Microlunatus speluncae sp. nov., a novel actinobacterium isolated from a Karstic subterranean environment sample
A novel actinobacterial strain, designated SYSU K12189T, was isolated from a soil sample collected from a Karst cave in Xingyi county, Guizhou province, south-western China. The taxonomic position of the strain was investigated using a polyphasic approach. Cells of the strain were observed to be aerobic and Gram-stain positive. On the basis of 16S rRNA gene sequence similarities and phylogenetic analysis, strain SYSU K12189T is closely related to the type strains of the genus Microlunatus, Microlunatus parietis 12-Be-011T (98.5% sequence similarity), Microlunatus nigridraconis CPCC 203993T (98.4%) and Microlunatus cavernae YIM C01117T (96.6%), and is therefore considered to represent a member of the genus Microlunatus. DNA–DNA hybridization values between strain SYSU K12189T and related type strains of the genus Microlunatus were < 70%. In addition, LL-diaminopimelic acid was found to be the diagnostic diamino acid in the cell wall peptidoglycan. The major isoprenoid quinone was identified as MK-9(H4), while the major fatty acids (> 10%) were found to be anteiso-C15:0, iso-C15:0, iso-C16:0 and iso-C14:0. The polar lipids were found to contain diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, three glycolipids and two unidentified lipids. The genomic DNA G+C content of strain SYSU K12189T was determined to be 69.4 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain SYSU K12189T is concluded to represent a novel species of the genus Microlunatus, for which the name Microlunatus speluncae sp. nov. is proposed. The type strain is SYSU K12189T (= KCTC 39847T = DSM 103947T).
KeywordsMicrolunatus speluncae sp. nov. Limestone sample Karst cave Polyphasic taxonomy
WJL, YGX and BZF designed research and project outline. MXH, LK LL and YGX performed isolation, deposition and identification. JYJ and XTZ performed genome analysis. BZF and WJL drafted the manuscript. All authors read and approved the final manuscript.
This research was supported by National Key R&D Program of China (2017YFD0200503), Natural Science Foundation of China (No. 31600015) and National Fundamental Fund Project Subsidy Funds of Personnel Training of China (No. J1310025).
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Conflict of interest
All the authors have declared no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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