Microbial Physiology Research Interests Membranes form the structural and functional limits of the cell. Membranes separate the cellular contents from the environment and are the site of many essential activities such as energy transduction and the initiation of responses to environmental stimuli. My research interests center on the molecular events involved in membrane development. My students and I are studying this in two model systems - phototrophic bacteria and methanotrophic bacteria. In both cases the formation of this membrane is affected by environmental conditions thus allowing laboratory manipulation of membrane formation.
Phototrophic bacteria use light as a source of energy.
Using biochemical, immunochemical, ultrastructural, genetic and molecular approaches, work from my laboratory has demonstrated that the ICM and cytoplasmic membrane are continuous and that when triggered by environmental stimuli, the ICM arises from invagination and differentiation of the cytoplasmic membrane. The pigment-binding proteins are required for ICM formation. We have cloned the genes encoding the pigment-binding proteins, made mutants in vitro , and evaluated the effects of these mutations in vivo . These studies demonstrated that these proteins are required for ICM formation and has led to the hypothesis that insertion of these proteins in the membrane is a stimulus for membrane proliferation. We are currently evaluating the role of structural aspects of these proteins in membrane biogenesis .