Transformation of Cells

Overview and Definition

Transformation in biology is the process by which the genetic makeup of a cell is changed by introduction of DNA from the external environment.
This process is common in certain bacteria and allows them to adapt and survive under various conditions.
The inserted foreign DNA sequence may alter the cell’s function or generate a new characteristic.

DNA from the environment is taken up by a competent bacterial cell.
In some bacteria, competence for transformation is natural and may be induced by environmental conditions such as starvation or during specific phases of growth.
In laboratory settings, bacterial cells are usually made competent artificially through heat-shock or chemical treatment.
Once inside the cell, the foreign DNA incorporates itself into the host chromosome which may result in a change of function in the bacterium.

Transformation is utilized extensively in genetic engineering to introduce new genes into bacteria for the production of useful substances like insulin.
This process is also used to create recombinant DNA for studying gene functions and for mapping of the genome.
Other applications include production of genetically modified organisms and the study of DNA repair mechanisms in cells.

The rate of successful transformation can be low as not all cells are naturally competent and artificial competence has limitations.
However, the use of antibiotics to select for transformed cells greatly enhances the success rate in the lab setting.
Transformation allows for rapid evolution of bacteria, contributing to their survival.
It is beneficial for scientific progress as it offers a tool for studying genes and for creating genetically modified organisms.