INFLUENCE OF THE CHANGE OF OTSAB PATHWAY ON THE INTRACELLULAR TREHALOSE CONTENT AND CELLULAR TOLERANCE OF CORYNEBACTERIUM GLUTAMICUM ATCC 13032

The OtsAB pathway is the most important pathway of the three pathways for intracellular trehalose biosynthesis in Corynebacterium glutamicum.An OtsAB pathway defective mutant Corynebacterium glutamicum ΔotsAB was constructed from wild-type Corynebacterium glutamicum ATCC 13032 by SOE-PCR and homologous recombination;and OtsA and OtsB genes over-expressing strain were constructed by using Corynebacterium glutamicum-E.Coli shuttle expression vector pECXK99E at the same time.The intracellular trehalose contents of these two mutants and wild-type strain cultured under different osmotic pressures and at different cultivation temperatures were measured,and the tolerance of these strains to osmotic pressure and temperature was researched.The results showed that the defect and over-expression of the OtsAB pathway greatly changed the intracellular trehalose content of Corynebacterium glutamicum,which then might influence the tolerances of cells to osmotic pressure and temperature.