Bailinhaonella thermotolerans gen. nov., sp. nov., a new member of the order Streptosporangiales

Abstract

A Gram-positive, aerobic, non-motile actinobacterium, designated YIM 75507^T, that was isolated from a soil sample collected from a dry-hot valley, was subjected to a polyphasic taxonomic study. The isolate formed branched hyphae and no fragmentation was found. Clustered spore chains were borne from aerial mycelium. The cell-wall peptidoglycan contained glutamic acid, alanine and meso-diaminopimelic acid. Whole-cell sugars were galactose, mannose, glucosamine, glucose and ribose. The major menaquinones were MK-9(H6), MK-9(H8) and MK-10(H6). The polar phospholipids contained phosphatidylmethylethanolamine, phosphatidylethanolamine and ninhydrin-positive phosphoglycolipid. Major fatty acids were iso-C16 : 0 and 10-methyl-C17 : 0. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 75507^T formed a stable and distinct lineage clustered with the genus Sinosporangium in the family Streptosporangiaceae. The draft genome sequence of strain YIM 75507^T exhibited low average nucleotide identity to the closest related strain, Sinosporangium album CPCC 201354^T (83.97 %), well below the 95-96 % species circumscription threshold. The G+C content of the genomic DNA was 73.8 mol%. On the basis of morphological, chemotaxonomic and phylogenetic evidence, strain YIM 75507^T is assigned to a novel species of a new genus, for which the name Bailinhaonella thermotolerans gen. nov., sp. nov. is proposed. The type strain of Bailinhaonella thermotolerans is YIM 75507^T (=KCTC 49229^T=CGMCC 4.7547^T).

Keywords: Bailinhaonella thermotolerans; dry-hot valley; polyphasic taxonomy.