Chitinophaga varians sp nov., isolated from forest soil

A Gram-stain-negative, aerobic, non-motile bacterium, designated strain 10-7W-9003(T), was isolated from the forest soil of Limushan National Forest Park, south-east China (19 degrees 10' 42 '' N, 109 degrees 44' 45 '' E). Strain 10-7W-9003(T)showed a shape change during the course of culture from long filamentous cells (5-10x0.4-0.5 mu m) at 5-36 h, to rod shaped (1.0-1.5x0.5-0.7 mu m) with inoculation after 2 days. It grew optimally at 28-30 degrees C and pH 6.5-7.5. On the basis of 16S rRNA gene sequence analysis, it belongs to the genus Chitinophaga and is most closely related to Chitinophaga eiseniae KACC 13774(T)and Chitinophaga qingshengii JCM 30026(T), with 16S rRNA gene sequences similarities of 98.8 and 98.3 %, respectively. However, the DNA-DNA hybridization study showed that strain 10-7W-9003(T)shared relatively low relatedness values with KACC 13774(T)(21.8 %) and JCM 30026(T)(20.4 %), respectively. The major fatty acids (>10 %) were iso-C-15 : 0, C-16 : 1 omega 5c and iso-C-17 (:) (0) 3-OH. The genomic DNA G+C content was 50.7 mol%. It contained MK-7 as the major quinone. The phenotypic, chemotaxonomic and phylogenetic data clearly showed that strain 10-7W-9003(T)represents a novel species of the genus Chitinophaga, for which the name Chitinophaga varians sp. nov. is proposed. The type strain is 10-7W-9003(T)(=GDMCC 1.1252(T)=KACC 19415(T)=KCTC 52926(T)).