ABSTRACT
It is possible to transfer DNA extracted from one bacterial culture to recipient bacteria in vitro. This is a process known as transformation, or transfection. Recipient bacteria are treated so as to increase the proportion of cells that are competent to take up exogenous DNA. These are then mixed with purified DNA and those that take up the DNA are selected as clones on agar plates. This can be useful in constructing strains of bacteria with specific genetic markers or in moving genes between species. It can also be used to identify and map linked genes. This is achieved by comparing the frequencies of transformation for individual genes with the frequency at which they show co-transformation.
