Question

Which of the following is not a consequence of deletion in the b region?

(a) Excision of the prophage on induction is prevented

(b) It reduces the amount of endogenous phage DNA in the packaging mix

(c) It reduces the amount of exogenous phage DNA in the packaging mix

(d) It reduces the level of background non-recombinant phage

I have been asked this question in an interview for internship.

I want to ask this question from Cloning in Lambda in section Other Vector Systems for E of Genetic Engineering

Answer 1

Right option is (c) It reduces the amount of exogenous phage DNA in the packaging mix

To elaborate: The deletion in the b region is responsible for preventing the excision of the prophage on induction. It reduces the amount of endogenous phage DNA in the packaging mix and thus resultantly it reduces the level of background non-recombinant phage.