Optimization of culture medium and fermentation conditions of transglutaminase by recombinant Escherichia coli

In order to obtain high yield of the transglutaminase protein,fermentation and induction conditions for recombinant E.coli Rosetta DE3 were optimized in shake-flasks.The optimal composition of the culture medium were as followed: glucose 4.0g/L,yeast extract 3.0g/L,NH4Cl 4.0g/L,Na2HPO4 2.0g/L,K2HPO4 1.0g/L,MgSO4·7H2O 1.0g/L and NaCl 3.0g/L.The optimal fermentation conditions were as followed: medium volume 25mL in 250mL shake-flask,inoculum 5%(v/v),IPTG 0.6mmol/L and induction duration 4h.