Desulfosporosinus hippei sp. nov., a mesophilic sulfate-reducing bacterium isolated from permafrost.

The sulfate-reducing strain 343T was isolated from ancient permafrost deposits in Siberia, Russia. Based on 16S rRNA gene sequence analyses, this strain was closely related to Desulfosporosinus species, showing 97.9 % 16S rRNA gene sequence similarity to Desulfosporosinus meridiei DSM 13257T, 97.6 % similarity to Desulfosporosinus auripigmenti DSM 13351T, 97.2 % similarity to Desulfosporosinus lacus DSM 15449T and 96.2 % similarity to Desulfosporosinus orientis DSM 765T. The strain was found to contain b-type cytochromes and to reduce only sulfate and thiosulfate using lactate as an electron donor but not sulfite, elemental sulfur, fumarate, nitrate or Fe(III). These data, considered in conjunction with DNA-DNA hybridization data, cell-wall chemotaxonomy and data on physiology, support recognition of strain 343T as representing a distinct and novel species within the genus Desulfosporosinus, namely Desulfosporosinus hippei sp. nov., with the type strain 343T (=DSM 8344T =VKM B-2003T).