CAJ | 학술논문

构建多功能淀粉酶OPMA-N和OPMA-G的分泌表达载体pMA5-OPMA-N和pMA5-OPMA-G,应用枯草杆菌表达系统实现了多功能淀粉酶 OPMA-N 与 OPMA-G 的表达与分泌,并分别对其发酵工艺进行优化.实验结果表明：OPMA-N 适宜的表达与分泌条件为：质量分数为1%的 MgSO 4、质量分数为0.3%的尿素和质量分数为0.5%的酵母粉为培养液, pH=6.5,培养液装液量为16%,37℃发酵培养48 h；OPMA-G的最适分泌表达条件为：质量分数为1%的NaCl、质量分数为1%的淀粉和质量分数为0.8%的酵母提取物为培养液, pH=7.0,培养液装液量为32%,37℃发酵培养36 h；在上述条件下,OPMA-N 和OPMA-G的分泌水平分别为发酵液中总蛋白的45%和58%,分泌酶的比活力分别为每毫克4.57和4.65酶活力单位.
구건다공능정분매OPMA-N화OPMA-G적분비표체재체pMA5-OPMA-N화pMA5-OPMA-G,응용고초간균표체계통실현료다공능정분매 OPMA-N 여 OPMA-G 적표체여분비,병분별대기발효공예진행우화.실험결과표명：OPMA-N 괄의적표체여분비조건위：질량분수위1%적 MgSO 4、질량분수위0.3%적뇨소화질량분수위0.5%적효모분위배양액, pH=6.5,배양액장액량위16%,37℃발효배양48 h；OPMA-G적최괄분비표체조건위：질량분수위1%적NaCl、질량분수위1%적정분화질량분수위0.8%적효모제취물위배양액, pH=7.0,배양액장액량위32%,37℃발효배양36 h；재상술조건하,OPMA-N 화OPMA-G적분비수평분별위발효액중총단백적45%화58%,분비매적비활력분별위매호극4.57화4.65매활력단위.
The gene encoding multifunctional amylases OPMA-N and OPMA-G were cloned into expression vector pMA5,and the secretory expression of multifunctional amylases OPMA-N and OPMA-G were achieved with the engineering strain pMA5-OPMA-N and pMA5-OPMA-G. To enhance the expression level and secretion yield of OPMA-N and OPMA-G, the fermentation conditions were further optimized.The results show that the optimal fermentation conditions for the expression and secretion of OPMA-N were obtained in the culture medium (1 6%)containing 0.5%yeast extract,0.3% urea,1% MgSO 4 ,at pH=6.5 and 37 ℃ for 48 h,and for the expression and secretion of OPMA-G was obtained in the culture medium (32%)containing 1% starch,0.8% yeast extract,1% NaCl,at pH=7.0,and 37 ℃ for 36 h.Under the optimal conditions,the secretion yields of OPMA-N and OPMA-G were about 45% and 58% of the total extracellular proteins, respectively and the specific activities of the secreted OPMA-N and OPMA-G were 4.57 and 4.65 enzymology activity unit per mg.