Flavobacterium tibetense sp. nov., isolated from a wetland.

Abstract

A novel, Gram-stain-negative, non-motile and rod-shaped bacterium, designated YH5T, was isolated from the YonghuCo wetland on the Tibetan Plateau. The strain was able to grow optimally with 1 % (w/v) NaCl and tolerated up to 3 % NaCl. Growth occurred at pH 6-9 (optimum pH 7) and 10-37 °C (optimum 30 °C). Vitamins were not required for growth. The major polar lipid of strain YH5T was phosphatidylethanolamine. The predominant respiratory quinone was menaquinone 6 (MK-6). The major fatty acids were iso-C15 : 0, C16 : 0 10-methyl and/or iso-C17 : 1ω9c, iso-C17 : 0 3-OH, iso-C15 : 1 G and iso-C15 : 0 3-OH. Genome sequencing revealed a genome size of 2.74 Mbp and a G+C content of 33.3 mol%. Analysis of 16S rRNA gene sequences showed that strain YH5T belonged to the genus Flavobacterium, with the closest neighbours Flavobacterium luticocti xz20T (96.7 % similarity), Flavobacterium jejuense EC11T (96.4 %), Flavobacterium jumunjinense HME7102T (95.9 %) and Flavobacterium dongtanense LW30T (95.6 %). DNA-DNA relatedness between strain YH5T and the closest phylogenetically related strain F. luticocti xz20T was 27.0 %. Strain YH5T was clearly distinguished from the reference type strains based on phylogenetic analysis, DNA-DNA hybridization, fatty acid composition and a range of physiological and biochemical characteristics. Based on its phenotypic and chemotaxonomic characteristics, strain YH5T is classified as a representative of a novel species of the genus Flavobacterium, for which the name Flavobacterium tibetense sp. nov. is proposed. The type strain is YH5T (=CICC 24247T=KCTC 62174T).