Friday, October 3, 2008

LAB - Genetic transformation - making E. coli glow and survive ampicilin


Genetic transformation is the process through which a cell takes up, and expresses, a new piece of genetic material. Usually the organism (e.g. a bacterium) is provided with a new trait that is identifiable after transformation.

In this lab we transformed a strain of E. coli with the plasmid (a piece of circular DNA) pGLO containing the genes Beta Lactamase (ampicilin [an antibiotic] resistance) and Green Fluorescent Protein (GFP), a protein naturally found in the bioluminescent medusa ("jellyfish") Aequorea victoria.

The plasmid is forced into the bacteria through heat shock (42º C - 50 sec). The bacteria will take the plasmid, which contains several genes, including the ones of interest, and it will express them. In the presence of the sugar arabinose (in the culture medium) the GFP will be turned on and expressed, causing the bacteria to glow under UV light.

A couple of useful pics:

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2 comments:

Anonymous said...

When did you say our 1st test would be?

Alonso Córdoba said...

Tuesday October 14th!