Paracoccus salsus sp. nov., a novel slightly halophilic bacterium isolated from saline lake sediment.

Abstract

A Gram-stain-negative, non-motile, slightly halophilic and non-endospore-forming alphaproteobacterium, designated strain EGI L200073T, was isolated from saline lake sediment sampled in Xinjiang Uygur Autonomous Region, China. The taxonomic position of the isolate was determined using the polyphasic taxonomic analysis and phylogenomic analysis. Phylogenetic analysis based on 16S rRNA gene sequence similarities indicated that strain EGI L200073T formed a distinct clade with Paracoccus seriniphilus DSM 14827T and shared sequence identity of 98.56 %. The novel isolate could be distinguished from other species of the genus Paracoccus by its distinct phenotypic, physiological and genotypic characteristics. Optimal growth of strain EGI L200073T occurred on marine agar 2216 at pH 8.0 and 30 °C. The major respiratory quinone was Q-10, while the major fatty acids (>10%) were summed feature 8 (C17 : 1 ω6c and/or C17 : 1 ω7c) and C18 : 0. The detected polar lipids included diphosphatidylglycerol, phosphatidylcholine and phosphatidylglycerol. Based on the genome sequence of strain EGI L200073T, the G+C content of the novel isolate was 65.7 mol%. The average nucleotide identity, amino acid identity and digital DNA-DNA hybridization values of strain EGI L200073T against related members in the genus Paracoccus were below the cut-off points proposed for delineation of a novel species. According our polyphasic taxonomic data, strain EGI L200073T represents a new species of the genus Paracoccus, for which the name Paracoccus salsus sp. nov. is proposed. The type strain of the proposed novel isolate is EGI L200073T (=KCTC 92045T=CGMCC 1.19242T).