Streptomyces montanisoli sp. nov., exhibiting antimicrobial activity, isolated from mountain soil around a decaying tree

A Gram-stain-positive, aerobic actinobacterial strain designated MMS17-BM035(T) isolated from mountain soil around a decaying tree was subjected to taxonomic characterization. The isolate developed extensively branched substrate mycelia and white aerial hyphae on International Streptomyces Project 2 agar. Strain MMS17-BM035(T) grew at 15-34 degrees C (optimum, 30 degrees C), at pH 5.0-8.0 (optimum, pH 7.0) and in the presence of 0-6 % NaCl (optimum, 0 %). Analysis of 16S rRNA gene sequences indicated that MMS17-BM035T fell into a phylogenetic cluster belonging to the genus Streptomyces . MMS17-BM035(T) shared the highest sequence similarity of 99.45 % with Streptomyces fuscigenes JBL-20(T), and no higher than 98.7 % with other species of Streptomyces . Based on the orthologous average nucleotide identity, MMS17-BM035(T) was again mostly related to S. fuscigenes JBL-20(T) with 84.14 % identity, and less than 80 % with other species. The digital DNA-DNA hybridization analysis also indicated low levels of relatedness with related species, as the highest value was observed with S. fuscigenes JBL-20(T) (28.8 %). The major fatty acids of the strain were anteiso-C-15 : 0, a summed feature (consisting of C-18 : 1 omega 7c/C-18 : 1 omega 6c), iso-C-15 : 0, C-16 : 0 and C-20 : 0. The major respiratory quinones were MK-9(H-4) and MK-9(H-6). The diagnostic polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositolmannoside. The major cell-wall diamino acid was LL-diaminopimelic acid, and the characteristic whole-cell sugars were glucose and ribose. The DNA G+C content was 72.1 mol%. Strain MMS17-BM035(T) exhibited antimicrobial activity against several Gram-positive bacteria and yeasts. Based on both phenotypic and phylogenetic evidences, strain MMS17-BM035(T) should be classified as representing a novel species, for which the name Streptomyces montanisoli sp. nov. (type strain=MMS17-BM035(T)=KCTC 49544(T)=JCM 34528(T)) is proposed.