What are Competent Cells?
Bacterial cells that can take up foreign DNA from the environment through a process called transformation are known as competent cells. Griffith first reported it in Streptococcus pneumoniae.
E. coli cells usually take up DNA when their cell walls are modified. These cells can be enabled by calcium chloride and heat treatment. Fast growing cells can easily make more than cells in other stages of growth.
Cells can express genetic information acquired after transformation. This technique is widely used to introduce recombinant plasmid DNA into competent bacterial cells. This process requires no donor cell, but only DNA in the surrounding environment.
Principle of Competent Cells
Competent cells have modified the cell wall so that DNA can pass through it more easily. Some cells must be treated with certain chemicals or electric currents to become competent.
Treatment with calcium ions is a common method for the preparation of these cells. Bacterial cells can also take up DNA through a process called electroporation.
Methods of Preparation of Competent Cells
Bacteria take DNA from the environment through modification, splicing and transformation. The foreigner directly enters the bacterial cell through DNA modification. For this to happen, the cell must be in an enabled state.
Frederick Griffith was the first who discovered the beauty of nature. He injected mice with a slimy strain of pneumococcus, and the mice died.
That is why this species is known as a poisonous species. However, mice injected with the non-toxic strain (non-toxic strain) did not die.
Heat killing removes fuel stress toxins. Hot killed smooth tension mixed with rough tension. The dry form took a slender form and became virulent. This indicates that thermally stable inorganic materials derived from viscous stress accelerated the transformation.
In this laboratory, cells are transfected with DNA. Competent cells can be synthesized in two ways:
Calcium chloride: This method was proposed by Higa and Mandel. Bacterial cells were treated with calcium chloride and then exposed to high temperature immediately.
This is known as heat shock therapy.
Electrolysis: This process involves an electric field to increase the conductivity of cells. Also known as electrical permeability.