Saccharopolyspora qinghaiensis sp. nov., a novel actinobacterium isolated from a salt lake.

Abstract

A novel halophilic, Gram-positive and aerobic actinobacterium, designated strain AFM 20147T, was isolated from a sediment sample collected from Xiaochaidan Salt Lake of Qinghai, China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain AFM 20147T belongs to the genus Saccharopolyspora, shows high sequence similarities to Saccharopolyspora griseoalba AFM 10238T (99.41%) and Saccharopolyspora halophila YIM 90500T (98.20%), and has low similarities (below 98.0%) with other members of the genus. The DNA-DNA relatedness values of strain AFM 20147T with S. griseoalba AFM 10238T and S. halophila YIM 90500T were 40 ± 1.7% and 37 ± 2.3%, respectively. Optimal growth was found to occur at 28°C, pH 7.5 and in the presence of 7.5% (w/v) NaCl. Strain AFM 20147T was found to contain meso-diaminopimelic acid as the cell wall diamino acid, and galactose and arabinose as the whole cell sugars. The major fatty acids were identified as iso-C15:0, iso-C16:0 and anteiso-C17:0. The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylinositol and phosphatidylcholine. MK-9(H4) was found to be the predominant menaquinone and the DNA G+C content was determined to be 67.8mol%. DNA-DNA relatedness data, together with phenotypic and chemotaxonomic differences, clearly distinguish the isolate from its close neighbours. On the basis of the data from this polyphasic analysis, a novel species Saccharopolyspora qinghaiensis sp. nov. is proposed. The type strain is S. qinghaiensis AFM 20147T (=KCTC 49190T =CGMCC 4.7556T).