Chitinophaga solisilvae sp. nov., isolated from forest soil.

Abstract

A Gram-stain-negative, strictly aerobic, non-motile and rod-shaped bacterial strain, O9T, was isolated from a forest soil sample collected at Dai, Xishuangbanna, Yunnan Province, PR China. Strain O9T grew optimally at pH 7.0, at 28‒30 °C and in the absence of NaCl. 16S rRNA gene sequence analysis placed strain O9T within the genus Chitinophaga of the family Chitinophagaceae, with Chitinophaga terrae KP01T (97.8 %), Chitinophaga jiangningensis JN53T (97.7 %), Chitinophaga niastensis JS16-4T (97.4 %), Chitinophaga qingshengii JN246T (97.3 %) and Chitinophaga dinghuensis DHOC24T (97.3 %) as its closest relatives. Strain O9T hydrolysed casein, gelatin and Tween 80. It could not assimilate l-arabinose, l-rhamnose, sucrose, melibiose, gentiobiose or d-fructose as a carbon source. It was negative for esterase lipase (C8) and β-glucosidase. Phosphatidylethanolamine was the predominant polar lipid. The major respiratory quinone of strain O9T was MK-7. Its major fatty acids were iso-C15:0 (34.2 %), C16:1 ω5c (20.9 %) and iso-C17:0 3-OH (12.6 %). The genomic DNA G+C content of strain O9T was 49.0 mol% based on total genome calculations. The average nucleotide identity score between the genomic sequence of strain O9T and that of Chitinophaga terrae KP01T was 72.9%. The Genome-to-Genome Distance Calculator showed that DNA‒DNA hybridization values for strain O9T and Chitinophaga terrae KP01T were 13.6, 21.1 and 14.4%, respectively. Based on the polyphasic taxonomic data, strain O9T represents a novel species of the genus Chitinophaga, for which the name Chitinophaga solisilvae sp. nov. is proposed. The type strain is O9T (=CGMCC 1.12462T=KCTC 32404T).