Interactions between microorganisms and the environment. Topics include methods of sampling various environments, methods for monitoring microbial activities, petroleum microbiology, bioremediation, survival of airborne microorganisms, microbial metabolism of selected pollutants. Prerequisite: MICRB 265, corequisite: a 300-level Biological Sciences course or consent of Instructor. Note: Credit can be received in only one of MICRB 391, 491 and 591.