Streptomyces rhizoryzae sp. nov., isolated from paddy rhizosphere soil and formal proposal to reclassify Streptomyces albulus as a later heterotypic synonym of Streptomyces noursei .

The taxonomic position of a novel actinomycete, designated strain RS10V-4, was determined using a polyphasic approach. Strain RS10V-4 was isolated from paddy rhizosphere soil of rice plant ( L.). The morphological, physiological and chemotaxonomic properties were consistent with its classification in the genus . On the basis of 16S rRNA gene sequence analysis, strain RS10V-4 belongs to the genus and had the highest sequence similarity to NBRC 15452 (98.3 %). The G+C content of the genomic DNA was 73.8 %. Digital DNA-DNA hybridization and average nucleotide identity values between the genome sequences of strain RS10V-4 and ATCC 11455 were lower than the recommendation threshold values for the recognition of species within the same genus. The whole-cell hydrolysates of strain RS10V-4 contained diaminopimelic acid as the diagnostic diamino acid and the whole-cell sugars were glucose and ribose. The predominant menaquinones were MK-9(H) and MK-9(H). The predominant cellular fatty acids (>10 %) were iso-C, anteiso-C, iso-C and iso-C. The polar lipids of strain RS10V-4 contained diphosphatidylglycerol, hydroxyphosphatidylethanolamine, phosphatidylethanolamine, phosphatidylinositol, an unidentified aminolipid, two unidentified lipids and an unidentified phospholipid. On the basis of these phenotypic and genotypic characteristics, it is supported that strain RS10V-4 represents a novel species of the genus , for which the name sp. nov. is proposed. The type strain is RS10V-4 (=TBRC 15167=NBRC 115345). In addition, the comparison of the whole genome sequences and phenotypic features suggested that and belong to the same species. Therefore, it is proposed that is reclassified as a later heterotypic synonym of .