Genetic Engineering and DNA Manipulation

Introduction

• Genetic engineering often involves inserting a new gene into bacterial DNA.
• The DNA structure used is called a plasmid.

Tools and Techniques

Restriction Enzymes

• Example: EcoRI
• Function: Cuts DNA at specific sequences.
• Mechanism: Scans DNA for a specific base sequence (e.g., GAATTC).
  • Cuts at this point creating a 'sticky end'.

DNA Ligation

• Enzyme: DNA ligase
• Function: Joins the new DNA segment into the plasmid.

Process of Gene Insertion

1. Cutting DNA
   • Restriction enzyme EcoRI makes a cut at the specific site.
   • Creates sticky ends for the insertion of new DNA.
2. Inserting New Gene
   • New DNA is introduced into the plasmid.
3. Joining DNA
   • DNA ligase stitches the DNA strands together.

Culturing and Production

• Genetically engineered bacteria are grown in a culture medium.
• Rapid production of bacteria occurs, with each containing the new gene.
• The bacteria produce the protein coded by the inserted gene, resulting in the desired product.

Summary

• The process utilizes molecular tools such as restriction enzymes and DNA ligase to modify bacterial DNA.
• The inserted gene leads to the production of specific proteins, facilitated by the rapid bacterial growth in culture mediums.