The process by which plants and some bacteria can convert light energy to sugar, or photosynthesis, is crucial to global food webs, and complicated. Very little is known about the photosynthetic bacteria in the purple sulfur bacteria group, which may represent one of the most primitive photosynthetic organisms and are capable of carbon fixation and sequestration in both light and dark conditions with the help of sulfur compounds. Purple sulfur bacteria are autotrophic and can synthesize organic compounds from inorganic sources. Researchers hope to learn more by sequencing nine type strains of purple sulfur bacteria that are found in freshwater, brackish and marine systems. The information would lead to a better understanding of the process of photosynthesis as well as the global carbon and sulfur cycles. Additionally, some of these bacteria may be members of phototrophic mats in geothermal environments and thus may play key roles in these microbial communities.
The nine strains of purple sulfur bacteria in this project come from two families. As purple sulfur bacteria haven’t been fully studied, these strains would fill in gaps of knowledge regarding these bacteria much like the DOE JGI’s Genome Encyclopedia of Bacteria and Archaea (GEBA) project seeks to fill in phylogenetic gaps in the Tree of Life.
Photo: Chromatium okenii by Raymond Cox, University of Southern Denmark
Principal Investigators: Donald Bryant, Penn State University
Program: CSP 2010