| dc.description.abstract | A bacterial infection popularized through bioterrorism, anthrax is a potentially fatal illness. Bacillus anthracis, notoriously the causative agent of anthrax, exists in community with hundreds of other species of bacteria in the environment, and is known to harbor in the rhizosphere of grass roots. Recent work done on the genetics of these communities has shown that B. anthracis shares a very high percentage of chromosomal genes with both B. thuringiensis and B. cereus, and that phenotypic differences between the bacterium results from extra-chromosomal DNA, usually plasmids. Therefore, the ability of B. anthracis to produce anthrax toxins is transmittable to other bacterium within its community, under the correct conditions. Following a literature review, I aimed to develop a model of bacterial conjugation within the Bacillus genus. I developed a spatially-explicit, individual-based, stochastic simulation model using NetLogo, an agent-based modeling language, for investigating the likelihood of detecting plasmids with genes encoding anthrax toxins within bacterial communities composed of B. anthracis, B. thuringiensis, B. cereus, and the surrounding matrix of extra-cellular polymeric substances. Model evaluation results indicate that the model shows promise as a simple, useful representation of the pertinent characteristics of the system of interest, and confirm the potential of the horizontal transfer of plasmids with genes encoding anthrax toxins among Bacillus species persisting outside the host as a proximate factor triggering anthrax epidemics. Further model demonstration has showed that the predictions and data produced by the model are compatible with data in the literature. | |
