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Published on: May 20, 2020
The Salmonella (Ames) test for mutagenicity.
1Environmental Toxicology Program/National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA.
Current Protocols in Toxicology
|October 14, 2010
Summary
The Ames test detects DNA-mutating chemicals using Salmonella bacteria. This assay identifies mutagens by observing the dose-dependent increase in his-independent bacterial colonies, crucial for toxicology studies.
Area of Science:
- Microbiology
- Toxicology
- Genetics
Background:
- The Ames test is a standard method for assessing chemical mutagenicity.
- It relies on detecting reverse mutations in Salmonella typhimurium strains.
- Mutagenic chemicals increase the frequency of his-independent bacterial colonies.
Purpose of the Study:
- To provide comprehensive protocols for performing the Ames test.
- To detail methods for handling various chemical types and quantities.
- To outline procedures for metabolic activation and strain management.
Main Methods:
- Basic plate test with and without preincubation.
- Protocols for volatile compounds, gases, and limited sample sizes.
- Preparation of the S-9 metabolic activation system.
Main Results:
- The Ames test quantifies mutagenicity by measuring the reversion frequency.
- Results are typically dose-dependent.
- The assay is adaptable for diverse chemical properties.
Conclusions:
- This unit offers a robust framework for Ames test implementation.
- It ensures reliable detection of mutagenic potential across various conditions.
- Standardized protocols enhance the accuracy and reproducibility of mutagenicity testing.
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