The goal of the proposed research is to characterize newly-discovered gliding motility in bacteria of the Bacillus cereus group. The B. cereus group, which includes pathogens of humans (B. cereus and B.anthracis) and insects (B. thuringiensis), are quite variable in motility as measured on agar surfaces. We have found that B. cereus and B. thunngiensis exhibit very rapid phospholipid- or surfactant-induced glidingmotility, independent of flagella and akin to the gliding/twitching motility seen in Gram-negative bacteria. Motility has been shown to be a key component of the pathogenicity of a variety of Gram-negative bacteria,and this may also be true for the B. cereus group. In B. thuringiensis we have also found that thephospholipid-induced motility is regulated by the plcR regulon, which is known to control the expression ofnumerous pathogenicity genes in B. thuringiensis as well as B. cereus. Our experimental plan, focusing onthe B. cereus group, will be complemented by genome sequences of B. cereus and B. thuringiensis whichare nearing completion.
Specific aims i nclude: (1) basic characterization of phospholipid-induced glidingmotility in the B. cereus family; and (2) identification of genes essential for gliding motility in B. cereus and B.thuringiensis including analysis of the control of gliding by the plcR regulon. The work proposed here willprovide fundamental, new information on the phenomenon of phospholipid-induced gliding motility in B.cereus and B. thuringiensis, identification of genes essential for gliding motility, and location of such genes inthe B. cereus family genomes and comparison to other known bacterial genes. Such information will be thebasis for future studies or the biochemical mechanism of gliding motility in B. cereus family, and may lead to new strategies to control tissue invasion by these pathogens.
| Fall, Ray; Kearns, Daniel B; Nguyen, Tam (2006) A defined medium to investigate sliding motility in a Bacillus subtilis flagella-less mutant. BMC Microbiol 6:31 |
| Kinsinger, Rebecca F; Kearns, Daniel B; Hale, Marina et al. (2005) Genetic requirements for potassium ion-dependent colony spreading in Bacillus subtilis. J Bacteriol 187:8462-9 |
