Phylogenetic position and chemotaxonomic characteristics of the thermophilic sulfate-reducing bacterium Desulfotomaculum kuznetsovii

A partial nucleotide sequence of the 16S rRNA gene and the fatty-acid compo sition of cellular lipids were determined for the Desulfotomaculum kuznetso vii type strain 17. Comparison of this 16S rRNA sequence with those of othe r thermophilic spore-forming sulfate-reducing bacteria confirmed the taxono mic status of Dtm. kuznetsovii as a separate species. An unusual simultaneo us presence of odd-numbered branched-chain (iC15 : 0, iC17 : 0) and even-nu mbered straight-chain (C16 : 0, C18 : 0) fatty acids, as well as of iC17, i C15, C15, and C17 aldehydes, in the composition of its cellular lipids dist inguishes Dtm. kuznetsovii from other thermophiles of the genus Desulfotoma culum and can be considered an important differentiating feature.