Question

What does it mean that restriction enzyme digestions are performed by incubating purified dna molecule with restriction enzyme at optimal condition for that specific dna

Answer 1

Dear student.

This means that an enzyme has got an optimum temperature to function properly. Enzymes are biologically active compounds which protein complex. If we increase the temperature, rate of the reaction increases but after a particular point, rate of reaction decreases sharply. As we heat above optimum temperature of enzyme, the enzyme gets denatured and stops functioning and rate of the reaction decreases sharply. The same way DNA has got melting temperature (T_m) too. So restriction enzyme digestions are performed by incubating purified DNA molecule with restriction enzyme at optimal condition for that specific DNA.

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