Muta-Lab™ Testing Educational Kit
Ames Test for the Classroom
Timeline: 150 Minutes to 225 Minutes About the Muta-LabTM: The Muta-LabTM detects mutagenic activity or mutagenic materials in environmental water, sediment and air samples as well as food products, cosmetics and biological fluids. Mutagenic materials may be hazardous due to their ability to alter the structure and function of DNA. The Muta-LabTM illustrates how different chemicals, compounds, and environmental samples are tested to ensure they are safe for human consumption, use, or exposure. |
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Reaction: A chemical that is mutagenic strongly suggests it is also carcinogenic. The tester strains of bacteria have been mutated from their natural phenotype to be unable to produce histidine, in the case of Salmonella, or tryptophan, in the case of E. coli. When grown in a medium that contains little or no histidine (or tryptophan) the bacteria are unable to grow. However, in the presence of a mutagen, the bacteria are mutated back to their natural phenotype and survive. The Muta-Lab™ assay uses altered E. coli strains that contain mutations at selected sites in the lactose metabolism pathway which are reverted by a specific type of interaction, like a frameshift or base-pair mutation, and permits the mechanism of DNA damage to be identified. The use of reversion mutations to detect genetic alterations makes the modified E. coli strains ideal screening tools to assess mutagenic potencies of chemical mixtures in low concentrations that may exert synergistic effects when present together. Exposure and incubation of the bacterial strain with a test sample, followed by selection of the revertant mutant colonies in a lactose deficient growth media provides rapid and facile identification and quantification of mutagenesis. |
EDUCATIONAL LAB HANDOUT
Download the Handout which includes Educator Resources, Student Handout, Preparation, and Lab Procedure. |
Learning Goals (see About Us for Details): LG 1, LG 2, LG 3, LG 4, LG 7, LG 8, and LG 9
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