Genetic engineering is the process of manipulating the genetic material of an organism — often to include the DNA from a foreign organism. Using the pGLO™ Bacterial Transformation Kit, students transform bacteria by introducing a gene from the bioluminescent jellyfish Aequorea victoria. The same procedure has been used to create "designer proteins" which have led to the explosion of new health treatments, agricultural applications, and environmental solutions.
Features and Benefits
- Aligns with AP Biology Lab 6
- Transforms bacteria with a jellyfish gene
- Turns the gene on and off for the study of gene regulation
Bio-Rad's exclusive pGLO plasmid is constructed with the jellyfish gene that encodes green fluorescent protein (GFP), an antibiotic-resistance gene that encodes β-lactamase protein, and the araC gene encoding a regulator protein that turns the GFP gene on and off. Bacteria transformed with pGLO plasmid are selected by ampicillin resistance; when induced to express GFP, the bugs glow fluorescent green under UV light.
How It Works
With this activity, students analyze the growth of bacteria on various media and examine the roles of external and internal factors in gene regulation. Gene expression in all organisms is carefully regulated to allow adaptation to differing conditions and to prevent wasteful production of proteins. Bacterial genes encoding the enzymes needed to metabolize the simple sugar arabinose are a perfect example. A promoter region upstream of these genes acts as a molecular on/off switch that regulates their expression. The genes are activated only when arabinose is present in the environment. Bio-Rad's pGLO plasmid incorporates the arabinose promoter, but the genes involved in the breakdown of arabinose have been replaced with the jellyfish gene encoding GFP. When bacteria transformed with pGLO plasmid are grown in the presence of arabinose, the GFP gene switches on, causing the bacteria to express GFP and fluoresce brilliant green. When students genetically reengineer bacteria with the genes from a bioluminescent jellyfish, they never forget the central mantra of molecular biology:
DNA ⇒ RNA ⇒ Protein ⇒ Trait — Green Fluorescence
- Two–session laboratory activity, 45 min per session
- Provides sufficient materials for eight student workstations, up to four students per workstation