Question

Which of the characteristics is present in lacZ gene?

(a) It encodes for beta galactosidase enzyme

(b) Beta galactosidase enzyme is responsible for cleaving monosaccharides into the constituent elements

(c) It doesn’t cleaves a substrate called as X-gal

(d) But if X-gal is cleaved, it liberates pink coloured dye

The question was asked at a job interview.

My question is from Cloning using a Simple Plasmid and Alpha Complementation in portion Simple Cloning of Genetic Engineering

Answer 1

Correct answer is (a) It encodes for beta galactosidase enzyme

For explanation I would say: lacZ gene encodes for beta galactosidase enzyme. This enzyme is responsible for cleaving of disaccharides into monosaccharides. It cleaves a substrate known as X-gal, which then liberates a blue dye.