Cohaesibacter haloalkalitolerans sp. nov., isolated from a soda lake, and emended description of the genus Cohaesibacter

Abstract

Two novel Gram-stain-negative, motile, catalase-negative and oxidase-positive strains of bacteria (JC131T and JC112) were isolated from Lonar, a soda lake in India. Based on 16S rRNA gene sequence similarity studies, strains JC131T and JC112 belong to the family Cohaesibacteraceae of the class Alphaproteobacteria and were most closely related to Cohaesibacter marisflavi DQHS21T (98.0 %) and Cohaesibacter gelatinilyticus CL-GR15T (96.0 %). Polar lipids of strains JC131T and JC112 include phosphatidylglycerol, phosphatidylethnolamine, phosphatidylmonomethylethanolamine, diphosphatidylglycerol and two unidentified lipids (L1 and L2). Both strains have diplopterol, diploptene, an unidentified hopane (UH) and bacteriohopane derivatives (BHD1 and 2) as major hopanoids and an unidentified pigment (P1). The predominant isoprenoid quinone of both strains was ubiquinone-10 (Q10). Whole-cell fatty acid analysis of both strains revealed that C18 : 1ω7c was the predominant cellular fatty acid and significant proportions of C16 : 0, summed feature 3 (C16 : 1ω7c and/or iso-C15 : 0 2-OH), 11-methyl C18 : 1ω7c, C18 : 1ω9c, C18 : 0 and C20 : 1ω7c were also detected. The DNA G+C content of strains JC131T and JC112 was 54.6 and 53.8 mol%, respectively. The genome reassociation (based on DNA–DNA hybridization) of strains JC131T and JC112 with Cohaesibacter marisflavi NCCB 100300T ( = DQHS21T) was about 58 %, while between JC131T and JC112 it was about 87 %. On the basis of physiological, biochemical and chemotaxonomical properties, strains JC131T and JC112 are differentiated from the other two members of the genus Cohaesibacter . Strains JC131T and JC112 represent a novel species of the genus Cohaesibacter , for which the name Cohaesibacter haloalkalitolerans sp. nov. is proposed. The type strain is JC131T ( = KCTC 32038T = NBRC 109022T). An emended description of the genus Cohaesibacter is presented.