Verrucosispora rhizosphaerae sp. nov., isolated from mangrove rhizosphere soil

An actinomycete strain, 2603PH03^T, was isolated from a mangrove rhizosphere soil sample collected in Wenchang, China. Phylogenetic analysis of the 16S rRNA gene sequence of strain 2603PH03^T indicated high similarity to Verrucosispora gifthornensis DSM 44337^T (99.4%), Verrucosispora andamanensis (99.4%), Verrucosispora fiedleri MG-37^T (99.4%) and Verrucosispora maris AB18-032^T (99.4%). The cell wall was found to contain meso-diaminopimelic acid and glycine. The major menaquinones were identified as MK-9(H₄), MK-9(H₆) and MK-9(H₈), with MK-9(H₂), MK-10(H₂), MK-9(H₁₀) and MK-10(H₆) as minor components. The characteristic whole cell sugars were found to be xylose and mannose. The phospholipid profile was found to contain phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phosphatidylserine and an unidentified phospholipid. The DNA G+C content was determined to be 70.1 mol%. The results of physiological and biochemical tests and low DNA-DNA relatedness readily distinguished the isolate from the closely related species. On the basis of these phenotypic and genotypic data, strain 2603PH03^T is concluded to represent a novel species of the genus Verrucosispora, for which the name Verrucosispora rhizosphaerae sp. nov. is proposed. The type strain is 2603PH03^T (=CCTCC AA 2016023^T = DSM 45673^T).