Chitinophaga ginsengihumi sp nov., isolated from soil of ginseng rhizosphere

A novel strain designated SR18(T) was isolated from the rhizosphere soil of a ginseng in Korea. Cells were Gram-staining-negative, motile by gliding, catalase-positive and oxidase-negative, non-spore-forming rods. The isolate grew aerobically at 15-45 degrees C (optimum 28 degrees C), pH 5.5-7.5 (optimum pH 7.0) and with 0-3.0% (w/v) NaCl (optimum 1.5% NaCl). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain SR18T belongs to the genus Chitinophaga with sequence similarity of 97.2% and 97.0% to Chitinophaga japonensis 758(T) and Chitinophaga rupis CS5-B1(T), respectively. Similarity to other: species of the genus Chitinophaga was 92.8-95.5 %. The predominant menaquinone was MK-7. Major fatty acids were iso-C-15:0 and C-16:1 omega 5c. The polar lipids included phosphatidylethanolamine, unidentified phospholipids, unknown aminolipids and unknown lipids. The genomic DNA G+C content was 45.3 mol%. DNA-DNA relatedness between strain SR18(T) and C. japonensis NBRC 16041(T) was 29-32%. On the basis of polyphasic analysis from this study, strain SR18(T) represents a novel species of the genus Chitinophaga, for which the name Chitinophaga ginsengihumi sp. nov. is proposed. The type strain is SR18(T) (=KACC 17604(T)=NBRC 109832(T)).