What is the enzyme that synthesized DNA used in PCR that distinguishes it from the equivalent enzyme that carry out the same function in our cells or those of most bacteria?

PCR uses Taq polymerase (a type of DNA polymerase that comes from the thermophilic bacterium, Thermus aquaticus).The difference between that version of the enzyme and the one that our cells use is that Taq polymerase functions at much higher temperatures, allowing it to withstand PCR temperatures for thermal cycling.