关键词: Taq DNA聚合酶, 制备, 优化, E. coli

Abstract: By using expression product of enzyme protein, enzyme activity and activity ratio as indexes, preparation techniques are optimized through selection of engineering bacterium lines, transformation methods, induction expression time and IPTG concentration. Total enzyme activity prepared with bacterium JM109 is higher than DH5α, transformation ratio of electric shock is higher than heat shock, and enzyme protein expression product, enzyme activity and activity ratio induced by 1.0 mmol/L IPTG for 12 h are significantly higher than other concentration and duration of IPTG induction. The results of SDS-PAGE electrophoresis and PCR amplification indicate that the enzyme product prepared with the optimized techniques meets the requirements of molecular biological experiment in purification, activity and specificity. All the indexes of the product are better than commercial enzyme products in market.

Key words: Taq DNA polymerase, preparation, optimization, E. coli