Desulfoluna limicola sp. nov., a sulfate-reducing bacterium isolated from sediment of a brackish lake

A novel sulfate-reducing bacterium, strain ASN36 T , was isolated from sediment of a brackish lake in Japan. Cells of strain ASN36 T were not motile and rod-shaped, with length of 2.0–4.9 μm and width of 0.6–0.9 μm. Growth was observed at 5–35 °C with an optimum growth temperature of 25–30 °C. The pH range for growth was 6.6–8.8 with an optimum pH of 7.3. Major fatty acids were C 16:1 ω 7 c and C 16:0 . Under sulfate-reducing conditions, strain ASN36 T utilized lactate, malate, pyruvate, butyrate, ethanol, butanol, glycerol, yeast extract and H 2 /CO 2 as growth substrate. Fermentative growth occurred on malate and pyruvate. The novel isolate used sulfate, sulfite and thiosulfate as electron acceptors. The genome of strain ASN36 T is composed of a chromosome with length of 6.3 Mbp and G + C content of 55.1 mol%. Analyses of the 16S rRNA gene indicated that strain ASN36 T is related to Desulfoluna species. Overall genome relatedness indices indicated that strain ASN36 T does not belong to any existing species. In contrast to the closest relatives, strain ASN36 T lacks genes for reductive dehalogenase required for organohalide respiration and does not use halogenated aromatics as electron acceptors. On the basis of its genomic and phenotypic properties, strain ASN36 T (= DSM 111985 T = JCM 39257 T ) is proposed as the type strain of a new species, Desulfoluna limicola sp. nov.