%0 Journal Article %A Miroshnichenko, M. L. %A Rainey, F. A. %A Hippe, H. %A Chernyh, N. A. %A Kostrikina, N. A. %A Bonch-Osmolovskaya, E. A. %T Desulfurella kamchatkensis sp. nov. and Desulfurella propionica sp. nov., new sulfur-respiring thermophilic bacteria from Kamchatka thermal environments %D 1998 %J International Journal of Systematic and Evolutionary Microbiology, %V 48 %N 2 %P 475-479 %@ 1466-5034 %R https://doi.org/10.1099/00207713-48-2-475 %K sulfur-respiring bacteria %K Desulfurella kamchatkensis sp. nov %K Desulfurella propionica sp. nov %K thermophilic bacteria %I Microbiology Society, %X Two strains of moderately thermophilic bacteria, which reduce elemental sulfur to hydrogen sulfide, were isolated from volcanic sources in Kamchatka. Strain K-119Twas obtained from a thermophilic microbial community associated with Thermothrix thiopara, and strain U–8Twas isolated from a cyanobacterial mat inhabiting a sulfide-rich hot spring. Cells of both strains are short Gram-negative rods, motile with one polar flagellum (strain K–119T) or non-motile (strain U–8T). Both strains are obligate anaerobes, have temperature optima of 54–55 °C and pH optima of 6.9-7.2. Molecular hydrogen, acetate, fumarate, malate, pyruvate, lactate and long-chain saturated fatty acids served as growth substrates for both species; strain U-8Twas also able to grow on propionate. All substrates were oxidized completely, H2S and CO2 being the only metabolic products. Elemental sulfur was obligately required for growth of strain K–119T, whereas strain U-8Twas able to grow also with thiosulfate as electron acceptor and on pyruvate without an external electron acceptor. The DNA G+C contents of strains K–119Tand U–8Twere 31.6 and 32.2 mol%, respectively. Phenotypic features and the results of 16S rRNA sequencing indicate the affiliation of the new isolates to the genus Desulfurella. The DNA-DNA hybridization with Desulfurella acetivorans was 40% for strain K–119Tand 55% for strain U-8T; the DNA-DNA hybridization between the new isolates was 32%. Based on the results of morphological, physiological and phylogenetic studies the following two new species are proposed: Desulfurella kamchatkensis sp. nov. with the type strain K–119T(= DSM 10409T) and Desulfurella propionica sp. nov. with the type strain U–8T(=DSM 10410T). %U https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/00207713-48-2-475