Streptomyces yaizuensis sp. nov., a berninamycin C-producing actinomycete isolated from sponge

While screening for antibiotics in a marine sample, we discovered a berninamycin C-producing actinomycete, designated YSPA8^T, isolated from a sponge. A polyphasic approach was used to determine the taxonomic position of the strain. Strain YSPA8^T formed sympodially branched aerial mycelia that ultimately segment into chains of spores. Comparative and phylogenetic analyses of the 16S rRNA gene sequence showed that strain YSPA8^T were closely related to Streptomyces clavuligerus ATCC 27064^T (99.66%), Streptomyces amakusaensis NRRL B-3351^T (98.69%), Streptomyces inusitatus NBRC 13601^T (98.48%), and 'Streptomyces jumonjinensis' JCM 4947 (98.41%). The phylogenetic tree using the 16S rRNA gene sequences, and both phylogenomic trees suggested that the closest relative of strain YSPA8^T was S. clavuligerus ATCC 27064^T. The average nucleotide identity, digital DNA-DNA hybridization, and average amino acid identity values between strain YSPA8^T and S. clavuligerus ATCC 27064^T were 84.1%, 28.9%, and 82.5%, respectively, which were below the thresholds of 95%, 70%, and 95% for a prokaryotic conspecific assignment. The G + C of the strain YSPA8^T was 72.6%. Whole-cell hydrolysates of strain YSPA8^T contained LL-diaminopimelic acid. The predominant menaquinones were MK-9(H₆) (49%) and MK-9(H₈) (48%), and the major fatty acids were C_16:0 (26.8%), C_16:1 ω7c/ω6c (17.2%), iso-C_16:0 (16.0%), and iso-C_15:0 (12.5%). The major phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, and other unidentified phospholipids. Based on the phenotypic, phylogenetic, genomic, and chemotaxonomic data, strain YSPA8^T represents a novel species of the genus Streptomyces, and the proposed name for this species is Streptomyces yaizuensis sp. nov. The type strain is YSPA8^T (=NBRC 115866^T = TBRC 17196^T).