Nitrincola tibetensis sp. nov., isolated from Lake XuguoCo on the Tibetan Plateau

A novel Gram-stain-negative, motile and rod-shaped bacterium, designated xg18 T , was isolated from Lake XuguoCo on the Tibetan Plateau. The strain was able to grow optimally at 0-2 % NaCl and tolerate up to 6 % NaCl. Growth occurred at pH 7.0-11.0 (optimum, pH 9.0-10.0) and 15-40 °C (optimum, 37 °C). Vitamins were not required for growth. The major polar lipids of strain xg18 T were phosphatidyl ethanolamine and phosphatidylglycerol. The predominant respiratory quinone was Q-8. The major fatty acids were summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c), summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The G+C content of genomic DNA was 46.1 mol%. Analysis of 16S rRNA sequences showed that strain xg18 T belongs to the genus Nitrincola, with Nitrincola alkalisediminis MEB087 T (KC822363, 98.6 %) as its closest neighbour. The DNA-DNA relatedness value of strain xg18 T with its closest phylogenetic neighbour, N. alkalisediminis JCM 19317 T , was 43.1±3.2 %. Strain xg18 T was clearly distinguishable from the type strain of the genus Nitrincola through phylogenetic analysis, fatty acid composition data and a range of physiological and biochemical characteristics comparisons. Based on its phenotypic and chemotaxonomic characteristics, strain xg18 T could be classified as a representative of a novel species of the genus for which the name Nitrincola tibetensis sp. nov. is proposed. The type strain is xg18 T (=CICC 24457 T =KCTC 62401 T ).