DNA polymerase obtained from bacterium Thermus aquaticus is used in PCR because (A) it can easily make 1 billion copies of DNA in PCR (B) it remains active at denaturation temperature (C) it can easily ligate with primer (D) all of these
Option B. The final step of PCR is the extension, wherein Taq DNA polymerase (isolated from a thermophilic bacterium Thermus aquaticus) synthesizes the DNA region between the primers, using dNTPs (deoxynucleoside triphosphates) and Mg2+. The primers are extended towards each other so that the DNA segment lying between the two primers is copied. The optimum temperature for this polymerisation step is 72oC. Taq polymerase remains active during high temperature-induced denaturation of double-stranded DNA.
