Chapter 14, Problem 14STP

Summary Introduction

To determine:

The definition of restriction enzymes and their importance in genetic engineering.

Introduction:

Genetic engineering has many applications from health to agriculture. There are some basic tools involved in genetic engineering that can be used to manipulate DNA and to isolate genes from genome. It makes possible to produce organisms that contain individual genes from another organism. Restriction enzymes are an important tool in genetic engineering.

Answer to Problem 14STP

Restriction enzymes are proteins found in some bacteria that can make cuts at specific sites in DNA.

Importance- They are used to create DNA fragments with sticky or blunt ends that can join with other DNA fragments.

Explanation of Solution

Some bacteria contain proteins called restriction enzymes that recognize and bind to specific DNA sequences and cleave the DNA within that sequence. The ends of DNA fragments created by restriction enzymes may have sticky ends or blunt ends. The sticky ends produce single stranded DNA that is complementary. The blunt ends do not have regions of single stranded DNA.

Examples:

EcoRV − This enzyme creates blunt ends.

EcoRI − This enzyme creates sticky ends.

Importance- Since their discovery in late 1960s scientists have identified and isolated hundreds of restriction enzymes. They use these enzymes as powerful tools for isolating specific genes or regions of genome. When restriction enzymes cleave genomic DNA, they create fragments of varying sizes that are unique to each individual.