Adaptive changes in saturated fatty acids as a resistant mechanism in salt stress in Halomonas alkaliphila YHSA35

Abstract

SINCE salinity is one of the major abiotic stresses, bacteria totally have different adaptive or tolerant mechanisms that respond to salinity stress. Multiwavelength UV-Vis spectroscopy used to estimate the bacterial growth under different sodium chloride concentrations. Absorbance ratio of 280nm to 260nm (A280/A260) varied considerably according to the salt concentration. This showed some metabolic activity changes as a part of the adaptive response that allows Halomonas alkaliphila to face salinity stress changes. Here, adaptive changes of fatty-acid composition of H. alkaliphila YHSA35 because of different sodium chloride concentrations were determined. In this work, fatty acids methyl esters (FAME) composition analysis was achieved and estimated the presence of thirty-four fatty acids in H. alikaliphila YHSA35 cells. Quantitatively changes were found within the level of saturated fatty acids; Caproic, Lauric, Undecanoic, Myristic, Palmitic, Heptadecanoic and in unsaturated fatty acids; Oleic, cis-11-Eicosenoic, Erucic. In high salt concentration, unsaturated fatty acids synthesis rate is reduced, resulting in an accumulation of palmitic acid. In conclusion, levels of saturated fatty acid profile changed in H. alkaliphila YHSA35 because of salinity stress that may modulate the membrane lipid viciousness for adaptation and best cellular perform.