NSF Award
0242162
The aim of this project is to make a comprehensive survey of complete sequences of large plasmids from the Bacillus cereus group of bacteria, which are ubiquitous constituents of natural soil environments, endosymbionts of insects, and animal pathogens. Perhaps the most well known member of the group is the organism, B. anthracis. In a theme common to the B. cereus group, key virulence genes, encoding lethal toxin and poly-glutamic acid capsule, that are responsible for the unique pathogenicity profile of B. anthracis are found on large plasmids (pXO1 and pXO2). Because plasmids play a major role in the biology of anthrax, a survey of large plasmids in up to 24 B. cereus group strains is proposed to answer specific questions about plasmids with and without known homologies to pXO1 and pXO2. These questions include: can evolutionary events that led to the creation of pXO1 and pXO2 be reconstructed and can sources for some of the genes on these plasmids be found in other B. cereus group organisms? To what extent does gene exchange between replicons occur and what are the mechanisms? Which pXO genes are unique in B. anthracis? Plasmids will be isolated from pulsed-field gels of genomic DNA and sequenced by whole-genome shotgun methods to produce finished, high-quality sequence. This project will significantly add to knowledge of how extrachromsomal elements influence key phenotypes of these important microorganisms. This is a Genome Sequencing Award funded through a collaborative program between the National Science Foundation and the Department of Agriculture.
