Question

If a putative protein sequence is cloned in an expression vector and the expressed protein is not showing protease activity, then which of the following is not correct?

(a) The protein is not protease

(b) The protein can be incorrectly folded which can block the protease activity

(c) There might be some other cofactor required for protease activity

(d) The most commonly used expression system is E.coli

This question was addressed to me in an interview for job.

The above asked question is from Applications of Genetic Engineering in chapter Genetic Engineering of Genetic Engineering

Answer 1

Right answer is (a) The protein is not protease

To elaborate: If the putative protein sequence is cloned and the expressed protein is not showing protease activity, it is not necessary that it is not protease. Suppression of protease activity can be because of incorrect folding or that some cofactor is required for protease activity. The most commonly used expression system is E.coli.