Cloning of phosphomannomutase/phosphoglucomutase (pmm/pgm) gene of Vibrio anguillarum related to synthesis of LPS and construction of knock out mutant

Abstract

We sequenced 1341bp ORF of phosphomannomutase/phosphoglucomutase (pmm/pgm) gene from Vibrio anguillarum, the causative agent of fish vibriosis catalyzes the interconversion of mannose 1- phosphate and mannose 6- phosphate, and glucose 1- phosphate and glucose 6- phosphate. We found that pmm/pgm gene was up regulated under cold stress by Reverse Trancriptase-Polymerase Chain Reaction (RT-PCR). We constructed knock out mutant by homologous recombination to identify relation between PMM/PGM protein and synthesis of lipopolysaccharide (LPS). LPS from V. anguillarum wild type and mutant was isolated. We checked high molecular weight (HMW) of LPS was immigrated and several bands smeared by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and silver staining. Growth and viability of mutant was lower than V. anguillarum wild type on stationary phase. In this study, we identified pmm/pgm gene has a important role for biosynthesis of LPS.