Why is Taq polymerase used more commonly in PCR than DNA polymerase I from E.coli?
1)Taq polymerase remains active during the high heat denaturation step unlike DNA polymerase I
2)Taq polymerase is less expensive than DNA polymerase I
3)Taq polymerase must be added after each deanturation step unlike DNA polymerase I
A) 1
B) 2
C) 3
D) 1 and 2
E) All of these

Question

Quizplus · Accepted Answer

Taq polymerase is derived from Thermus aquaticus, a bacterium that lives in hot environments, making it stable and active at the high temperatures used in PCR for denaturing DNA. DNA polymerase I from E.coli, on the other hand, denatures at these high temperatures and would need to be replenished after each cycle, making Taq polymerase more suitable for PCR.

Why Is Taq Polymerase Used More Commonly in PCR Than