Pure Culture of Syntrophus buswellii, Definition of its Phylogenetic Status, and Description of Syntrophus gentianae sp. nov

The syntrophically benzoate-oxidizing anaerobic bacterium Syntrophus bustvellii was grown in pure culture in a defined mineral medium with crotonate as sole substrate, which was fermented stoichiometrically to acetate and butyrate. This pure culture, as well as that of another benzoate-oxidizing syntrophic bacterium, strain HQGö1, both were analyzed for possible phylogenetic relatedness on the basis of total 16S rRNA sequence analysis. Both strains turned out to be closely related and clustered in the δ subgroup of the Proteobacteria with sulfate-reducing bacteria. Strain HQGö1, which can be grown in pure culture with either hydroquinone or gentisic acid, is described as a new species of the genus Syntrophus, S. gentianae sp. nov.