Question

The thermostable enzymes 'Taq' and 'Pfu' isolated from thermophilic bacteria are :

• A. Restriction endonucleases
• B. DNA ligases
• C. DNA polymerases
• D. RNA polymerase

Answer 1

The correct option is C DNA polymerases

DNA polymerase

• DNA polymerases are the enzymes that can add deoxyribonucleotides to an already existing DNA strand or primer.
• Hence DNA polymerases are used for in vitro DNA synthesis.
• The thermostable property of thermostable DNA polymerases makes it possible for them to remain active during the high temperature conditions of PCR, especially during the denaturation of double stranded DNA.
• Examples of such thermostable DNA polymerases include ‘Taq and Pfu’ isolated from thermophilic bacteria.