DESULFOVIBRIO VIETNAMENSIS SP-NOV, A HALOPHILIC SULFATE-REDUCING BACTERIUM FROM VIETNAMESE OIL-FIELDS

From samples collected in crude oil storage tanks and oil production w aters near the coastal town of Vung Tau in Southern Vietnam, several s trains of sulfate-reducing bacteria were isolated and maintained in pu re culture. Strain G3 100 consisted of vibrio-shaped, motile, non-spor ulating, Gramnegative, desulfoviridin-containing cells. It grew optima lly at 5% NaCl. It utilized a range of organic acids as electron donor s in the presence of sulfate, including lactate, malate, formate and f umarate. Ethanol and glycerol were also used. In the presence of lacta te, thiosulfate, sulfite, sulfate and fumarate were used as electron a ccepters. Organic substrates were not fermented. The DNA base composit ion of G3 100 was 60.6 mol % G + C. On the basis of 16S rRNA sequence data, G3 100 should be included in the genus Desulfovibrio. However, i ts physiology, whole-cell protein pattern and susceptibility to antibi otics were different from other members of this genus. Therefore, G3 1 00 should be recognized as a new species, for which we propose the nam e Desulfovibrio vietnamensis. (C) 1996 Academic Press.