The presence of a chromogenic substrate gives blue coloured colonies of bacteria. Insertional inactivation would stop production of which of the following enzyme such that colonies do not produce any colour.

Question

The presence of a chromogenic substrate gives blue coloured colonies of bacteria. Insertional inactivation would stop production of which of the following enzyme such that colonies do not produce any colour. (A) Beta-galactosidase (B) Alpha galactosidase (C) Alpha lactalbumin (D) All of the above

Tardigrade Admin · Accepted Answer

In PUC plasmid, Lac Z gene is used as a selectable marker. If a transformant is grown in a medium having chromogenic substrate it produces enzyme Beta-galactosidase due to which blue coloured colonies are produced. Insertion of foreign DNA segment in Lac Z gene fails to produces enzyme Beta-galactosidase as a result colourless colonies are produced.

Q. The presence of a chromogenic substrate gives blue coloured colonies of bacteria. Insertional inactivation would stop production of which of the following enzyme such that colonies do not produce any colour.

Beta-galactosidase

Alpha galactosidase

Alpha lactalbumin

All of the above