Mongoliicoccus alkaliphilus sp. nov. and Litoribacter alkaliphilus sp. nov., isolated from salt pans

Abstract

Four bacterial strains (JC165T, JC166T, JC169 and JC170) were isolated from salt pan soils from a coastal region of Tamilnadu, India. They were obligately aerobic, pink- to red-pigmented, mesophilic, haloalkaliphiles having chemoorganoheterotrophic growth on various carbon sources and were catalase- and oxidase-positive. Phototrophic growth and bacteriochlorophyll a were absent in all four strains. Major carotenoids present were β-carotene and rhodoxanthin. The main fatty acid in all strains was iso-C15 : 0. The main polar lipids were phosphatidylethanolamine (PE) and phosphatidylcholine (PC) as well as a few unidentified lipids. Bacterial hopane derivatives and diplopterol (DPL) were detected in all four strains. Based on the 16S rRNA gene sequences, all four strains belong to the family Cyclobacteriaceae in the phylum Bacteroidetes . Strains JC165T and JC169 had a sequence similarity of 97.2 % with Mongoliicoccus roseus MIM28T, while strains JC166T and JC170 had a sequence similarity of 99.5 % with Litoribacter ruber YIM CH208T. Strains JC165T/JC169 and JC166T/JC170 had genomic DNA reassociation values (based on DNA–DNA hybridization) of 21±2 % and 23±1 % with M. roseus KCTC 19808T ( = MIM28T) and L. ruber KCTC 22899T ( = YIM CH208T), respectively, suggesting that they represented novel species. The reassociation values of >85 % between strains JC165T and JC169, and JC166T and JC170 suggested they were strains of the same species. The genomic information was supported by phenotypic observations leading to the proposal of two novel species, Mongoliicoccus alkaliphilus sp. nov. (type strain, JC165T = KCTC 32210T = LMG 27255T) and Litoribacter alkaliphilus sp. nov. (type strain, JC166T = KCTC 32217T = LMG 27256T).