Expression of Paenibacillus macerans cyclodextrin glycosyltransferase in Pichia pastoris and Bacillus subtilis
来源于软化芽孢杆菌的环糊精葡萄糖基转移酶在毕赤酵母和枯草杆菌中的表达

The cgt gene was isolated from Paenibacillus macerans by PCR amplification and was inserted into vectors of pPIC9K and pMA5. The recombinant vectors were transformed to Pichia pastoris KM71 and Bacillus subtilis WB600, respectively. The results showed that a-CGTase activity in the culture media of recombinant P. pastoris was only 0.2 U/mL, while it was 1.9 U/mL in recombinant B. subtilis. In addition, we optimized the culture conditions of the recombinant B. subtilis strain. After cultivation at 37oC for 24 h with shake flask, the CGTase forming activity in culture media reached to 4.5 U/mL (hydrolysis activity was 3200 IU/mL), which is 9.8-fold to that of the original strain P. macerans.