Streptomyces caldifontis sp. nov., isolated from a hot water spring of Tatta Pani, Kotli, Pakistan

A Gram-staining positive, non-motile, rod-shaped, catalase positive and oxidase negative bacterium, designated NCCP-1331, was isolated from a hot water spring soil collected from Tatta Pani, Kotli, Azad Jammu and Kashmir, Pakistan. The isolate grew at a temperature range of 18-40 °C (optimum 30 °C), pH 6.0–9.0 (optimum 7.0) and with 0–6 % NaCl (optimum 2 % NaCl (w/v)). The phylogenetic analysis based on 16S rRNA gene sequence revealed that strain NCCP-1331 belonged to the genus Streptomyces and is closely related to Streptomyces brevispora BK160 with 97.9 % nucleotide similarity, followed by Streptomyces drosdowiczii NRRL B-24297 with 97.8 % nucleotide similarity. The DNA–DNA relatedness values of strain NCCP-1331 with S. brevispora KACC 21093 and S. drosdowiczii CBMAI 0498 were 42.7 and 34.7 %, respectively. LL-DAP was detected as diagnostic amino acid along with alanine, glycine, leucine and glutamic acid. The isolate contained MK-9(H) as the predominant menaquinone. Major polar lipids detected in NCCP-1331 were phosphatidylethanolamine, phosphatidylinositol and unidentified phospholipids. Major fatty acids were iso-C, summed feature 8 (18:1 ω7c/18:1 ω6c), anteiso-C and C. The genomic DNA G + C content was 69.8 mol %. On the basis of phylogenetic, phenotypic and chemotaxonomic analysis, it is concluded that strain NCCP-1331 represents a novel species of the genus Streptomyces, for which the name Streptomyces caldifontis sp. nov. is proposed. The type strain is NCCP-1331 (=KCTC 39537 = CPCC 204147).