Biotechnology Principles And Processes Part 2

TOOLS AND TECHNIQUES#

1. Historical Development

• 1963: Werner Arber discovered restriction enzymes in E. coli bacteria
• 1968: Hamilton Smith isolated and characterized first restriction enzyme Hind II

2. Types of Restriction Enzymes

• Exonucleases: Remove nucleotides from DNA ends sequentially
• Endonucleases: Cut DNA at specific internal recognition sequences

3. Key Characteristics

• Recognize palindromic sequences that read same forward and backward
• Create specific cuts in DNA with either blunt or sticky ends
• Named using first letter of genus and two of species (e.g., EcoRI)
• Originally isolated from bacterial strains as defense mechanism