Tabrizicola alkalilacus sp. nov., isolated from alkaline Lake Dajiaco on the Tibetan Plateau

Abstract

A novel Gram-stain-negative, aerobic, non-motile and rod-shaped bacterium was isolated from Lake Dajiaco on the Tibetan Plateau. Strain DJC^T grew without NaCl and tolerated up to 3 % (w/v) NaCl. Growth occurred at pH 6.0-10.0 (optimum, pH 7.0-8.0) and 15-37 °C (optimum, 25-30 °C). Vitamins were not required for growth. The main polar lipids of strain DJC^T were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant respiratory quinone was Q-10. The major fatty acid was C_{18 : 1}ω7<i>c</i>. Genome sequencing revealed a genome size of 4.61 Mbp and a G+C content of 62.9 mol%. Analysis of 16S rRNA sequences showed that strain DJC^T belonged to the genus <i>Tabrizicola</i>, with the closest neighbour <i>Tabrizicola aquatica</i> RCRI19^T (97.5 %). DNA-DNA relatedness between strain DJC^T and the closest phylogenetically related strain <i>T. aquatica</i> RCRI19^T was 40.8 %. Stain DJC^T was clearly distinguished from the type strain mentioned above through phylogenetic analysis, DNA-DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristic comparisons. Based on its phenotypic and chemotaxonomic characteristics, strain DJC^T could be classified as a representative of a novel species of the genus for which the name <i>Tabrizicola alkalilacus</i> sp. nov. is proposed. The type strain is DJC^T (=CICC 24242^T=KCTC 62173^T).