Abstract
A novel actinobacterium, designated as strain A1-08(T), was isolated from the volcanic soils of Mt. Mayon, Philippines. Phylogenetic analysis of the 16S rRNA gene sequence revealed that strain A1-08(T) belonged to the genus Streptomyces with sequence similarity with Streptomyces djakartensis NBRC 15409(T) (99.02%), Streptomyces tuirus NBRC 15617(T) (98.88%) and Streptomyces mutabilis NBRC 12800(T) (98.81%). Polyphasic characterization demonstrated distinct morphological, cultural, physiological and biochemical features with unique lipid and fatty acid profiles and respiratory quinones. The major phospholipids of strain A1-08(T) are diphosphatidylglycerol, phosphatidylethanolamine, glycophospholipid with mannose and/or galactose and unidentified lipids such as aminolipid and phospholipid. The major cellular fatty acids were anteiso-C(15 : 0), C(16 : 0), anteiso-C(17 : 0), iso-C(16 : 0), iso-C(15 : 0) and C(16 : 1) ω7c. The respiratory quinones of the strain include MK-9 (H6), MK-9 (H8), MK-10 (H6) and MK-10 (H8). Multilocus analysis using the concatenated sequences of atpD, gyrB, recA, rpoB and trpB showed that the strain formed a distinct branch in the genus Streptomyces. Potential genes for environmental stress response and adaptation were identified in the genome of strain A1-08(T) and its closest relative strains. Whole-genome sequencing confirmed A1-08(T) as a novel species within Streptomyces with 57.80% digital DNA-DNA hybridization and 93.03% average nt identity value with the closest type strain Streptomyces olivaceus NRRL B-3009(T). The name Streptomyces mayonensis sp. nov., derived from the Mayon Volcano in the Philippines, is hereby proposed (type strain A1-08(T) =JCM 36345, =DSM 118395).