Steptomyces fagopyri sp. nov., a novel actinomycete isolated from rhizospheric soil of Fagopyrum dibotrys

A novel actinomycete, designated strain QMT-28 T , was isolated from rhizosphere soil of Fagopyrum dibotrys collected from Shuangfeng, Hunan Province, PR China. Strain QMT-28 T grew well on International Streptomyces Project series media and formed well-developed, branched substrate hyphae and aerial mycelium that differentiated into loose spiral spore chains consisting of cylindrical spores with smooth surfaces. The diagnostic diamino acid was ll -diaminopimelic acid and the whole-cell sugars were galactose and glucose. The predominant fatty acids were C 18 : 1 cis 9, summed feature 6 (C 18 : 2 cis 9,12/C 18 : 0 a) and C 16 : 0 . The polar lipids included diphosphatidylglycerol, hydroxy phospatidylethanolamine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylinositol mannosides, phospholipids of unknown structure containing glucosamine and several unidentified phospholipids. The major menaquinones were MK-9, MK-9(H 2 ), MK-9(H 4 ), MK-9(H 6 ) and MK-9(H 8 ). The genome size of strain QMT-28 T was about 8.7 Mbp with a G+C content of 71.2 mol%. Phylogenetic analysis showed that the novel strain was closely related to Streptomyces olivochromogenes DSM 40451 T (99.5 % similarity), Streptomyces mirabilis NBRC 13450 T (98.9 %), Streptomyces kanamyceticus NBRC 13414 T (98.9 %), Streptomyces kaempferi I37 T (98.9 %) and Streptomyces arcticus ZLN234 T (98.8 %). However, the average nucleotide identity values, the digital DNA–DNA hybridization values and the multilocus sequence analysis evolutionary distances between this strain and closely related strains showed that it belonged to a distinct species. In addition, these results were also supported by differences in the phenotypic characteristics between QMT-28 T and five closely related type strains. Consequently, strain QMT-28 T should represent a novel species of the genus Streptomyces , with the suggested name Streptomyces fagopyri sp. nov. The type strain is QMT-28 T (=CICC 24808 T =JCM 33796 T ).