Abstract
Aim. The Tag DNA polymerase is the most commonly used enzyme in modern biotechnology. Being thermostable and capability to polymerize the DNA, this enzyme has been extensively used in PCR, DNA sequencing etc. To cope with the high demand of Taq, recombinant Taq is being produced. The yield and activity of Taq polymerase is determined by many parameters. These include IPTG concentration, IPTG induction period and IPTG and incubation temperature. The current study was to analyze Tag polymerase produced in pTTQ18 Vector as well as to optimize its expression and purification.
Methods. The E. coli strain DH5 alpha was transformed with pTTQ18 vector carrying the Tag polymerase gene.
Results. Maximum expression of Taq polymerase gene was observed at IPTG concentration of 200 mu M with induction period of 12 h. In order to optimize purification, the cellular lysate was best incubated at 75 degrees C. The activity of purified Taq polymerase was also calculated by comparing it with commercial Taq and was found 1 unit/mu l while that of commercial Taq was 5 U/mu L.
Conclusion. Overall, results conclude that, at optimum conditions, DH5 alpha transformed with pTTQ18 produce efficient level of Taq polymerase that can be use commercially.