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

A novel bacterial strain, designated ysch24T, was isolated from a forest soil sample collected from the Cat Tien National Park, southern Vietnam. Cells were Gram-stain-negative, aerobic, gliding, filamentous or rod-shaped. The results of 16S rRNA gene analyses revealed that strain ysch24T belongs to the genus Chitinophaga, and was most closely related to Chitinophaga silvisoli GDMCC 1.1411T (97.4 %), followed by Chitinophaga oryziterrae JCM 16595T (97.3 %) and Chitinophaga sancti NBRC 15057T (96.9 %). The average nucleotide identity and digital DNA-DNA hybridization values between strain ysch24T and closely related type strains were 72.0-74.0 % and 19.1-19.4 %, respectively. Major fatty acids were iso-C15 : 0, C16 : 1 ω5c and iso-C17 : 0 3-OH and the predominant respiratory quinone was menaquinone 7. Polar lipids consisted of phosphatidylethanolamine, four unidentified aminophospholipids, two unidentified phospholipids and four unidentified lipids. The genomic DNA G+C content was 45.6 mol%. The study clearly showed that strain ysch24T should represent a novel species of the genus Chitinophaga, for which the name Chitinophaga tropicalis sp. nov. is proposed. The type strain is ysch24T (=GDMCC 1.1355T=KACC 21527T).