Desulfobulbus

Desulfobulbus is a genus of sulfate-reducing bacteria (SRB) in the family Desulfobulbaceae, within the order Desulfobacterales of the class Deltaproteobacteria, phylum Proteobacteria. Members are typically found in anaerobic environments where sulfate is available and organic matter is present.

These organisms are obligate anaerobes that perform dissimilatory sulfate reduction, using sulfate as the terminal electron acceptor while oxidizing a variety of organic substrates. Common electron donors include propionate, acetate, lactate, ethanol, and other fatty acids, with energy conserved through the formation of hydrogen sulfide.

Morphology among Desulfobulbus species is generally slender, curved to straight Gram-negative rods. Many species are motile, often equipped with flagella, though cell appearance can vary across the genus.

Ecologically, Desulfobulbus is widespread in marine and freshwater sediments, oil reservoirs, anaerobic digesters, and other anaerobic zones where reduced sulfur compounds can be produced. Through their sulfate-reducing activity, these bacteria contribute to the sulfur cycle and can influence metal corrosion and souring in industrial contexts.

A well-characterized species is Desulfobulbus propionicus, a propionate-oxidizing SRB used as a model organism for studying metabolite flux in sulfate reduction. Genomic studies across Desulfobulbus members have highlighted the presence of the classical dissimilatory sulfate-reduction pathway genes, such as dsrAB and aprAB, and several genomes have been sequenced.

Desulfobulbus is not considered pathogenic to humans and is primarily of interest for understanding anaerobic microbial ecology, biogeochemical cycling, and applications in bioremediation and industry.