Question

Which of the following statements is correct with respect to a unit of an enzyme?

(a) One unit of enzyme is defined as the amount of enzyme required to digest 1miligram of standard DNA in a specific time of 1hr and under given temperature conditions

(b) The amount of enzyme required doesn’t vary with the number of sites present in the DNA

(c) If more number of sites is there in the DNA more units of enzyme are required in comparison to same amount of DNA with fewer sites

(d) The amount of enzyme required for digestion of DNA with less number of sites is more than that of more number of sites in the same amount of DNA

This question was addressed to me in an online interview.

This intriguing question comes from Restriction Endonuclease & Phosphatases topic in portion Basics of Genetic Engineering of Genetic Engineering

Answer 1

The correct answer is (c) If more number of sites is there in the DNA more units of enzyme are required in comparison to same amount of DNA with fewer sites

To explain: One unit of enzyme is the quantity required for digestion of 1 microgram of DNA in 1hr and under given temperature conditions. The amount of enzyme required is more if more number of sites is there in the same amount of DNA in comparison to less number of sites.