Question

Bal31 is also an enzyme which is used. Which of the following statements hold true in its context?

(a) It is having only 3’-5’ exonuclease activity and no endonuclease activity

(b) It is having only an endonuclease activity

(c) It is having 5’-3’ exonuclease activity

(d) It leads to shortening from both the ends

The question was asked in unit test.

This intriguing question comes from Exonucleases in division Basics of Genetic Engineering of Genetic Engineering

Answer 1

Right option is (d) It leads to shortening from both the ends

For explanation: Bal31 is having an exonuclease activity in 3’-5’ direction and also an endonuclease activity. Thus, after having 3’-5’ exonuclease activity, the endonuclease activity takes place and the molecule is shortened from both the ends.