Streptomyces guryensis sp. nov. exhibiting antimicrobial activity, isolated from riverside soil

A novel Gram-stain-positive, aerobic actinobacterial strain designated NR30 T was isolated from riverside soil. A polyphasic approach was employed for the taxonomic characterization of NR30 T . The strain developed extensively branched light brown to light pink substrate mycelia and light grey aerial mycelia, and produced spiny spores in loose spiral spore chains on ISP 3 and 4 agars. NR30 T grew at 10–40°C (optimum, 30°C), at pH 6.0–9.0 (optimum, pH 8.0) and in the presence of 0–3 % NaCl (optimum, 0 %). Analysis of 16S rRNA gene sequences indicated that NR30 T represents a member of the genus Streptomyces . NR30 T shared the highest 16S rRNA gene sequence similarity with Streptomyces cyaneus NRRL B-2296 T (98.6 %). On the basis of orthologous average nucleotide identity, NR30 T was most closely related to Streptomyces panaciradicis NBRC 109811 T with 86.3 % identity. The results of the digital DNA–DNA hybridization analysis also indicated low levels of relatedness with other species, as the highest value was observed with Streptomyces panaciradicis NBRC 109811 T (31.1 %). The major fatty acids of the strain were anteiso-C 15 : 0 , C 16 : 0 , iso-C 16 : 0 and anteiso-C 17 : 0 . The major respiratory quinones were MK-9(H 8 ) and MK-9(H 6 ). The diagnostic polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol mannoside. The major cell wall diamino acid was ll -diaminopimelic acid, and the characteristic whole-cell sugars were rhamnose, ribose and glucose. The DNA G+C content was 70.3 mol %. NR30 T exhibited antimicrobial activity against several Gram-negative bacteria and yeasts. On the basis of the results of both phenotypic and phylogenetic analyses, strain NR30 T evidently represents a novel species of the genus Streptomyces , and the name Streptomyces guryensis sp. nov. (type strain=NR30 T =KCTC 49653 T =LMG 32476 T ) is proposed accordingly.