Niastella populi sp. nov., isolated from soil of Euphrates poplar (Populus euphratica) forest, and emended description of the genus Niastella

Abstract

A novel bacterial strain, designated THYL-44T, was isolated from the soil of a Euphrates poplar (Populus euphratica) forest in Xinjiang, China. The cells were strictly aerobic, Gram-staining-negative, non-flagellated, non-motile and filamentous. Growth occurred at 17–37 °C (optimum 30 °C), at pH 5.0–8.0 (optimum pH 7.0) and with 0–1 % NaCl (w/v; optimum 0 %). Flexirubin pigments were not produced. A phylogenetic analysis based on 16S rRNA gene sequences revealed that strain THYL-44T was closely related to Niastella koreensis KACC 11465T (95.5 % sequence similarity). The major respiratory quinone was MK-7 and the predominant cellular fatty acids were iso-C15 : 0 (28.6 %), iso-C17 : 0 3-OH (23.9 %) and iso-C15 : 1 G (17.4 %). The DNA G+C content was 45.2 mol%. Therefore, the phylogenetic, physiological and chemotaxonomic data demonstrated that strain THYL-44T represents a novel species of the genus Niastella, for which the name Niastella populi sp. nov. is proposed. The type strain is THYL-44T (=CCTCC AB 208238T=KCTC 22560T). On the basis of new data, an emended description of the genus Niastella is also proposed.