Test Biotechnology:Principles and Processes
- Identify the selectable markers in the diagram of E. coli vector shown above.
- How is the coding sequence of
-galactosidase considered a better marker than the ones identified by you in the diagram? Explain.
- Ampicillin resistance marker and tetracycline resistance markers.
- Chromogenic selectable markers show insertional inactivation. A recombinant DNA is inserted within the coding sequence of an enzyme, â-galactosidase inactivating the enzyme. The presence of a substrate gives blue coloured colonies if the plasmid in the bacteria does not have an insert. Presence of insert results into insertional inactivation of the â-galactosidase and the colonies do not produce any colour.