Question

What is Taq Polymerase and why should it be used?

Answer 1

Taq polymerase is a thermostable DNA polymerase and it is isolated from thermophilic bacterium Thermus aquaticus. It is mainly used in polymerase chain reaction in amplifying short DNA segments. Taq DNA polymerase is extremely accurate, depending on reaction conditions it only makes a mistake once in approximately 100,000 nucleotide insertions. Taq executes best results when amplifying DNA fragments is less than 2 kb, but works on fragments up to 3–4 kb. Within this limit Taq is robust and easily optimized but as the amplifying DNA size increase above the limit it loses its effectiveness. During the amplification reaction Taq polymerase will add wrong base at particular rate leading to mismatch information, this is called as error rate. Taq polymerase would stall at these mismatchd and more of such mismatched will inhibit the amplification process. We can prevent this by adding small amount of proof reading enzyme and with this mixture amplification of 20Kb fragment can be achieved.