Phytoactinopolyspora endophytica gen. nov., sp. nov., a halotolerant filamentous actinomycete isolated from the roots of Glycyrrhiza uralensis F.

A novel endophytic actinomycete, designated strain EGI 60009T, was isolated from the roots of Glycyrrhiza uralensis F. collected from Xinjiang Province, north-west China. The isolate was able to grow in the presence of 0-9% (w/v) NaCl. Strain EGI 60009T had particular morphological properties: the substrate mycelia fragmented into rod-like elements and aerial mycelia differentiated into short spore chains. ll-2, 6-Diaminopimelic acid was the cell-wall diamino acid and rhamnose, galactose and glucose were the cell-wall sugars. MK-9(H4) was the predominant menaquinone. The major fatty acids of strain EGI 60009T were iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 0, iso-C17 : 0, iso-C17 : 1 and I/anteiso-C17 : 0 B. Mycolic acids were absent. The DNA G+C content of strain EGI 60009T was 70.4 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain EGI 60009T belongs to the family Jiangellaceae and formed a distinct clade in the phylogenetic tree. 16S rRNA gene sequence similarities between strain EGI 60009T and other members of the genera Jiangella and Haloactinopolyspora were 96.1-96.4 and 95.7-96.0%, respectively. Based on these results and supported by morphological, physiological and chemotaxonomic data and numerous phenotypic differences, a novel species of a new genus, Phytoactinopolyspora endophytica gen. nov., sp. nov., is proposed. The type strain of Phytoactinopolyspora endophytica is EGI 60009T ( = KCTC 29657T = CPCC204078T).