Expression of Taq Polymerase I Gene in Escherichia coli BL21

The thermostable properties of Taq DNA polymerase from Thermus aquaticus have contributed greatly to the yield, specificity, automation, and utility of the polymerase chain reaction method for amplifying DNA. Taq polymerase is widely used enzyme for DNA amplification in PCR techniques and highly applicable in molecular biology and biotechnology. In this study the Taq gene was amplified from the genomic DNA of the organism Thermus aquaticus and cloned into pET100 Directional TOPO ® vector. The Escherichia coli BL21 were transformed using the recombinant pET100 (8.3 Kb) containing the gene of interest and the clones of right orientation were selected and followed by protein induction. Expression of gene was observed on SDS PAGE. The band observed around 94 KDa for Taq Pol I. It is feasible, that Taq with a higher fidelity rate could be developed. The challenge is fulfillment of rising demand of Taq DNA polymerase variants that add modified nucleotides for efficient DNA amplification and labeling, this challenge can be answered by using the techniques available in protein engineering like random mutagenesis and site directed mutagenesis which will create various variants of existing Taq polymerase and screening to find out the best one which fits the above necessities.