Genetic and Proteomic Studies of Sulfur Oxidation in Chlorobium tepidum (syn. Chlorobaculum tepidum)

Abstract

The oxidation of reduced sulfur compounds is perhaps the most poorly understood physiological process carried out by the green sulfur bacteria (the Chlorobiaceae). My laboratory is testing models of sulfur oxidation pathways in the model system Chlorobium tepidum (ATCC 49652 syn. Chlorobaculum tepidum (Imhoff, 2003) ) by the creation and analysis of mutant strains lacking specific gene products. The availability of a complete, annotated genome sequence for C. tepidum enables this approach, which will specify targets for biochemical analysis by indicating which genes are important in an organismal context. This is particularly important when several potentially redundant enzymes are encoded by the genome for a particular reaction, such as sulfide oxidation. Additionally, we are using proteomics approaches to define the subcellular locations of proteins involved in sulfur oxidation pathways. The results produced by this research will refine models of anaerobic sulfur oxidation pathways and their integration into the global physiology of the Chlorobiaceae.