The process is called recombinant DNA technology (also known as genetic engineering). In this process, new genes are either added to or replace existing genes on a bacterial plasmid to create a recombinant plasmid, which is then introduced into bacteria for propagation and expression of the inserted gene. This typically involves cutting the plasmid and the gene of interest with restriction enzymes, joining them with DNA ligase, transforming the bacteria, and selecting for cells that harbor the recombinant plasmid.