Polyhydroxyalkanoates produced by Halomonas gomseomensis, an extreme halophilic bacterium, from different carbon sources

Abstract

Abstract Genotypic and phenotypic characterization was performed on the JCCOL25.2 strain, isolated from hypersaline ponds located at Las Coloradas (Yucatan, Mexico). Accumulation of polyhydroxyalkanoates (PHAs) in response to different carbon sources was evaluated. Characterization was carried out on the JCCOL25.2 strain of Halophilic Microorganism Library obtained from water samples from “Las Coloradas” saline ponds. PHA accumulation was determined by Nile red staining. Sequence analysis of the JCCOL25.2 16S rRNA gene revealed 99.9% identity with Halomonas gomseomensis. This bacterium exhibited PHA accumulation in broths containing sodium acetate, starch, sodium citrate, glucose, fructose, soybean oil, glycerol, or saccharose as a carbon source. Polyhydroxyalkanoates were purified and characterized by FTIR, DSC, and TGA, showing that poly(3-hydroxybutyrate) was obtained in all treatments. Glycerol was the carbon source that gave the highest yield during PHA production in H. gomseomensis. The carbon source did not affect the chemical structure of the polymer biosynthesized by this bacterium. Although H. gomseomensis strains have been isolated from saline water in many countries to our knowledge, there are no reports on the biosynthesis of PHA’s from this species.