Q.
The colonies of recombinant bacteria appear white in contrast to blue colonies of nonrecombinant bacteria because of
9662
202
NEETNEET 2013Biotechnology : Principles and Processes
Report Error
Solution:
• Blue-white screening is done to detect recombinant bacteria in cloning experiments.
• α-complementation plays a role in determining whether the bacteria is recombinant or not.
• In case of normal cells, β-galactosidase is active, thus forming blue colonies.
• In case of recombinant cells, α-complementation does not occur, thus producing no blue colour.
Hence, due to the insertional inactivation of alphagalactosidase in recombinant bacteria, the colonies of recombinant bacteria appear white in comparison to the blue colonies of non-recombinant bacteria.