Calidifontibacter indicus gen. nov., sp. nov., a member of the family Dermacoccaceae isolated from a hot spring, and emended description of the family Dermacoccaceae

Abstract

During the course of a study on the bacterial diversity in Western Ghats, India, an actinobacterial strain, designated PC IW02T, was isolated and characterized by a polyphasic taxonomic approach. Strain PC IW02T was a non-motile, Gram-positive, short rod that formed creamish white to yellow coloured colonies. 16S rRNA gene sequence analysis showed that the novel strain showed highest sequence similarity with type strains of members of the genus Dermacoccus: Dermacoccus barathri (96.6 %), Dermacoccus profundi (96.5 %), Dermacoccus abyssi (96.4 %) and Dermacoccus nishinomiyaensis (95.9 %). The phylogenetic tree suggested that strain PC IW02T could represent a member of a new genus of the family Dermacoccaceae with the genus Demetria as closest clade. Pairwise sequence alignment with Demetria terragena HKI 0089T and Kytococcus sedentarius DSM 20547T showed similarities of 94.2 and 93.7 %, respectively. Strain PC IW02T had MK-8(H4) as the major menaquinone. The major fatty acids were iso-C16 : 0 (43.4 %), iso-C16 : 1 H (17.2 %) and anteiso-C17 : 0 (9.9 %). The diagnostic cell-wall amino acid at position 3 of the peptide subunit was lysine; the interpeptide bridge consisted of Gly–Ser–Asp. The polar lipids present were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannosides and phosphatidylserine, along with two unknown phospholipids. The genomic DNA G+C content of the isolate was 77 mol%. On the basis of phenotypic characteristics, including chemotaxonomic data, and 16S rRNA gene sequence similarities, strain PC IW02T represents a novel species in a new genus of the family Dermacoccaceae for which the name Calidifontibacter indicus gen. nov., sp. nov. is proposed. The type strain of Calidifontibacter indicus is PC IW02T ( = MTCC 8338T = DSM 22967T = JCM 16038T). An emended description of the family Dermacoccaceae is provided.