Niabella digestorum sp. nov., a High Cell-Surface Hydrophobic Bacterium Isolated from Waste Digestion System

A high cell-surface hydrophobic bacterium, strain A18^T, was isolated from a waste digestion system in Chaozhou, China. Cells of strain A18^T were Gram-stain-positive, aerobic, non-spore-forming, non-motile, and rod-shaped. Phylogenetic analyses based on the 16S rRNA gene showed that strain A18^T shared less than 94.2% sequence similarity to all validated species in the family Chitinophagaceae, and formed a distinct lineage close to genera Niabella and Terrimonas in the neighbor-joining tree, indicating that strain A18^T is a novel species. Genome-based phylogenetic analyses revealed that strain A18^T is affiliated to the genus Niabella. The cellular components, including iso-C_15:0 and iso-C_15:1 G as the major fatty acids, menaquinone-7 as the respiratory quinone and a DNA G + C content of 40.54% supported strain A18^T as a member of the genus Niabella. However, the physiological and biochemical properties, such as enzyme activities, carbon source utilization and C_18:0 3-OH as another major fatty acids, distinguished strain A18^T from its close related species. Therefore, the name Niabella digestorum sp. nov. is proposed for this novel species. The type strain is A18^T (= GDMCC 1.3242 ^T = KCTC 92386 ^T).