the probe sequences listed in Table 1.
In some embodiments, the kits described herein can be used to circularize single-stranded DNA probes by: (i) hybridization to a complementary target DNA sequence, (ii) extension across a gap by DNA polymerase, and (iii) ligation of the extended probe to form a single stranded, covalently closed circular DNA molecule.
In one aspect, a composition comprises a probe set for identifying pathogenic organisms or strains in a sample comprising a plurality of probes that, when implemented in an assay, allows for detecting and distinguishing three or more of the organisms listed in Table 2, wherein each probe in said plurality comprises a first sequence that hybridizes to a 5′ end of a target sequence of said pathogen, a 3′ end of said pathogen, or to said target sequence. In one embodiment, the plurality of probes, when implemented into an assay, allows for the substantially simultaneous detection and distinguishing of three or more of the antibiotic resistance genes listed in Table 3 is provided.
In one aspect, a composition comprises a probe set for identifying antibiotic resistance genes of pathogenic organisms or strains in a sample comprising a plurality of probes that, when implemented in an assay, allows for detecting and distinguishing three or more of the antibiotic resistance genes listed in Table 3, wherein each probe in said plurality comprises a first sequence that hybridizes to a 5′ end of a target sequence of said pathogen, a 3′ end of said pathogen, or to said target sequence is provided.
In one aspect, a composition comprises a probe set for identifying pathogenic organisms or strains in a sample comprising a plurality of probes that, when implemented in an assay, allows for detecting and distinguishing three or more organisms that cause Hospital Associated Infections (HAIs) at some site, wherein each probe in said plurality comprises a first sequence that hybridizes to a 5′ end of a target sequence of said pathogen, a 3′ end of said pathogen, or to said target sequence is provided. In some embodiments, the three or more organisms that cause HAIs at some site comprise organisms responsible for more than 90% of the hospital acquired infections at some site. In some embodiments, the three or more organisms that cause HAIs at some site comprise organisms responsible for more than 60% of the hospital acquired infections at some site. In some embodiments, the three or more organisms that cause HAIs at some site comprise organisms responsible for more than 30% of the hospital acquired infections at some site. In some embodiments, the site is a surgical site, catheter, ventilator, intravenous needle, respiratory tract catheter, medical device, blood, blood culture, urine, stool, fomite, wound, sputum, pure bacterial culture, mixed bacterial culture, bacterial colony, or any combination thereof.
In some embodiments, a probe set is operable to detect CARB, CMY, CTX-M, GES, IMP, KPC, NDM, ampC, OXA, PER, SHV, VEB, VIM, ermA, vanA, canB, mecA, or mexA family or classes of genes, or any combination thereof. In some embodiments, some of the genomic regions chosen as target sequences are known to be highly conserved such that each genus or species tends to contain a single version of the region, thus allowing genus or species identification. In some embodiments, some of the genomic regions chosen as target sequences are known to be highly variable such that each strain or substrain will contain a different version of the region, thus enabling strain or substrain identification and differentiation. In some embodiments, some portion of a plurality of the selected target sequences are sequenced simultaneously and then mapped to a database of reference sequences to determine the most likely identities of the organisms or genes present in the sample. In some embodiments, some portion of a plurality of the selected target sequences are sequenced simultaneously and then assembled into one or more consensus sequences. When sequencing information is gathered from the probes for antibiotic resistance genes, for plasmids, and for an organism, a distinguishing fingerprint can be derived for the pathogen, and can serve as means to identify the source and extent of an outbreak.
In one aspect, a kit comprising one or more reagents, wherein the reagents comprise a probe set according to claims 1-11, reagents for obtaining a sample, reagents for extracting nucleotides from a sample, enzymes, reagents for amplifying a region of interest, reagents for purifying nucleotides, reagents for purifying captured regions of interest, buffers, sequencing reagents, or any combination thereof, wherein the reagents allow for the capture of target sequences of three more pathogens listed in Table 2 is provided.
In one aspect, a kit comprising one or more reagents, wherein the reagents comprise a probe set according to claims 1-11, reagents for obtaining a sample, reagents for extracting nucleotides from a sample, enzymes, reagents for amplifying a region of interest, reagents for purifying nucleotides, reagents for purifying captured regions of interest, buffers, sequencing reagents, or any combination thereof, wherein the reagents allow for the capture of target sequences of three or more antibiotic resistance genes listed in Table 3 is provided.
In one aspect, a kit comprising one or more reagents, wherein the reagents comprise a probe set according to claims 1-11, reagents for obtaining a sample, reagents for extracting nucleotides from a sample, enzymes, reagents for amplifying a region of interest, reagents for purifying nucleotides, reagents for purifying captured regions of interest, buffers, sequencing reagents, protocol or any combination thereof, wherein the reagents allow for the capture of target sequences of three or more pathogens listed in Table 2 and capture of target sequences of three or more antibiotic resistance genes listed in Table 3 is provided.
In some embodiments, the reagents allow the capture reaction to be performed in a single tube. In some embodiments, the reagents allow the capture reaction to be performed in less than three hours. In some embodiments, the reagents allow the capture reaction to be performed in less than two hours. In some embodiments, the detection of the three or more pathogens occurs substantially simultaneously.
In some embodiments, the plurality of probes comprises at least 3 of the probe sequences listed in Table 1. In some embodiments, each probe comprises the first sequence that hybridizes to a 5′ end of said target sequence and a second sequence that hybridizes to a 3′ end of said target sequence. In some embodiments, the probe set can distinguish between strains or subtypes of the organisms. In some embodiments, the detection the three or more antibiotic resistance genes occurs substantially simultaneously. In some embodiments, the detection of the three or more pathogens and the three or more antibiotic resistance genes occurs substantially simultaneously.
In some embodiments, a kit allows for preparation of DNA for massively parallel sequencing. In some embodiments, a kit further comprises molecular barcodes for the labeling of individual samples.
In some embodiments, the probe set of a kit comprises at least 10 of the probe sequences listed in Table 1. In some embodiments, the probe set of a kit comprises at least 20 of the probe sequences listed in Table 1.
In some embodiments, kit reagents can be used to circularize single-stranded DNA probes by: (i) hybridization to a complementary target DNA sequence, (ii) extension across a gap by a DNA polymerase, and (iii) ligation of the extended probe to form a single stranded, covalently closed circular DNA molecule.
In one aspect, a method of identifying an organism or pathogenic strain, variant or subtype comprising: a) contacting a sample with a plurality of probes listed in Table 1, wherein said plurality of probes detects and distinguishes at least 3 different organisms or pathogenic strains listed in Table 2, or variants or subtypes thereof; b) hybridizing a 5′ end of a target sequence of said organisms or pathogenic strains, or variants or subtypes thereof, a 3′ end of said target sequence, or said target sequence with a probe of said plurality; c) sequencing said target sequence; and d) identifying from said sequencing said organisms or pathogenic strains, or variants or subtypes thereof is provided.
In one embodiment, the method is performed in less than 12 hours. In one embodiment, the identifying is performed in less than 3 hours. In one embodiment, the identifying is performed in less than 2 hours. In one embodiment, the identifying is with at least 99% specificity or sensitivity.
In one aspect, a method of stratifying a host into a therapeutic group comprising: a) contacting a sample from said host with a plurality of probes listed in Table 1, wherein each probe specifically distinguishes different non-host organisms or pathogenic strains listed in Table 2, or variants or subtypes thereof; b) hybridizing a 5′ end of a target sequence of a non-host organism or pathogen, a 3′ end of said target sequence, or said target sequence with a probe of said plurality; c) sequencing said target sequence; d) determining an identity of said non-host organism or pathogenic strain, or variant or subtype thereof, from said sequencing; and e) stratifying said host into a therapeutic group based on said identity is provided. In one embodiment, the method further comprises determining the genotype of the host from the sample.
In some embodiments, an additional non-host organism is identified. In some embodiments, an additional strain, variant or subtype of said organism or pathogen is identified. In some embodiments, the therapeutic group differs than a therapeutic group in which only one of the non-host organisms is identified. In some embodiments, the therapeutic group differs than a therapeutic group in which only one of said strains, variants, or subtypes of said pathogen is identified.
All publications, patents, and patent applications mentioned in this specification 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.
The novel features of the invention are set forth with particularity in the appended claims. A better understanding of the features and advantages of the present invention will be obtained by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings of which:
Approximately one out of every twenty hospitalized patients will contract a nosocomial infection, more commonly known as a hospital-acquired infection (HAI). More than 70 percent of the bacteria that cause HAIs can be resistant to at least one of the antibiotics most commonly used to treat them. Early detection can be important for controlling the spread of hospital-acquired infections. After culturing for growth and isolation of pathogens, clinical microbiology laboratories may rely on observable phenotype and simple biochemical assays to determine the bacterial type and antibiotic sensitivity. Determining the most effective antibiotic treatment for the infected patient, not the causal agent of the infection, is usually the prerogative of the physician. The resolution of conventional microbiological assays may be insufficient to determine the precise genotype underlying antibiotic resistance. Consequently, the same organism can infect multiple patients, and the spread of infection can go unnoticed for long periods.
Urinary tract infection (UTI) is the most common hospital-acquired infection. UTIs account for about 40 percent of hospital-acquired infections, and an estimated 80 percent of UTIs are associated with urinary catheters. Pneumonia is the second most common HAI. In critically ill patients, ventilator-associated pneumonia (VAP) is the most common nosocomial infection. VAP can double the risk of death, significantly increase intensive care unit (ICU) length of stay, and can add to each affected patient's hospital costs.
A key problem for microbiology labs is the turnaround time from receiving a microbial sample to determining key actionable information for patient care, such as antibiotic drug resistance within the sample, or strain identification for comparison to known high-risk strains. Existing technologies such as PCR or mass spectroscopy have allowed the turnaround time to be improved relative to classical methods for some actionable information, such as species identification, or presence of a select few drug resistance genes, but there are few practical approaches to assaying the large number of drug resistance genes or key species needed to be identified to confidently predict patient treatment.
DNA microarray offers broad detection ability for genomic loci, but is complicated by slow sample preparation and false positive and false negative sample results due to the hybridization based approach. Targeted DNA sequencing using the BioDetection kit allows the greater breadth of target detection, and higher resolution and higher accuracy discrimination due to the single base accuracy of DNA sequencing.
A second competing approach to targeted sequencing is whole genome sequencing. This approach has several disadvantages relative to the targeted sequencing approach provided by the invention. First, whole genome libraries contain many uninformative regions that are identical between the majority of isolates in a species, and thus provide no information to discriminate. These worthless reads mean that many more WGS reads are required per sample to capture informative regions, and prevent higher numbers of samples to be multiplexed into a single sequencing channel to amortize sequencing costs. Second, WGS libraries contain a representative fraction of any DNA present within a sample. As such, primary samples containing human tissue, or many uninteresting bacteria from the perspective of patient health, will comprise mainly of unwanted human or commensal bacterial reads. Efficient detection of important bacteria and drug resistance genes within a sample requires a more efficient targeted approach. Thirdly, library preparation times are slower and more laborious using WGS approaches, and the data analysis time significantly longer than that of a targeted sequencing approach in which only key informative regions are analyzed. This faster analysis reduces turnaround time and costs, and allow simplified data representations for easier understanding for clinical scientists unfamiliar with next generation sequencing data.
Provided herein are compositions, methods, systems and kits for detecting an organism, such as a pathogen, such as a pathogen that causes HAIs, as well as methods for using the system to identifying and detect the organism. The system can comprise a probe or plurality of probes. Also provided herein, are compositions, methods, systems and kits for detecting an organism, such as a pathogen, such as a pathogen that causes HAIs, and detecting and identifying antibiotic resistance genes, which, in some embodiments, can be performed simultaneously.
In some embodiments, the invention provides panels of probes and methods of using them, where the panels include circularizing capture probes, such as molecular inversion probes. Basic design principles for circularizing probes, such as simple molecular inversion probes (MIPs) as well as related capture probes are known in the art and described in, for example: Nilsson et al., Science, 265:2085-88 (1994); Hardenbol et al., Genome Res.; 15:269-75 (2005); Akharas et al., PLOS One, 9:e915 (2007); Porecca et al., Nature Methods, 4:931-36 (2007); Deng et al., Nat. Biotechnol., 27(4):353-60 (2009); U.S. Pat. Nos. 7,700,323 and 6,858,412; and International Publications WO 2011/156795, WO/1999/049079 and WO/1995/022623, all of which are incorporated by reference in their entirety.
A system for detection of an organism, such as identifying a strain, variant or subtype of a pathogen, can comprise a mixture or probe set comprising a plurality of probes. The target organism for a particular probe may be any organism, such as a viral, bacterial, fungal, archaeal, or eukaryotic, organisms, including single cellular and multicellular eukaryotes. In particular embodiments, a target organism is a pathogen. In some embodiments, target organisms include organisms associated with or that cause HAIs, such as those organisms provided in Table 2.
In some embodiments, each single-stranded capture probe can hybridize to two complementary regions on a target DNA with a gap region in between. An enzyme, such as DNA polymerase, can be used to fill in the gap using the target as template, and stop adding nucleotides when it reaches the phosphorylated 5′-terminus of the hybridized probe. An enzyme, such as a thermostable ligase, can be used to covalently close the extended probe to form a circular molecule. Exonucleases can be used to digest away residual probe molecules. The filled-in, circularized probe can be resistant to exonuclease digestion, and can serve as template for preparation of the sequencing library by known methods, such as PCR. Sample-associated barcodes can be added and can enable multiple barcoded samples to be blended and analyzed together, such as on a DNA sequencer.
A probe can refer to a sequence that hybridizes to another sequence. The probe can be a linear, unbranched polynucleic acid. The probe can comprise two homologous probe sequences separated by a backbone sequence, where the first homologous probe sequence is at a first terminus of the nucleic acid and the second homologous probe sequence is at the second terminus to the nucleic acid, and where the probe is capable of circularizing capture of a region of interest of at least 2 nucleotides. Circularizing capture can refer to a probe becoming circularized by incorporating the sequence complementary to a region of interest.
In a preferred embodiment, the probes contain two arms, joined by a backbone, that hybridize to a target sequence. A polymerase molecule can extend the 3′ end of the probe by copying a target region into a probe molecule. A ligase molecule can circularize a probe molecule by joining the 3′ end of the copied target to the 5′ end of the original probe molecule.
In one embodiment, probe arms can hybridize to the target nucleic acid molecule, surrounding the capture region; a polymerase extension can fill in the gap between the arms and a ligase can create a circular molecule out of the extended probe. After an exonuclease digestion removes the original template molecules, primers can be used to amplify the captured probes. The primers can contain a 3′ end homologous to the backbone (forward) and its reverse complement (reverse primer). The 5′ of the primer may contain a sequencing adapter for a particular next generation sequencing platform and may also contain a barcode sequence between the 5′ and 3′ segments such that multiple samples, each amplified with primers containing a sample-specific barcode, can be multiplexed into a single sequencing run. As the two probe arms are linked by a backbone, on-target binding is energetically favorable, even when many (hundreds, thousands, or tens of thousands) of probes are present in a single reaction (compare to PCR, in which one primer of a pair may hybridize and extend at an off-target locus). As with PCR, each MIP can capture a well-defined region of the target sequence (compare to hybridization capture methods, which yield a variety of molecules centered around the target).
In a preferred embodiment, a backbone of a probe molecule contains the same sequence in all probes. A backbone can contain two primer binding sites that allow amplification of probe arms and a captured target sequence. In a preferred embodiment, the primers used may contain a barcode to allow multiple samples to be separated after simultaneous sequencing. In a preferred embodiment, the primers also contain 5′ ends that adapters for a next-generation sequencing platform such as the Ion Torrent PGM, Illumina MiSeq, Illumina HiSeq, Nanopore, etc (
The probe set can include large number of probes, e.g., 10, 20, 30, 40, 50, 100, 200, 400, 500, 1000, 2000, 3000, 4000, 5000, 10000, 20000, 40000, 80000, or more. The probe set can include one or more probes directed to a large number of different target organisms, e.g., at least 10, 20, 40, 60, 80, 100, 150, 200, 250, 300, 400, 500, 600, 700, 800, 900, 1250, 1500, 1750, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, or more different target organisms. In some embodiments, a mixture including one or more probes to a plurality of target organisms contains only one probe to a target organism. In other embodiments, the mixture contains more than one probe to a target organism, e.g., about 2, 3, 4, 5, 6, 7, 8, 9, or 10 probes for a target organism. In certain embodiments, such as embodiments designed for use with patient test samples, the mixture further includes probes with homologous probe sequences that specifically hybridize to the host genome for applications such as host genotyping. In some embodiments, the mixtures of the invention further comprise sample internal calibration standards.
In one embodiment, the plurality of probes can detect at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 1750, or 2000 different organisms or pathogens. In another embodiment, the plurality of probes can detect at least 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1250, 1500, 1750, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, or more different strains, variants or sub-types of a pathogen or different strains or sub-types of different pathogens. In one embodiment, the probe set identifies detects at least 2 different bacterial or fungal strains. In another embodiment, the probe set identifies at least 50 different organisms, such as 50 different pathogens, or 50 different strains or subtypes of a pathogen, such as Staphylococcus aureus.
In another embodiment, the probe set can comprise probes capable of detecting a single molecule of a pathogen, thereby detecting, distinguishing or identifying the pathogen.
Each probe in the probe set can comprise the same or different backbone size, sequence, chemistries, configuration of barcodes and sequences, specific sequences for probe enrichment, target sites for probe cleavage, hybridization arm physical and chemical properties, probe identification regions, low structure optimized design, or any combination thereof. A probe may be selected to screen key loci for pathogenicity and/or drug susceptibility, and a genetic fingerprint or genotype for each sub-strain that contains key phenotypic information is generated.
In another embodiment, the probe comprises a first sequence that hybridizes to a 5′ end of a target sequence and a second sequence that hybridizes to a 3′ end of a target sequence, wherein the target sequence can be used to identify, detect, or distinguish an organism, such as pathogen. In some embodiments, the probes in the mixture each comprise a first and second homologous probe sequence—separated by a backbone sequence—that specifically hybridize to a first and second sequence (such as sequences 3′ and/or 5′ to a target sequence, respectively) in the genome of at least one target organism. In some embodiments the first and second homologous probe sequences are not complementary to the target sequence, but ligate to the 5′ and 3′ termini of a target nucleic acid, e.g. a microRNA, and possess appropriate chemical groups for compatibility with a nucleic acid-ligating enzyme, such as phosphorylated or adenylated 5′ termini, and free 3′ hydroxyl groups. The probe can be capable of circularizing capture of a region of interest.
In some embodiments, the homologous probe sequences or the sequences of the probe that hybridize or are homologous to the 3′ and/or 5′ region of a target sequence specifically hybridizes to target sequences in the genome of their respective target organism, but do not specifically hybridize to any sequence in the genome of a predetermined set of sequenced organisms—the exclusion set. In embodiments related to probes that do not hybridize directly to the capture target, the ‘homologous probe sequences’ are designed specifically to not substantially hybridize to any sequence within a defined set of genomes, i.e., an exclusion set. In the case of biological samples from a subject, the exclusion set includes the host's genome. In particular embodiments, the exclusion set also includes a plurality of viral, eukaryotic, prokaryotic, and archaeal genomes. In more particular embodiments, the plurality of viral, eukaryotic, prokaryotic, and archaeal genomes in the exclusion set may comprise sequenced genomes from commensal, non-virulent, or nonpathogenic organisms. In still more particular embodiments, the exclusion set for all probes in a mixture share a common subset of sequenced genomes comprising, for example, a host genome and commensal, non-virulent, or non-pathogenic organisms. In general, the exclusion set varies between probes in the mixture so that each probe in the mixture does not specifically hybridize with the target sequence of any other probe in the mixture.
In some embodiments, the sequences 3′ and/or 5′ to a target sequence are separated by a region of interest (e.g., the target sequence) of at least two nucleotides. In particular embodiments, they are separated by at least 5, 6, 7, 8, 9, 10, 12, 14, 18, 20, 25, 30, 50, 75, 100, 150, 200, 300, 400, 600, 1200, 1500, 2500, or more nucleotides. In some embodiments, the first and second target sequences are separated by no more than 5, 6, 7, 8, 9, 10, 12, 14, 18, 20, 25, 30, 50, 75, 100, 150, 200, 300, 400, 600, 1200, 1500, or 2500 nucleotides.
In some embodiments, probes can be designed to capture conserved regions, and upon DNA sequencing, can reveal polymorphisms and genetic aberrations that allow for the resolution of known or novel variants or closely related strains of organisms. In some embodiments two or more probes can be used for one or more or every organism wished to be tested for, which can permit discrimination of closely related organisms, even when a sample comprises more than one organism.
In one aspect, the probes in the probe set each comprising homologous probe sequences which are substantially free of secondary structure, do not contain long strings of a single nucleotide (e.g., they have fewer than 7, 6, 5, 4, 3, or 2 consecutive identical bases), are at least about 8 bases (e.g., 8, 10, 12, 14, 16, 18, 20, 22, 24, 25, 26, 27, 28, 30, or 32 bases in length), and have a Tm in the range of 50-72° C. (e.g., about 53, 54, 55, 56, 57, 58, 59, 60, 61, or 62° C.). In some embodiments the first and second homologous probe sequences are about the same length and have the same Tm. In other embodiments, length and Tm of the first and second homologous probe sequences differ. The homologous probe sequences in each probe may also be selected to occur below a certain threshold number of times in the target organism's genome (e.g., fewer than 20, 10, 5, 4, 3, or 2 times).
The backbone sequence of the probes may include a detectable moiety and a primer-binding sequence. In some embodiments, the backbone sequence of the probes comprises a second primer. In particular embodiments, the detectable moiety is a barcode. In certain embodiments the backbone further comprises a cleavage site, such as a restriction endonuclease recognition sequence. In certain embodiments, the backbone contains non-WatsonCrick nucleotides, including, for example, abasic furan moieties, and the like.
In another aspect, the invention provides a kit comprising one or more sets of probes, such as one or more sets of probes from the probes provided in Table 1. In one embodiment, a kit comprises one or more reagents for obtaining a sample (e.g., swabs), reagents for extracting DNA, enzymes (such as polymerase and/or ligase to capture a region of interest), reagents for amplifying the region of interest, reagents for purifying the DNA or amplified or captured regions of interest (e.g., purification cartridge), buffers, sequencing reagents, or any combination thereof. In one embodiment, the kit may be a low throughput kit, such as a kit for a small number of samples. For example, a kit may be a low throughput kit, such as a kit for 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 18, 20, 24, 28, 32, 36, 40, 42, 48, or between 8-48 samples. In another embodiment, the kit may be a high-throughput kit, such as a kit for a large number of samples. For example, a kit may be a high-throughput kit, such as a kit for 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 1750, 2000, or more samples. For example, a kit may be a high-throughput kit, such as a kit for between 50-96, 50-384, 50-1536, 96-384, 96-1536, or 384-1536 samples. In some embodiments, a kit as described herein can comprise enough reagents to prepare one or more specimens for sequencing. For example, a kit as described herein can comprise enough reagents to prepare 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 48, 50, 60, 70, 80, 90, 96, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 384, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 1536, 1750, 2000 or more specimens for sequencing.
Also provided herein is a method of using one or more probes disclosed herein, such as one or more probe set, for detecting, identifying, or distinguishing one or more organisms. The method can comprise identifying a an organism with a plurality of probes can detect at least 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 1750, or 2000 different pathogens. In another embodiment, the plurality of probes can detect at least 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1250, 1500, 1750, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, or more different strains, variants or sub-types of a pathogen or different strains or sub-types of different pathogens.
The method can comprise detecting or distinguishing different organisms, different pathogens, different strains, variants or sub-types of a pathogen or different strains, variants or sub-types of different pathogens, with at least 70% sensitivity, specificity, or both, such as with at least 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, or 89% sensitivity, specificity, or both, such as with at least 90% sensitivity, specificity, or both. Each probe may detect or distinguish different organisms, different pathogens, different strains or sub-types of a pathogen or different strains or sub-types of different pathogens with at least 91, 92, 93, 94, 95, 96, 97, 98, 99 or 100% sensitivity, specificity, or both, in an assay. Alternatively, a combination of probes may be used for detecting or distinguishing different organisms, different pathogens, different strains, variants or sub-types of a pathogen or different strains, variants or sub-types of different pathogens, with at least 70% sensitivity, specificity, or both, such as with at least 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, or 89% sensitivity, specificity, or both, such as with at least 90% sensitivity, specificity, or both. Furthermore, the confidence level for determining the specificity, sensitivity, or both, may be with at least 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% confidence.
In one embodiment, a method for detecting the presence of one or more target organisms is by contacting a sample suspected of containing at least one target organism with any of the probe set disclosed herein, capturing a region of interest of the at least one target organism (e.g., by polymerization and/or ligation) to form a circularized probe, and detecting the captured region of interest, thereby detecting the presence of the one or more target organisms.
In certain embodiments, the captured region of interest may be amplified to form a plurality of amplicons (e.g., by PCR). In some embodiments the sample is treated with nucleases to remove the linear nucleic acids after probe-circularizing capture of the region of interest. In some embodiments, the circularized probe is linearized, e.g., by nuclease treatment. In other embodiments the circularized probe molecule is sequenced directly by any means known in the art, without amplification. In certain embodiments, the circularized probe is contacted by an oligonucleotide that primes polymerase-mediated extension of the molecules to generate sequences complementary to that of the circularized probe, including from at least one to as many as 1 million or more concatemerized copies of the original circular probe.
In particular embodiments, the circularized probe molecule is enriched from the reaction solution by means of a secondary-capture oligonucleotide capture probe. A secondary-capture oligonucleotide capture probe may comprise a moiety designed to be captured, such as a biotin molecule, and a nucleic acid sequence designed to hybridize to at least 6 nucleotides of the circularized probe. The nucleic acid sequence designed to hybridize to at least 6 nucleotides of the circularized probe may include 1, 2, 4, 8, 16, 32 or more nucleotides of the polymerase-extended capture product.
In certain embodiments, the probe and/or captured region of interest is sequenced by any means known in the art, such as polymerase-dependent sequencing (including, dideoxy sequencing, pyrosequencing, and sequencing by synthesis) or ligase based sequencing (e.g., polony sequencing). The sequencing can be by Sanger sequencing or massive parallel sequencing, such as “next generation” (Next-gen) sequencing, second generation sequencing, or third generation sequencing. For example, sequencing can be by second generation or third generation sequencing methods, such as using commercial platforms such as Illumina, 454 (Roche), Solid, Ion Torrent PGM (Life Technologies), PacBio, Oxford, Life Technologies QDot, Nanopore, or any other available sequencing platform. Massive parallel sequencing can allow for the simultaneous sequencing of one million to several hundred millions, for example 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 48, 50, 60, 70, 80, 90, 96, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, or 900 million, of reads from amplified DNA clones. The reads can read any number of bases, such as 50-400 bases.
An internal nucleotide control, such as DNA at a known concentration, can be used with the methods and samples described herein. In one embodiment, an internal nucleotide control can serve as an internal calibrator, such as for determining copy number. In some embodiments, a sequencing read that aligns to the calibrator can also serve as a positive control for the performance of the assay, such as in the context of every sample.
In one aspect, the probes, methods, and kits described herein can be used to test for the presence of one or more organisms, such as those in Table 2. In one embodiment, the probes, methods, and kits described herein can be used to test for the presence of one or more antibiotic resistance genes, such as those in Table 3. In a preferred embodiment, the probes, methods, and kits described herein can be used to test for the presence of one or more organisms, such as those in Table 2, and test for the presence of one or more antibiotic resistance genes, such as those in Table 3, in parallel, such as in one sample tube, in the same sample, simultaneously, or any combination thereof. In some embodiments, in a single reaction tube, a kit can be used to test for the two or more microbes most commonly associated with hospital-acquired infections, and simultaneously tests for the presence of two or more antibiotic resistance genes. For example, a kit can be used to test for the 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or more microbes most commonly associated with hospital-acquired infections, and simultaneously tests for the presence of 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, or more antibiotic resistance genes simultaneously. For example, in a single reaction tube, a kit can be used to test for the 12 microbes most commonly associated with hospital-acquired infections, and simultaneously tests for the presence of 18 antibiotic resistance genes.
In one embodiment, one or more organisms can be identified from a sample, such as a sample form a host and the organism being identified is a pathogen. In one embodiment, the sample is a biological sample, such as from a mammal, such as a human. In another embodiment, a genotype of the host is identified or detected from the sample or another sample from the host. The identification of one or more organisms (such as one or more pathogens, such as different pathogens or subtypes or strains of pathogens), can be used to select one or more therapeutics or treatments for the host. In another embodiment, the identification of one or more organisms (such as one or more pathogens, such as different pathogens or subtypes or strains of pathogens), can be used to stratify the host into a therapeutic group, such as for a particular drug treatment or clinical trial. In one embodiment, HPV strain identification can be used to stratify a host into a cancer therapeutic group or to select a cancer treatment.
The yet another embodiment identification of one or more organisms (such as one or more pathogens, such as different pathogens or subtypes or strains of pathogens) and the genotype of a host can be used to select one or more therapeutics or treatments for the host. In another embodiment, the identification of one or more organisms (such as one or more pathogens, such as different pathogens or subtypes or strains of pathogens) and the genotype of the host can be used to stratify the host into a therapeutic group, such as for a particular drug treatment or clinical trial.
Also provided herein is a method for identifying an organism, such as a genetic signature of an organism, a subtype or strain of a pathogen in a short timeframe or with a fast turnaround time. In another embodiment, a genotype of an individual or host can also be identified within the short time frame. For example, the identification of a pathogen in a sample or the genotype of a host can completed in less than 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours. In one embodiment, from contacting the sample with one or more probes to identifying the organism by sequencing can be performed in less than 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours. In yet another embodiment, from contacting the sample with the probe to identifying the organism (such as one or more pathogens) by sequencing, and transmitting the results to a health care professional (such as a clinician or physician) can be performed in less than 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours. In yet another embodiment, from contacting the sample with the probe to identifying the organism (such as one or more pathogens) by sequencing, transmitting the results to a health care professional (such as a clinician or physician), and selection of a therapeutic can be performed in less than 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 hours.
Also provided herein is a method for simultaneous quantification and identification of an organism, such as identifying one or more subtypes or substrains of a pathogen. Multiplexing is also provided herein, wherein a multiple pathogens, substrains or subtypes of pathogens, can be detected simultaneously or in a single reaction tube.
In one embodiment, conversion of sequence data to quantitative report can be performed by using selected validated parameters. Any software known in the arts can be used for any of the methods disclosed herein.
In some embodiments, an organism identified and/or quantified using the methods described herein can be the cause of an infection in a subject, such as a nosocomial infection (also known as a hospital-acquired infection (HAI)) which is an infection whose development is favored by a hospital environment. In some embodiments, an infection can be acquired by a patient during a hospital visit or one developing among hospital staff. Such infections can include, for example, fungal and bacterial infections and can be aggravated by a reduced resistance of individual patients. Organisms responsible for HAIs can survive for a long time on surfaces in the hospital and can enter or be transmitted to the body through wounds, catheters, and ventilators. In some embodiments, the route of transmission can be contact transmission (direct or indirect), droplet transmission, airborne transmission, common vehicle transmission, vector borne transmission, or any combination thereof.
People in hospitals can already be in a poor state of health, impairing their defense against bacteria. Advanced age or premature birth along with immunodeficiency, due to, for example, drugs, illness, or irradiation, present a general risk. Other diseases can present specific risks, for example, chronic obstructive pulmonary disease can increase chances of respiratory tract infection. Invasive devices, for example, intubation tubes, catheters, surgical drains, and tracheostomy tubes can bypass the body's natural lines of defense against pathogens and can provide an easy route for infection. Patients already colonized on admission can be put at greater risk when they undergo a procedure, such as an invasive procedure. A patient's treatment itself can leave the patient vulnerable to infection, for example, immunosuppression and antacid treatment can undermine the body's defenses, while antimicrobial and recurrent blood transfusions can also be risk factors.
Non-limiting examples of HAIs include Ventilator associated pneumonia (VAP), Staphylococcus aureus, Methicillin resistant Staphylococcus aureus (MRSA), Candida albicans, Pseudomonas aeruginosa, Acinetobacter baumannii, Stenotrophomonas maltophilia, Clostridium difficile, Tuberculosis, Urinary tract infection, Hospital-acquired pneumonia (HAP), Gastroenteritis, Vancomycin-resistant Enterococcus (VRE), and Legionnaires' disease. In some embodiments, HAIs can be caused by one or more of the organisms provided in Table 2.
Nucleotides, such as DNA and RNA, can be isolated from any suitable sample and detected using the probes described herein. Non-limiting examples of sample sources include catheters, medical devices, blood, blood cultures, urine, stool, fomites, wounds, sputum, pure bacterial cultures, mixed bacterial cultures, and bacterial colonies.
In some embodiments, the probe sets described herein can be used to detect and distinguish among the organisms responsible for more than 10% of the hospital acquired infections at a site. For example, the probe sets described herein can be used to detect and distinguish among the organisms responsible for more than 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100% of the hospital acquired infections at a site. In some embodiments, a site can be a surgical site, wound, tract, urinary catheter, ventilator, intravenous needle, syringe, respiratory tract, invasive device, intubation tube, catheter, surgical drain, tracheostomy tube, saline flush syringe, vial, bag, tube or any combination thereof.
A further aspect of the invention provides methods of making the mixtures of probes provided by the invention. The methods comprise providing a set of reference genomes and an exclusion set of genomes. The sequence of the reference genomes can be partitioned (in silico) into n-mer strings of about 18-50 nucleotides. The partitioned n-mer strings can be screened to eliminate redundant sequences, sequences with secondary structure, repetitive sequences (e.g., strings with more than 4 consecutive identical nucleotides), and sequences with a Tm outside of a predetermined range (e.g., outside of 50-72° C.). The screened n-mers can be further screened to identify homologous probe sequences by eliminating n-mers that specifically hybridize to a sequence in the genome in the exclusion set of genomes (e.g., if a pairwise alignment contains 19 of 20 matches in an n-mer, such as a 25-mer) or occurs in the genome of the target organism more than a specified number of times. The screening may also remove n-mers that are present in more than or less than a specified number of the reference genomes. The screening may also remove n-mers that will not interact favorably with enzymes to be used with the probe sequences. For example, a particular polymerase may work with higher efficiency if the last 3′ base of the probe is a G or C. Similarly, a particular ligase may work more efficiently on certain bases at the ligation junction. For example, Ampligase (Epicentre) will ligate a gap between AG and GT at least 10 times more efficiently than a gap between TC and CC.
In particular embodiments, a homologous probe sequence may occur only once in the genome of the target organism. For target organisms with a single-stranded genome, the homologous probe sequence may occur only once in the complement of the genome of the target organism. In one embodiment, where a sequenced variant of the target organism is available (e.g., the same species, genus, or serovar), the homologous probe sequences can be filtered so as to specifically hybridize to the genome of the additional sequenced variant(s) resulting in a probe that groups related organisms. In an alternate embodiment, the homologous probe sequences can be filtered so as to not specifically hybridize to the genome of the sequenced variant (e.g., the sequenced variant is part of the exclusion set), resulting in a probe that discriminates between related organisms. These filter processes can be iterated for each target organism to be detected by the particular mixture. In some embodiments, the candidate homologous probe sequences can be screened to eliminate those that will specifically hybridize with other probes in the mixture.
Probe selection can be based on a database of different pathogens, strains of a pathogen, or both, such as a database comprising more than 10 different pathogens, strains of a pathogen, or both. For example, probe selection can be based a database comprising more than 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 1750, 2000, or more different pathogens, strains of a pathogen, or both. In some embodiments, probe selection can be based on a database of different pathogens, strains of a pathogen, or both, that are known to cause HAIs, such as a database comprising more than 10 different pathogens, strains of a pathogen, or both, that are known to cause HAIs. For example, probe selection can be based a database comprising more than 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1250, 1500, 1750, 2000, or more different pathogens, strains of a pathogen, or both, that are known to cause HAIs, and optionally with additional strains or sub-types of other pathogens. In one embodiment, probes for organisms associated with HAIs are selected by partitioning all available genomes of organisms associated with HAIs into one or more subsets based on sequence similarity. For each subset candidate probe sets are generated that capture all strains. A filter can then be applied for specificity against human/microbial/viral/fungal genomes.
Some of clinical tests based on the methods disclosed herein rely on the ability to determine or approximate the number of input template molecules (genomes) in a sample. A two step method can be used to calculate the number of template molecules in a sample from the sequencing read counts. 1) Each sample sequenced can have a known quantity of a control sequence added to it. One embodiment employs GFP as the control sequence. It is contemplated to use several control sequences added in different quantities. The first step in analyzing sequencing reads can be to normalize the counts based on the number of reads that came from the control sequence. This normalization accounts for the fact that more material from sample A than from sample B may have been put into the sequencing reaction. 2) Since different MIPs (or primer pairs or hybridization capture probes) might work with different efficiencies, the second step of the quantification process can be to normalize between probes. In one embodiment, this normalization relies on experiments in which fixed amounts of different templates were sequenced and might reveal, e.g., that a probe against one strain or organism produces 2 circularized MIPs per template but a probe against anther strain or organism produces 3. Thus, the count for the first probe might be multiplied by 33.3 and the count for the second probe divided by 50 to produce comparable load counts for the two strains.
Some embodiments use a mixed quantity of GFP as the control sequence and a variable quantity of one or more organisms or strains. Some samples may contain only GFP and template DNA while others also included a human background. After the sequencing reads are separated by sample, the method can calculate the ratio of reads, such as viral (HPV-18, HIV-CN006, and HIV-CN009) reads, to GFP and plots that ratio against the number of template molecules in the reaction. Those plots indicate generally excellent agreement between the viral/GFP ratio and the input template quantity.
Compared to other assays, high throughput sequencing offers a relatively unique ability to detect and genotype the pathogen DNA and the human DNA in a sample from a single reaction. In current clinical practice, genotyping the pathogen and human may require multiple tests, potentially doubling (or more) the expense compared to simply detecting a pathogen. The methods disclosed herein enable simultaneous genotyping with minimal added cost and often no added labor. Other selection/enrichment technologies would also enable these tests.
The methods disclosed herein provide for simultaneously detecting or genotyping multiple pathogens.
For example, the methods provide for: coinfection of HIV and HCV, simultaneously genotyping/quantifying HIV while testing for diseases common in immunocompromised patients. Doctors typically only test for diseases like Candida, CMV, etc upon presentation of some other symptom. However, if the tests can be added at minimal cost, this might be a unique market and feature for Pathogenica's product, for example, HPV and other STIs. There is an interest in testing for HPV and other STIs, primarily chlamydia and gonorrhea to simplify screening, especially in patient populations with limited access to doctors. There is also an interest in testing for these diseases as additional risk factors for cervical cancer.
Table 1 lists the probe arm sequences in one embodiment of the present invention designed to detect a variety pathogenic organisms, such as those provided in Table 2, from a sample. Non limiting examples include Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Acinetobacter baumanii, Clostridium difficile, Escherichia coli, Enterobacter (aerogenes, cloacae, asburiae), Enterococcus (faecium, faecalis), Klebsiella pneumoniae, Proteus mirabilis, Candida albicans, and Pseudomonas aeruginosa. The probe set can also be used to detect many common drug resistance genes, including, but not limited to CARB, CMY, CTX-M, GES, IMP, KPC, NDM, Other ampC, OXA, PER, SHV, VEB, VIM, ermA, vanA, vanB, mecA, and mexA,
Tables 1 and 3-14 provide regions of interest (leftmost columns, using the format of descriptor (e.g., organism or gene, if applicable)_reference accession number (if applicable)_first nucleotide of capture region_last nucleotide of capture region. For example, the probe “acinetobacter_NC—010611—627997—628164” is directed to acineobacter, and is predicted to be capable of capturing nucleotides corresponding to nucleotides 627997 to 628164 of the reference sequence NC—010611. Reference accession sequences can be obtained from, for example, the NCBI Entrez portal. Tables 3, 5, 7, 9, 11, and 13 provide the regions of interest and corresponding annotated genes within that region. Tables 4, 6, 8, 10, 12, and 14, in turn, provide particular exemplary oligonucleic acid sequences—provided as pairs that can be used in a MIP or adapted for use as conventional PCR primers—predicted to capture the region of interest listed in the first column of the. “Binding region 1” in Tables 4, 6, 8, 10, 12, and 14 correspond to the 5′, or ligation arm, of a MIP probe and “Binding region 2” corresponds to the 3′, or extension arm of a MIP probe. In some embodiments, substantially similar sequences to the regions of interest provided in Tables 1 and 3-14 can be used. In some embodiments, the substantially similar sequences wherein the substantially similar sequences are 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.5, or 100% identical to the sequence of the regions of interest. In other embodiments, the substantially similar sequences have endpoints within 100, 90, 80, 70, 60, 50, 40, 35, 30, 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0 nucleotides upstream or downstream of either of the endpoints of the regions of interest. In still other embodiments, the substantially similar sequences are 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.5, or 100% identical to the sequence of the regions of interest and have endpoints within 100, 90, 80, 70, 60, 50, 40, 35, 30, 25, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, or 0 nucleotides upstream or downstream of either of the endpoints of the regions of interest. In still more particular embodiments, the particular exemplified endpoints and binding regions are use, e.g., as pairs of binding regions in either a single MIP capture probe, or as pairs of conventional PCR primers, e.g., using the reverse complement of the ligation arm.
Subsets of the regions of interest or particular exemplary binding regions in tables Tables 1 and 3-14 can be used concordant with the present invention, e.g., 10, 20, 30, 40, 50, 60, 70, 80, 90, 95, 96, 97, 98, 99, or 100% of the regions of interest or binding regions in the tables, e.g.:
oligonucleic acid molecules capable of i) amplifying, geometrically by polymerase chain reaction or ii) circularizing capture of 1, 2, 3, 4, 5, 10, 15, 16, or all 17, of the regions of interest provided in column 1 of Table 3, or substantially similar sequences;
oligonucleic acid molecules capable of i) amplifying, geometrically by polymerase chain reaction or ii) circularizing capture of 1, 2, 3, 4, 5, 10, 15, 20, 30, 50, 100, or all 134, of the regions of interest provided in column 1 of Table 5, or substantially similar sequences, such as:
oligonucleic acid molecules capable of i) amplifying, geometrically by polymerase chain reaction or ii) circularizing capture of, 1, 2, 3, 4, 5, 10, or all 13, of the regions of interest provided in column 1 of Table 7, or substantially similar sequences;
oligonucleic acid molecules capable amplifying, geometrically by polymerase chain reaction, or circularizing capture of, 1, 2, 3, 4, 5, 10, 20, 40, 60, 80, or all 85, of the regions of interest provided in column 1 of Table 9, or substantially similar sequences;
oligonucleic acid molecules capable of i) amplifying, geometrically by polymerase chain reaction or ii) circularizing capture of, 1, 2, 3, 4, 5, 10, 20, 25, or all 29 of the regions of interest provided in column 1 of Table 11, or substantially similar sequences;
oligonucleic acid molecules capable of i) amplifying, geometrically by polymerase chain reaction or ii) circularizing capture of, 1, 2, 3, 4, 5, 10, 15, or all 20, of the regions of interest provided in column 1 of Table 13, or substantially similar sequences;
oligonucleic acid molecules comprising 1, 2, 4, 6, 8, 10, 15, 20, 25, 30, or all 34 of the sequences, or reverse complements thereof, provided in the second or third column of table 4;
oligonucleic acid molecules comprising 1, 2, 4, 6, 8, 10, 20, 50, 100, 150, 200, 250, or all 268 of the sequences, or reverse complements thereof, provided in the second or third column of table 6;
oligonucleic acid molecules comprising 1, 2, 4, 6, 8, 10, 15, 20, 25, or all 26 of the sequences, or reverse complements thereof, provided in the second or third column of table 8;
oligonucleic acid molecules comprising 1, 2, 4, 6, 8, 10, 20, 50, 100, 150, or all 170 of the sequences, or reverse complements thereof, provided in the second or third column of table 10;
oligonucleic acid molecules comprising 1, 2, 4, 6, 8, 10, 20, 30, 40, 50, or all 56 of the sequences, or reverse complements thereof, provided in the second or third column of table 12;
oligonucleic acid molecules comprising 1, 2, 4, 6, 8, 10, 20, 30, or all 40 of the sequences, or reverse complements thereof, provided in the second or third column of table 14, as well as any combinations of the foregoing.
Table 1 provides particular probes assembled as molecular inversion probes (MIPs) capable of circularizing capture of the indicated region of interest in the leftmost column. These exemplary probes share a common backbone sequence of GTTGGAGGCTCATCGTTCCTATATTCCACACCACTTATTATTACAGATGTTATGCT CGCAGGTC, except for the peGFP_N1—730—925 probe, which uses the backbone GTTGGAGGCTCATCGTTCCTATATTCCTGACTCCTCATTGATGATTACAGATGTTA TGCTCGCAGGTC. Alternative backbone sequences can readily be used. Conventional PCR primer pairs can be adapted from these MIP probes by omitting the intervening backbone sequence and providing the reverse complement of the ligation arm (5′) probe. Tables 4, 6, 8, 10, 12, and 14 provide subsets of the probes in Table 1 where the individual arms are provided in the second and third columns, respectively. Tables 4, 6, 8, 10, 12, and 14 collectively provide the same probe arms that are present in Table 1.
Acinetobacter baumannii 1656-2
Acinetobacter baumannii AB0057
Acinetobacter baumannii AB307-0294
Acinetobacter baumannii ACICU
Acinetobacter baumannii ATCC 17978
Acinetobacter baumannii AYE
Acinetobacter baumannii MDR-ZJ06
Acinetobacter baumannii SDF
Acinetobacter baumannii TCDC-AB0715
Acinetobacter calcoaceticus PHEA-2
Acinetobacter sp. ADP1
Acinetobacter sp. DR1
Clostridium acetobutylicum ATCC 824
Clostridium acetobutylicum DSM 1731
Clostridium acetobutylicum EA 2018
Clostridium beijerinckii NCIMB 8052
Clostridium botulinum A2 str. Kyoto
Clostridium botulinum A3 str. Loch Maree
Clostridium botulinum A str. ATCC 19397
Clostridium botulinum A str. ATCC 3502
Clostridium botulinum A str. Hall
Clostridium botulinum B1 str. Okra
Clostridium botulinum Ba4 str. 657
Clostridium botulinum BKT015925
Clostridium botulinum B str. Eklund 17B
Clostridium botulinum E3 str. Alaska E43
Clostridium botulinum F str. 230613
Clostridium botulinum F str. Langeland
Clostridium botulinum H04402 065
Clostridium cellulolyticum H10
Clostridium cellulovorans 743B
Clostridium clariflavum DSM 19732
Clostridium difficile 630
Clostridium difficile BI1
Clostridium difficile BI9
Clostridium difficile CD196
Clostridium difficile strain 2007855
Clostridium difficile strain CF5
Clostridium difficile strain M120
Clostridium difficile M68
Clostridium difficile R20291
Clostridium kluyveri DSM 555
Clostridium kluyveri NBRC 12016
Clostridium lentocellum DSM 5427
Clostridium ljungdahlii DSM 13528
Clostridium novyi NT
Clostridium perfringens ATCC 13124
Clostridium perfringens SM101
Clostridium perfringens str. 13
Clostridium phytofermentans ISDg
Clostridium saccharolyticum-like K10
Clostridium saccharolyticum WM1
Clostridium sp. SY8519
Clostridium sticklandii DSM 519
Clostridium tetani E88
Clostridium thermocellum ATCC 27405
Clostridium thermocellum DSM 1313
Enterobacter aerogenes KCTC 2190
Enterobacter asburiae LF7a
Enterobacter cloacae SCF1
Enterobacter cloacae subsp.cloacae ATCC 13047
Enterobacter cloacae subsp. cloacae NCTC 9394
Enterobacter sp. 638
Enterococcus faecalis 62
Enterococcus faecalis OG1RF
Enterococcus faecalis V583
Enterococcus sp. 7L76
Escherichia coli 042
Escherichia coli 536
Escherichia coli 55989
Escherichia coli ABU 83972
Escherichia coli APEC O1
Escherichia coli ATCC 8739
Escherichia coli BL21(DE3)
Escherichia coli ‘BL21-Gold(DE3)pLysS AG'
Escherichia coli B str. REL606
Escherichia coli BW2952
Escherichia coli CFT073
Escherichia coli DH1 (ME8569)
Escherichia coli E24377A
Escherichia coli ED1a
Escherichia coli ETEC H10407
Escherichia coli HS
Escherichia coli IAI1
Escherichia coli IAI39
Escherichia coli IHE3034
Escherichia coli KO11
Escherichia coli LF82
Escherichia coli NA114
Escherichia coli O103: H2 str. 12009
Escherichia coli O111:H-str. 11128
Escherichia coli O127:H6 str. E2348/69
Escherichia coli O157:H7 str. EC4115
Escherichia coli O157:H7 str. EDL933
Escherichia coli O157:H7 str. Sakai
Escherichia coli O157:H7 str. TW14359
Escherichia coli O26:H11 str. 11368
Escherichia coli O55:H7 str. CB9615
Escherichia coli O7:K1 str. CE10
Escherichia coli O83:H1 str. NRG 857C
Escherichia coli S88
Escherichia coli SE11
Escherichia coli SE15
Escherichia coli SMS-3-5
Escherichia coli str. ‘clone D i14’
Escherichia coli str. ‘clone D i2’
Escherichia coli str. K-12 substr. DH10B
Escherichia coli str. K-12 substr. MDS42
Escherichia coli str. K-12 substr. MG1655
Escherichia coli str. K12 substr. W3110
Escherichia coli UM146
Escherichia coli UMN026
Escherichia coli UMNK88
Escherichia coli UTI89
Escherichia coli W
Escherichia fergusonii ATCC 35469
Klebsiella pneumoniae 342
Klebsiella pneumoniae KCTC 2242
Klebsiella pneumoniae NTUH-K2044
Klebsiella pneumoniae subsp. pneumoniae MGH
Klebsiella variicola At-22
Proteus mirabilis HI4320
Pseudomonas aeruginosa LESB58
Pseudomonas aeruginosa M18
Pseudomonas aeruginosa NCGM2.S1
Pseudomonas aeruginosa PA7
Pseudomonas aeruginosa PAO1
Pseudomonas aeruginosa UCBPP-PA14
Pseudomonas brassicacearum subsp. brassicacearum
Pseudomonas entomophila L48
Pseudomonas fluorescens F113
Pseudomonas fluorescens Pf0-1
Pseudomonas fluorescens Pf-5
Pseudomonas fluorescens SBW25
Pseudomonas fulva 12-X
Pseudomonas mendocina NK-01
Pseudomonas mendocina ymp
Pseudomonas putida BIRD-1
Pseudomonas putida F1
Pseudomonas putida F1
Pseudomonas putida GB-1
Pseudomonas putida KT2440
Pseudomonas putida S16
Pseudomonas putida W619
Pseudomonas stutzeri A1501
Pseudomonas stutzeri ATCC 17588 = LMG 11199
Pseudomonas stutzeri DSM 4166
Pseudomonas syringae pv. phaseolicola 1448A
Pseudomonas syringae pv. syringae B728a
Pseudomonas syringae pv. tomato str. DC3000
Shigella boydii CDC 3083-94
Shigella boydii Sb227
Shigella dysenteriae Sd197
Shigella flexneri 2002017
Shigella flexneri 2a str. 2457T
Shigella flexneri 2a str. 301
Shigella flexneri 5 str. 8401
Shigella sonnei Ss046
Staphylococcus aureus
Staphylococcus carnosus subsp. carnosus
Staphylococcus epidermidis
Staphylococcus haemolyticus JCSC1435
Staphylococcus lugdunensis
Staphylococcus pseudintermedius
Staphylococcus saprophyticus subsp.
Staphylococcus aureus
Staphylococcus saprophyticus
Staphylococcus epidermis
Acinetobacter baumannii
Enterococcus faecalis
Enterobacter cloacae
Enterobacter aerogenes
Enterococcus faecium
Candida albicans
Klebsiella pneumoniae
Escherichia coli
Clostridium difficile
Proteus mirabilis
Pseudomonas aeruginosa
acinetobacter_NC_010
acinetobacter_NC_010
acinetobacter_CP0025
acinetobacter_NC_011
acinetobacter_NC_010
acinetobacter_NC_010
acinetobacter_NC_010
acinetobacter_NC_010
acinetobacter_NC_009
clostridium_NC_01397
clostridium_FN665653_
clostridium_NC_01397
clostridium_NC_01331
clostridium_FN668375_
clostridium_NC_01331
clostridium_FN665654_
clostridium_FN668941_
clostridium_NC_01397
clostridium_NC_00336
clostridium_NC_01331
clostridium_NC_00908
clostridium_NC_01331
clostridium_NC_01331
clostridium_FN668941_
clostridium_NC_01331
clostridium_FN665653_
clostridium_NC_00336
clostridium_FN665653_
clostridium_NC_00908
clostridium_NC_01331
clostridium_FN665652_
clostridium_NC_01331
clostridium_FN668375_
clostridium_FN668941_
clostridium_NC_01397
clostridium_NC_01331
clostridium_NC_00908
clostridium_FN665652_
clostridium_NC_01331
clostridium_NC_01331
clostridium_NC_01331
clostridium_FN665654_
clostridium_NC_01331
clostridium_NC_01331
clostridium_NC_01331
enterobacter_NC_0141
enterobacter_NC_0156
enterobacter_FP92904
enterobacter_NC_0094
enterococcus_FP92905
enterococcus_CP00262
enterococcus_FP92905
enterococcus_FP92905
enterococcus_NC_0046
klebsiella_NC_009648_
klebsiella_NC_009648_
klebsiella_NC_009648_
klebsiella_NC_009648
klebsiella_NC_012731_
klebsiella_NC_012731_
proteus_NC_010554_54
pseudomonas_NC_00846
pseudomonas_NC_00846
pseudomonas_NC_00965
pseudomonas_NC_00846
pseudomonas_NC_01032
pseudomonas_NC_00846
staph_FN433596_28440
staph_NC_009632_1198
staph_FN433596_25212
staph_NC_009487_4308
staph_NC_009782_2086
staph_NC_009782_5825
staph_NC_013450_9910
staph_NC_013450_1360
staph_AM990992_25260
staph_NC 010079_3612
staph_NC_007795_2085
staph_NC_009641_2312
staph_FN433596_21445
staph_NC_009782_5485
staph_AM990992_16566
staph_NC_007793_4422
staph_NC_009641_1102
staph_NC_009641_1137
staph_FN433596_27157
staph_NC_009782_6066
staph_FN433596_65762
pseudomonas_NC_00846
pseudomonas_NC_00251
pseudomonas_NC_00846
pseudomonas_NC_00965
pseudomonas_NC_00846
pseudomonas_NC_00251
pseudomonas_NC_00251
pseudomonas_NC_00846
pseudomonas_NC_00846
pseudomonas_AP012280_
pseudomonas_AP012280_
enterococcus_NZ_GG70
enterococcus_NZ_GG70
enterococcus_NZ_GL45
enterococcus_NZ_GG70
enterococcus_NZ_GG70
enterococcus_NZ_GL45
enterococcus_NZ_GG69
enterococcus_NC_0046
enterococcus_NZ_GG70
enterococcus_NZ_GL45
enterococcus_NZ_GG66
proteus_NZ_GG661998_
proteus_NC_010554_20
proteus_NZ_GG668576_
proteus_NZ_GG668594_
proteus_NZ_GG668579_
proteus_NC_010554_24
proteus_NC_010554_30
proteus_NC_010554_45
pseudomonas_NC_00908
pseudomonas_NC_00908
pseudomonas_NC_01661
pseudomonas_NC_01660
pseudomonas_NC_01660
pseudomonas_NC_01041
pseudomonas_NC_00596
pseudomonas_NC_00859
pseudomonas_NC_01651
pseudomonas_NC_00596
enterobacter_NC_0146
enterobacter_NZ_GL89
enterobacter_NZ_GL89
enterobacter_NZ_GG70
enterobacter_NZ_GL89
In some embodiments, the oligonucleic acid probes provided by the invention are molecular inversion probes (MIP). Advantages that the MIP probes described herein offer over PCR include:
1) Multiplexing: there are published studies using 10k+ inversion probes to genotype humans including: http://www.ncbi.nlm.nih.gov/pubmed/17934468 (Porreca et. al.), 55k probes http://www.ncbi.nlm nih gov/pmc/articles/PMC2715272/?tool=pubmed 30k probes http://www.ncbi.nlm.nih.gov/pubmed/19329998 10k probes.
This offers a huge capability to expand panels. First uses might be to capture more rare strains/variants that work poorly with current PCR primers. Later uses might involve genotyping HIV and human loci as well as testing for diseases common in HIV patients—such a test can still be performed in a single tube with minimal per-test increase in reagents cost.
2) Specificity: the probes described herein are less likely to produce off-target products because the two probe arms must bind together. This provides a thermodynamic advantage for on-target binding compared to mis-priming. Furthermore, the exonuclease step will eliminate extension products that occur when only a single probe arm binds.
PCR primers can create long extension products that serve as templates for mis-priming in later rounds. This is particularly a problem when there's lots of background (e.g. human) DNA compared to the target sequence; such as when the exonuclease step didn't remove all of the template and the amplification/barcoding primers misprimed against human DNA. This ends up wasting reads and would have been worse had enrichment for the circularized probes was not being performed. Preventing such reads in a PCR-only system is difficult.
3) Design optimization: the large published datasets provide good training data for a probe picking algorithm. These large datasets can be useful for picking probe sets that will work reliably and with uniform efficiency. Furthermore, we can generate a set of 10k+ probes on a microarray to generate datasets using preferred enzymes. Currently being tested is the entire set of 10k+ probes in a single reaction and then analyzing the read counts to see what made a good probe and what didn't.
Understanding the probe behavior is important for pathogens as it helps to understand the sensitivity and specificity, particularly when considering rare strains or the possibility of previously unknown strains. Pathogenica has thermodynamic models of probe behavior that provide quantitative predictions of how well a probe will work against a target.
4) Simplicity: the probe protocol can be one-tube all the way through, adding reagents until all of the samples are pooled. PCR protocols often require multiple tubes to purify intermediate or final product from the template (e.g., Ampliseq requires 7, PCR+ Nextera likely requires 3+). Also being used are standard reagents (enzymes+oligos) and equipment (thermal cycler).
The following references are incorporated by reference in their entirety: Roberts R R, et al., “Costs attributable to healthcare-acquired infection in hospitalized adults and a comparison of economic methods,” Medical Care, 48(11):1026-1035, November 2010; Scott, R. D., II., “The Direct Medical Costs of Healthcare-Associated Infections in U.S. Hospitals and the Benefits of Prevention,” U.S. Centers for Disease Control and Prevention, March 2009; and Edwards, J. R., et al., National Healthcare Safety Network (NHSN) report: data summary for 2006 through 2008, issued December 2009, American Journal of Infection Control. 37:783-805, December 2009.
It should be understood that for all numerical bounds describing some parameter in this application, such as “about,” “at least,” “less than,” and “more than,” the description also necessarily encompasses any range bounded by the recited values. Accordingly, for example, the description at least 1, 2, 3, 4, or 5 also describes, inter alia, the ranges 1-2, 1-3, 1-4, 1-5, 2-3, 2-4, 2-5, 3-4, 3-5, and 4-5, et cetera.
For all patents, applications, or other reference cited herein, such as non-patent literature and reference sequence information, it should be understood that it is incorporated by reference in its entirety for all purposes as well as for the proposition that is recited. Where any conflict exits between a document incorporated by reference and the present application, this application will control. All information associated with reference gene sequences disclosed in this application, such as GeneIDs, Unigene IDs, or HomoloGene ID, or accession numbers (typically referencing NCBI accession numbers), including, for example, genomic loci, genomic sequences, functional annotations, allelic variants, and reference mRNA (including, e.g., exon boundaries or response elements) and protein sequences (such as conserved domain structures) are hereby incorporated by reference in their entirety.
Headings used in this application are for convenience only and do not affect the interpretation of this application.
Preferred features of each of the aspects provided by the invention are applicable to all of the other aspects of the invention mutatis mutandis and, without limitation, are exemplified by the dependent claims and also encompass combinations and permutations of individual features (e.g., elements, including numerical ranges and exemplary embodiments) of particular embodiments and aspects of the invention including the working examples. For example, particular experimental parameters exemplified in the working examples can be adapted for use in the claimed invention piecemeal without departing from the invention. For example, for material is that are disclosed, while specific reference of each various individual and collective combinations and permutation of these compounds may not be explicitly disclosed, each is specifically contemplated and described herein. Thus, if a class of elements A, B, and C are disclosed as well as a class of elements D, E, and F and an example of a combination of elements, A-D is disclosed, then even if each is not individually recited, each is individually and collectively contemplated. Thus, is this example, each of the combinations A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are specifically contemplated and should be considered disclosed from disclosure of A, B, and C; D, E, and F; and the example combination A-D. Likewise, any subset or combination of these is also specifically contemplated and disclosed. Thus, for example, the sub-group of A-E, B-F, and C-E are specifically contemplated and should be considered disclosed from disclosure of A, B, and C; D, E, and F; and the example combination A-D. This concept applies to all aspects of this application including, elements of a composition of matter and steps of method of making or using the compositions.
The forgoing aspects of the invention, as recognized by the person having ordinary skill in the art following the teachings of the specification, can be claimed in any combination or permutation to the extent that they are novel and non-obvious over the prior art—thus to the extent an element is described in one or more references known to the person having ordinary skill in the art, they may be excluded from the claimed invention by, inter alia, a negative proviso or disclaimer of the feature or combination of features.
While this invention has been particularly shown and described with references to example embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
Procedure:
Pathogenica Software installed on the Ion Torrent PGM reports the results.
This application claims the benefit of U.S. Provisional Application No. 61/637,185, filed Apr. 23, 2012. The entire teachings of the above application are incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2013/037833 | 4/23/2013 | WO | 00 |
Number | Date | Country | |
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61637185 | Apr 2012 | US |