International Journal of Pharma Research 5(8):13-18

Recombinant gene expression has been the most commonly used method to obtain large quantity of proteins such as enzymes and antigens for pharmaceutical and clinical applications. Although many genes have been efficiently expressed in Escherichia coli, low level of expression and inclusion body formation are still a bottle-neck problem in desired protein production. The expression vectors pHsh and pEXC are newly developed by using elements regulating the expression of a group of genes encoding heat-shock or coldshock chaperones to overcome the low expression level and the formation of inclusion body. Thermostable enzymes are obtained using the pHsh system for applications in the biosynthesis or modification of pharmaceutical chemicals, while unstable antigens are prepared in soluble form using the T-vector of the pEXC expression system. The successful development of these new vectors offers a convenient technique for the preparation of recombinant proteins being used in enzymatic drug production, as diagnostic markers and medicinal proteins.