Geodermatophilus maliterrae sp. nov., a member of the Geodermatophilaceae isolated from badland surfaces in the Red Desert, Wyoming, USA.

Abstract

A novel Gram-stain-positive, black-pigmented bacterium, designated as WL48A ^T, was isolated from the surface of badland sedimentary rock in the Red Desert of Wyoming and characterized using a polyphasic taxonomic approach. Good growth occurred at 28-32 °C, pH 7-9, and NaCl less than 1% (w/v). Colonies, growing well on International Streptomyces Project media (ISP) 3 and ISP 7, were black and adhering to the agar. Phylogenetic analyses based on 16S rRNA gene and draft genome sequences showed that strain WL48A^T belongs to the family Geodermatophilaceae, forming a distinct sub-branch with Geodermatophilus bullaregiensis DSM 46841^T. The organism showed 16S rRNA gene sequence similarity of 98.8% with G. bullaregiensis DSM 46841^T. Digital DNA-DNA hybridization value between the genome sequences of strain WL48A ^T and G. bullaregiensis DSM 46841^T was 51.8%, below the threshold of 70% for prokaryotic species delineation. The chemotaxonomic investigation revealed the presence of galactose, glucose, mannose, xylose and ribose as well as meso-DAP in the peptidoglycan layer. The polar lipid profiles contained phosphatidylcholine (PC), phosphatidylinositol (PI), diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE) phosphoglycolipid, phospholipids and an unidentified lipid. The menaquinone profile consisted of MK-9(H₄) (98.2%) and MK-9(H₂) (10.8%). The major fatty acid profile (>15%) comprised iso-C_15 : 0 and iso-C_16 : 0. Based on phenotypic, genetic and genomic data, strain WL48A^T (=DSM 116197^T = NCIMB 15483^T=NCCB 100957^T =ATCC TSD-376^T) merits to be considered as a novel species for which the name Geodermatophilus maliterrae sp. nov. is proposed.