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(T), was isolated from oil-contaminated soil. Strain Ktm-2(T) was able to grow at 15 to 40 degrees 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(T) represented a member of the genus Chitinophaga and shared highest sequence similarity with Chitinophaga barathri YLT18(T) (98.1 %), Chitinophaga cymbidii R156-2(T) (96.4 %) and Chitinophaga niabensis JS13-10(T) (96.3 %). The only respiratory quinone was menaqunone-7, the major polar lipid was phosphatidylethanolamine and the predominant fatty acids were iso-C-15:0, C-16:1 omega 5c and iso-C-17:0 3-OH. The DNA G+C content was 52.1 mol%. The DNA-DNA relatedness between strain Ktm-2(T) and C. barathri YLT18(T) 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(T) represents a novel species of the genus Chitinophaga, for which the name Chitinophaga humicola sp. nov. is proposed. The type strain is Ktm-2(T) (=KEMB 9005-693(T)=KACC 19388(T)=JCM 32158(T)).