Taq polymerase is an enzyme isolated from the bacterium- Thermus aquaticus. Its main use is in PCR reactions where its resistance to damage from high temperatures is essential. Taq polymerase's thermostable properties allow it to undergo multiple rounds of the PCR reaction cycle without being damaged by the high temperatures required to amplify the DNA.
During PCR, Taq pol is used to extend the primers attached to the single stranded DNA and therefore create new pieces of DNA complementary to the original sample. This step is repeated 30 times at a temperature of 72 degrees to produce an amplified sample of the DNA which at its increased volume, is ideal for DNA sequencing.