Thursday, January 27, 2011

Glowing Bacteria: Transformation of pGLO plasmid from sea jelly to bacteria

Introduction:
a) Genetic transformation is the process in which a gene of interest is inserted into or taken up by another organism's cell (usually a bacterium), changing the organism's trait(s). Transformation can be used to transfer a insect resistant gene into crop plants or to enable bacteria to digest oil spills. In this lab, we will be transferring a sea jelly's GFP gene (Green Fluorescent Protein) contained in a pGLO plasmid into bacteria to make the bacteria glow! The pGLO plasmid also contains a gene for ampicillin resistance and a special gene regulation system which can be used to control expression of the fluorescent protein in transformed cells. The gene for GFP can be switched on by adding sugar arabinose to the bacteria's nutrient medium. The bacteria will also be grown on antibiotic plates, killing all the bacteria which did not take up the pGLO and thus do not have antibiotic resistance. This will allow us to determine which bacteria contain the pGLO plasmid.
b) The purpose of this experiment is to transfer the pGLO plasmid (which is derived professionally from a sea jelly gene) into the bacteria. Hopefully we will be able to see the bacteria glow, like a sea jelly! It is a simple way of seeing how genetically modified organisms are made in the real world of biotechnology.
c) There are many techniques we will be utilizing in this lab. Among them are proper pipetting techniques, to fill the test tubes with the Calcium Chloride solution and to put the pGLO plasmid into the tube.. We will use sterile loops to collect bacteria from a dish and put the bacteria in the solution. Heat shock is a technique used to induce transformation - the solution of CaCl2, plasmids, and bacteria is iced for about 10 minutes before put into a hot water bath and then iced again. This causes a sort of current, allowing plasmids to go in through the bacteria's pores. After heat shock, we will use pipetting techniques to transfer the solution onto a petri dish. Incubation of the dish will allow bacteria to grow faster so we can see the results!
d) My hypothesis is that the experiment will work! I think we will be successful and will be able to create glowing bacteria.

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