Methylophaga lonarensis sp. nov., a novel moderately haloalkaliphilic methylotroph isolated from the soda lake sediments of a meteorite impact crater

A novel moderately haloalkaliphilic methylotrophic bacterium (strain MPL(T)), possessing the ribulose monophosphate pathway for carbon assimilation, was isolated from two week old Lonar Lake sediment microcosms that were actively oxidizing methane. The isolate, which utilizes methanol, is an aerobic, Gram-negative, asporogenous, motile short rod that multiplies by binary fission. It requires NaHCO(3) or NaCl for growth and although not auxotrophic for vitamin B12, the addition of vitamin B12 enhances its growth. Optimal growth occurs with 0.5-2% (w/v) NaCl at 28-30 °C and pH 9.0-10.0. The cellular fatty acid profile of the strain consists primarily of straight-chain saturated C(16:0) and unsaturated C(16:1)?7c and C(18:1)?7c acids. The major ubiquinone is Q-8. The dominant phospholipids are phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Cells accumulate the cyclic imino acid ectoine as the main compatible solute. The DNA G+C content is 50.0 mol%. Based on 16S rRNA gene sequence similarity (94.0-95.4 %) with the type strains of methylotrophs belonging to the genus Methylophaga and DNA-DNA relatedness (31%) with the closest described species Methylophaga alcalica M39(T), it is proposed that isolate MPL(T) represents a novel species, Methylophaga lonarensis sp. nov. (type strain MPL(T) =VKM B-2684(T) =MCC 1002(T)).