Abstract:

Objective: To induce the expression of recombinant glycosidase using D-lactitol instead of isopropyl-β-Dthiogalactoside
(IPTG). Methods: Single-factor experiments were performed to discuss the effect of D-lactitol concentration,
induction time and temperature on the expression of recombinant glucosidase and consequently select three appropriate
levels for each of the three variables. Subsequently, the levels of these variables were optimized by regression analysis and
response surface methodology. Results: The optimal induction conditions were determined to be induction at 34 ℃ for
7.0 h with 1.0 mmol/L lactitol. Conclusion: D-Lactitol can replace IPTG as an ideal inducer for the production of
recombinant proteins in genetically engineered strains with the efficient promoter of lac and its derivatives.

Key words: α-glucosidase, induction, response surface methodology, D-lactitol