Construction Fermentation of Engineered Strain and Properties of Recombinant ?-glutamyltranspeptidase / 中国生物工程杂志

The ?glutamyltranspeptidase encoding gene(ggt) from Bacillus subtilis SYU 20016 was amplified by PCR. The ggt gene was inserted in pBV220 to yield the recombinant expression vector pBV220ggt. Overexpression of ggt in E.coli JM109 was achieved with pBV220ggt. SDSPAGE analysis showed an overexpressed recombinant product at about 65kDa,consistent with the molecular weight predicted from gene sequence. The ferment conditions of r-glutamyltranspeptidase were also discussed. The optimum temperature and pH for the enzyme were determined as 30℃ and 7.2 respectively.The cultures were incubated at 42℃ for 4h with broth volume 20ml/250ml flask and the yield of 6U/ml was obtained, enzyme activity of B. subtilis NX2 was only 3.2 U/ml.