Construction Of Brazzein Expression System In E.coli

Sweet protein is a kind of protein which was extracted from plants in tropical rain forest located in western Africa and southern Asia since the 1970's. There is increasing interests in sweet proteins study because of their properties of being nontoxic, low-caloric, noncariogenic and it's saccharinity is thousands times than that of su-crose. Six kinds of sweet proteins have been found until now. Brazzein is the smallest one(with molecular weight 6473 Da) which was found till 1994 and has some advantageous properties such as high saccharinity(2000 times sweeter than su-crose), good thermal stability(saccharinity and electrophoresis don't change when treated at 80℃for 4h), low calorie, good water-solubility, no side effect, no change in bioactivity and sweet taste no matter what the surrounding pH is, et al. So people show great interests in Brazzein, and it becomes an ideal food additive which is especially suitable for patients suffering from diabetes, polypionia, cardiovascular diseases. Since the exploitation of Brazzein is limited by the resources and places of production and chemosynthesis is too expensive, the scale production is hard to carry out until now. So the biotechnology has become a new approach for the production of Brazzein with the development of bio-technology.In our study, Brazzein gene was reformed to Escherichia coli biased codons according to the amino acid sequence of Brazzein extracted from the fruit of Pentadiplandra Baillion, through the synthesis of five pairs of...