Question

Why and how bacteria can be made competent?

Answer 1

Hint: Bacterial cells are a gel-based matrix composed of water, nutrients, enzymes, wastes, and other gases along with other cellular organelles such as chromosomes, ribosomes, and plasmids.

Complete Answer:
Competent cells are defined as those cells that possess the ability of taking up the DNA present in the external environment. Bacterial cells are made competent with the specific gene introduction so that it becomes potent enough to take up the extracellular DNA to exhibit the process of recombinant DNA replication for its future well-being and adaptability.

There are two ways by which competent cells can be made,
1) Artificial competence:
In this method, the cells are made permeable to DNA under laboratory conditions. There are two ways by which this is generally done,
(I) Electroporation:
In this method, the cells are placed in an electric field in order to increase their permeability. Once the permeability is increased, the DNA is made to enter inside the cell.
(II) Calcium chloride:
In this method, the cells are treated using calcium chloride after which they are exposed to high temperatures.

2) Natural competence:
In this method, the bacterial cell takes up the DNA from the surroundings naturally via the process of transformation, conjugation, and transduction. This method was discovered by Frederich Griffith when he injected a smooth strain of pneumococcus in mice which led to the death of mice.

Note: Natural competence in bacteria helps in changing the cell’s genotype via homologous recombination, thereby leading to natural transformation. This helps the bacteria in surviving over adverse conditions.