Longispora urticae sp. nov., isolated from rhizosphere soil of Urtica urens L., and emended descriptions of the species Longisporaalbida and Longisporafulva

Two Gram-stain-positive, aerobic actinomycete strains, designated NEAU-PCY-3 and NEAU-PCY-4, were isolated from rhizosphere soil of Urtica urens L. collected from Anshan, Liaoning Province, northeast PR China. The 16S rRNA gene sequence analysis showed that the two strains exhibited 99.9 % 16S rRNA gene sequence similarity with each other and that they were most closely to Longispora fulva DSM 45356 (98.7, 98.9 %) and Longispora albida JCM 11711 (97.1, 97.2 %). Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the two strains were located in the same lineage and formed a cluster with the genus Longispora. Both strains were observed to contain MK-10(H4) and MK-10(H6) as the predominant menaquinones. The cell wall peptidoglycan was found to contain meso-diaminopimelic acid, d-glutamic acid, glycine and l-alanine. Whole-cell hydrolysates mainly contained galactose, ribose and xylose. The phospholipid profile contained diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol, several glycolipids and several unknown lipids. The major cellular fatty acids for strain NEAU-PCY-3 were iso-C16 : 0, iso-C17 : 0, anteiso-C17 : 0 and C18 : 1ω5c. The DNA-DNA hybridization value between strains NEAU-PCY-3 and NEAU-PCY-4 was 83.6±0.4 %, and the values between the two strains and their closest phylogenetic relatives, belonging to the genus Longispora, were well below 70 %, supporting that they represented a distinct genomic species. An array of phenotypic characteristics also differentiated the strains from their closely related species, the only two validly published Longispora species. On the basis of the genetic, chemotaxonomic and phenotypic properties, strains NEAU-PCY-3 and NEAU-PCY-4 were classified as representatives of a novel species of the genus Longispora, for which the name Longispora urticae sp. nov. is proposed. The type strain is NEAU-PCY-3 (=DSM 105119 =CCTCC AA 2017017 ).