Metabolic engineering Corynebacterium glutamicum for D-chiro-inositol production

AbstractD-chiro-inositol (DCI) is a potential drug for the treatment of type II diabetes and polycystic ovary syndrome. In order to effectively synthesize DCI inCorynebacterium glutamicum, the genes related to inositol catabolism in clustersiol1 andiol2 were knocked out inC. glutamicum SN01 to generate the chassis strain DCI-1. DCI-1 did not grow in and catabolizemyo-inositol (MI). Subsequently, different exogenous and endogenous inosose isomerases were expressed in DCI-1 and their conversion ability of DCI from MI were compared. After fermentation, the strain DCI-7 co-expressing inosose isomerase IolI2 and inositol dehydrogenase IolG was identified as the optimal strain. Its DCI titer reached 3.21  g/L in the presence of 20 g/L MI. On this basis, the pH, temperature and MI concentration during whole-cell conversion of DCI by strain DCI-7 were optimized. Finally, the optimal condition that achieved the highest DCI titer of 6.96 g/L were obtained at pH 8.0, 37 °C and addition of 40 g/L MI . To our knowledge, it is the highest DCI titer ever reported.
Source: World Journal of Microbiology and Biotechnology - Category: Microbiology Source Type: research