Ornithinimicrobium sediminis sp. nov., a novel actinobacterium isolated from a saline lake sediment.

Abstract

An actinobacterium, designated strain EGI L100131T, was isolated from saline lake sediment in Xinjiang Province, China. The taxonomic position of the isolate was determined using analysis based on the polyphasic taxonomy and phylogenomics. Phylogenetic analysis and 16S rRNA gene sequence similarities indicated that strain EGI L100131T formed a distinct clade with Ornithinimicrobium murale DSM 22056T and Ornithinimicrobium cavernae CFH 30183T, and shared sequence identities of 97.8% and 97.0%, respectively. The novel isolate could be distinguished from other species of the genus Ornithinimicrobium by its distinct phenotypic, physiological, and genotypic characteristics. Cells of strain EGI L100131T were aerobic, Gram-staining positive, and coccoid to rod-shaped. Optimal growing conditions of strain EGI L100131T occurred at pH 8.0 and 28 ºC. Ornithine was the diagnostic diamino acid in the cell-wall peptidoglycan. The respiratory quinone was MK-8 (H4), while the major fatty acids (> 10%) were C17:1 ω8c, C17:0, iso-C16:0, and iso-C15:0. The detected polar lipids included diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, and a glycophospholipid. The G + C content based on genomic DNA was 71.5%. According to the phenotypic, physiological, genotypic, and phylogenetic data, strain EGI L100131T represents a new species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium sediminis sp. nov. is proposed. The type strain is EGI L100131T (= KCTC 49716T = CGMCC 1.19241T).