Desulfovibrio alkalitolerans sp. nov., a novel alkalitolerant, sulphate-reducing bacterium isolated from district heating water.

A novel alkalitolerant, sulphate-reducing bacterium (strain RT2T) was isolated from alkaline district heating water. Strain RT2T was a motile vibrio (0.5-0.8 microm wide and 1.4-1.9 microm long) and grew at pH 6.9-9.9 (optimum at pH 9.0-9.4) and at 16-47 degrees C (optimum at 43 degrees C). The genomic DNA G+C content was 64.7 mol%. A limited number of compounds were used as electron donors with sulphate as electron acceptor, including lactate, pyruvate, formate and hydrogen/acetate. Sulphite and thiosulphate also served as electron acceptors. Based on physiological and genotypic properties, the isolate was considered to represent a novel species of the genus Desulfovibrio, for which the name Desulfovibrio alkalitolerans sp. nov. is proposed. The type strain is RT2T (=DSM 16529T=JCM 12612T). The strain is the first alkali-tolerant member of the genus Desulfovibrio to be described.