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

A novel alkalitolerant, sulphate-reducing bacterium (strain RT2(T)) was isolated from alkaline district heating water. Strain RT2(T) was a motile vibrio (0(.)5-0(.)8 mu m wide and 1(.)4-1(.)9 mu m 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 DNAG+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 RT2(T) (=DSM 16529(T)=jCM 12612(T)). The strain is the first alkali-tolerant member of the genus Desulfovibrio to be described.