PATHOLOGY

Detailed explanation-1: -Definition. A restriction enzyme is a protein isolated from bacteria that cleaves DNA sequences at sequence-specific sites, producing DNA fragments with a known sequence at each end. The use of restriction enzymes is critical to certain laboratory methods, including recombinant DNA technology and genetic engineering.

Detailed explanation-2: -The first step in the development of recombinant DNA technology was the characterization of restriction endonucleases-enzymes that cleave DNA at specific sequences. These enzymes were identified in bacteria, where they apparently provide a defense against the entry of foreign DNA (e.g., from a virus) into the cell.

Detailed explanation-3: -This is known as recombinant DNA technology. A common technique in genetic engineering is to insert a new gene into a loop of bacterial DNA called a plasmid. “The molecular tool used to cut DNA is a restriction enzyme such as EcoR1.

Detailed explanation-4: -The plasmid is cut with the same restriction enzymes so it gets the same sticky ends. The sticky ends on the plasmid stick with the ones on the gene. The gene and the plasmid are joined together using an enzyme called DNA ligase . The vector is transferred back into the bacteria host cells.