Taq Polymerase (EC 2.7.7.7): With Particular Emphasis on Its Use in PCR Protocols

Taq polymerase (EC 2.7.7.7) is a thermostable DNA-dependent DNA polymerase that was first isolated in 1976 from Thermus aquaticus strain YT-1 (ATTC # 25 104)( 1 ). It catalyzes the template-directed polymerization of dNTPs at high temperatures. When Taq polymerase was isolated in 1976, nobody could have known the impact the application of Taq polymerase to the polymerase chain reaction (PCR) would have on molecular biology ( 2 , 3 ). In an issue of Science in 1989, the enzyme was dubbed molecule of the year ( 4 ).