Chitinophaga humicola sp. nov., isolated from oil-contaminated soil.

A yellow-coloured, Gram-stain-negative, non-motile, aerobic and rod-shaped bacterium, designated strain Ktm-2, was isolated from oil-contaminated soil. Strain Ktm-2 was able to grow at 15 to 40 °C, pH 4.5-10.0 and 0-2 % (w/v) NaCl concentration. This strain was taxonomically characterized by a polyphasic approach. Based on the 16S rRNA gene sequence analysis, strain Ktm-2 represented a member of the genus Chitinophaga and shared highest sequence similarity with Chitinophaga barathri YLT18 (98.1 %), Chitinophaga cymbidii R156-2 (96.4 %) and Chitinophaga niabensis JS13-10 (96.3 %). The only respiratory quinone was menaqunone-7, the major polar lipid was phosphatidylethanolamine and the predominant fatty acids were iso-C15 : 0, C16 : 1ω5c and iso-C17 : 0 3-OH. The DNA G+C content was 52.1 mol%. The DNA-DNA relatedness between strain Ktm-2 and C. barathri YLT18 was 22.0 %, which falls below the threshold value of 70 % for the strain to be considered a novel species. The morphological, physiological, chemotaxonomic and phylogenetic analyses clearly distinguished this strain from its closest phylogenetic neighbours. Thus, strain Ktm-2 represents a novel species of the genus Chitinophaga, for which the name Chitinophagahumicola sp. nov. is proposed. The type strain is Ktm-2 (=KEMB 9005-693=KACC 19388=JCM 32158).