RESTRICTION ENZYMES AND THEIR USES IN SPECIFIC SEQUENCING TO PRODUCE PREDICTABLE FRAGMENT OF DNA MAKING GENETIC ENGINEERING SIMPLY

Abstract

Restriction enzymes are the bedrock for genetic engineering through which many successful manipulation and modification of DNA fragment by molecular biologist had been carried out to achieve a desired gene or trait to enhance human selective evolutions on mature. Restriction enzymes are protein enzymes that recognize specific nucleotide sequence either in double or single strand DNA and cleave both strands of DNA containing those sequences (Robert et al., 1976). Restriction enzymes are discovered during an experiment to determine the ability of a bacteriophge (the name given to viruses that infect bacteria) to infect two different strains of Escherichia coli strain B and strain K in 1970. Such enzymes, found in bacteria and archaea, are thought to have evolved to provide a defense mechanism against invading viruses (Arber and Linn, 1969). Inside a bacterial host, the restriction enzymes selectively cut up foreign DNA in a process called restriction; host DNA is methylated by a modification enzyme (a methylase) to protect it form the restriction enzyme;s activity. Collectively, these two processes form the restriction modification system. To cut the DNA, a restriction enzyme makes two incisions, once through each sugar-phosphate backbone (double helix).