Sulfurovum sp. SCGC AAA036-B05 Genome sequencing

Epsilonproteobacteria play essential roles in a variety of environments in catalyzing reactions of relevance for the biogeochemical cycling of carbon, sulfur, and nitrogen. By catalyzing redox reactions they are important in controlling the speciation of metals with affects on solubility and toxicity. At deep-sea vents epsilonproteobacteria are continuously exposed to high concentrations of potentially toxic compounds, like sulfide, heavy metals, mercury, and genomic analyses have revealed adaptations that these organisms have developed to cope with such conditions. Obtaining genomic information on the numerically abundant, but so-far uncultivated epsilonproteobacteria has the potential to reveal novel adaptations and thus potential implications in bioremediation. Epsilonproteobacteria use the reductive TCA cycle for carbon fixation, an ancient and more efficient carbon fixation pathway than the well-known Calvin cycle. Epsilonproteobacteria can fix inorganic carbon under conditions that many other organism currently considered for carbon sequestration cannot tolerate. Thus, the investigation of these organisms and the use of alternative carbon fixation pathways like the rTCA cycle is also an area of high relevance for DOE. In the past great attention has been given to organisms utilizing the CBB cycle for carbon fixation. However, these organisms might not be always the best choice for all environmental conditions where carbon sequestration would be beneficial. Many epsilonproteobacteria use the oxidation of molecular hydrogen as an energy source, either coupled to the reduction of oxygen, nitrate, or sulfur. Discovery of novel hydrogenases as part of the proposed sequencing efforts is expected, with implications for the use of these enzymes in biofuel production and energy related applications.