Bioterrorism and the alarming spread of antibiotic resistant bacteria are but two of the reasons for the renewed emphasis on the biology of microorganisms. This course will examine microbes from the perspectives of cell structure and function, genetics, and evolution. A major theme will be the adaptation of bacteria as they evolve to fill specific ecological niches, with an emphasis on microbe: host interactions that lead to pathogenesis. We will consider communication among bacteria as well as between bacteria and their environment. Topics include: microbial development, stress response, bioremediation, bacteriophages, subversion of the immune defenses, and genomics. In the lab, students will examine the regulation of bacterial gene expression, horizontal gene transfer, the isolation and characterization of bacteria from natural environment, and carry out independent projects. Readings will be supplemented by articles from the primary literature. Evaluation will be based on three exams, a paper, lab reports, and a presentation. Prerequisites: Biology 202. Enrollment limit: 24 (expected: 16). Preference given to junior and then to senior Biology majors.