Chapter 32, Problem 1Q

Why are mutants used as test organisms in the Ames test?

Summary Introduction

To write:

The mutants used as test organisms in the Ames test.

Introduction:

Ames test is an employed method that uses bacteria to test whether a given chemical can cause mutations in the DNA of the test organism. It is a biological assay to access the mutagenic potential of the chemical compounds. It uses several bacterial strains that carry mutations in genes involved.

Explanation of Solution

Ames test uses several kinds of bacterial strains as Salmonella typhimurium that carry a mutation in a gene that encodes histidine. It is an auxotrophic mutant that loses its ability to synthesize histidine, utilizing the ingredients of the culture medium. The strains require histidine in their growth media.

DNA is the same in all the organisms and any living organism can be used to test for the mutagens. Bacteria can be used as the first step in the identification of potential human carcinogens. Since the bacteria require histidine to make many of their proteins, these mutant bacteria will die unless this media in which they are grown contains histidine.

Conclusion

Thus, mutants as bacterial strains are used as test organisms in the Ames test so that effect can be variable.