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

An actinobacterium, designated strain EGI L100131(T), 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 L100131(T) formed a distinct clade with Ornithinimicrobium murale DSM 22056(T) and Ornithinimicrobium cavernae CFH 30183(T), 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 L100131(T) were aerobic, Gram-staining positive, and coccoid to rod-shaped. Optimal growing conditions of strain EGI L100131(T) 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 (H-4), while the major fatty acids (> 10%) were C-17:1 omega 8c, C-17:0, iso-C-16:0, and iso-C-15:0. 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 L100131(T) represents a new species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium sediminis sp. nov. is proposed. The type strain is EGI L100131(T) (= KCTC 49716( T) = CGMCC 1.19241(T)).

Automated summary

A new actinobacterium strain, Ornithinimicrobium sediminis sp. nov., was isolated from saline lake sediment in Xinjiang Province, China. It formed a distinct clade with Ornithinimicrobium murale and Ornithinimicrobium cavernae based on phylogenetic analysis and 16S rRNA gene sequence similarities. The strain exhibited unique phenotypic, physiological, and genotypic characteristics, distinguishing it from other species of the genus Ornithinimicrobium.