ISOLATION AND CHARACTERIZATION OF DESULFOVIBRIO-SENEZII SP. NOV., A HALOTOLERANT SULFATE REDUCER FROM A SOLAR SALTERN AND PHYLOGENETIC CONFIRMATION OF DESULFOVIBRIO-FRUCTOSOVORANS AS A NEW SPECIES

A new halotolerant Desulfovibrio, strain CVLT (T = type strain), was i solated from a solar saltern in California. The curved, gram-negative, nonsporeforming cells (0.3 x 1.0-1.3 mu m) occurred singly, in pairs, or in chains, were motile by a single polar flagellum and tolerated u p to 12.5% NaCl. Strain CVLT had a generation time of 60 min when grow n in lactate-yeast extract medium under optimal conditions (37 degrees C, pH 7.6, 2.5% NaCl). It used lactate, pyruvate, cysteine, or H-2/CO 2 + acetate as electron donors, and sulfate, sulfite, thiosulfate, or fumarate as electron accepters. Elemental sulfur, nitrate, or oxygen w ere not used. Sulfite and thiosulfate were disproportionated to sulfat e and sulfide. The G+C content of the DNA was 62 mol%. Phylogenetic an alysis revealed that Desulfovibrio fructosovorans was the nearest rela tive. Strain CVLT is clearly different from other Desulfovibrio specie s, and is designated Desulfovibrio senezii sp. nov. (DSM 8436).