A Gram-negative, non-motile, facultatively anaerobic, rod-shaped bacterium, designated strain RS1-74T, was isolated from the surface water of Sayram Lake, Xinjiang Uygur Autonomous Region, China. The strain was able to grow optimally at 30 °C and pH 7.0-7.5, and in the presence of 0-0.5 % (v/w) NaCl. Catalase and oxidase activities were present. H2S was produced. Chemotaxonomic analysis showed Q-10 was the sole respiratory quinone. The polar lipids were composed of phosphatidylethanolamine, diphosphatidylglycerol, two glycolipids, phosphatidylglycerol, sphingoglycolipid and two unidentified lipids. Summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) were the predominant fatty acids. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain RS1-74T was closely related to 'Sandaracinobacter neustonicus' JCM 30 734 (98.65 %), 'Sandaracinobacter sibiricus' RB16-17 (98.42 %) and Sandaracinobacteroides hominis SZY PN-1T (97.09%). The genomic DNA G+C content was 66.45 mol%. The average nucleotide identity and DNA-DNA hybridization values among the genomes of strain RS1-74T and 'Sandaracinobacter neustonicus' JCM 30734 and Sandaracinobacteroides hominis SZY PN-1T were 78.2 and 77.22 %, and 22.2 and 20.40 %, respectively. Based on the physiological, biochemical, phylogenetic and genomic data, strain RS1-74T represents a novel species within the genus Sandaracinobacteroides, for which the name Sandaracinobacteroides sayramensis sp. nov. is proposed, with type strain RS1-74T (=KCTC 82674T=MCCC 1K06282T).
Keywords: Alphaproteobacteria; Sandaracinobacteroides; Sayram lake; phylogenetic analysis; whole genome sequencing.