NEETZoologyBiotechnology - Principles and Processes
What is the method used to increase the efficiency of DNA entering the bacterium through its cell wall?
Options
- AInjecting DNA directly into the nucleus
- BUsing a high velocity micro-particles
- CUsing a disarmed pathogen
- DTreating cells with a specific concentration of a divalent cation
Correct answer
D. Treating cells with a specific concentration of a divalent cation
Step-by-step solution
Since DNA is a hydrophilic molecule, it cannot pass through cell membranes. Why? In order to force bacteria to take up the plasmid, the bacterial cells must first be made ‘competent’ to take up DNA. This is done by treating them with a specific concentration of a divalent cation, such as calcium , which increases the efficiency with which DNA enters the bacterium through pores in its cell wall. Recombinant DNA can then be forced into such cells by incubating the cells with recombinant DNA on ice, followed by placin