The test is a biological assay used to assess the mutagenic potential of chemical compounds. The method involves using several strains of bacteria (Salmonella, E. coli) that carry mutations in genes involved in histidine synthesis. These strains require histidine for growth but are unable to produce it.The method is used to test the capability of certain chemicals to cause mutation in histidine encoding gene of His-Salmonella strain culture such that they regain the ability to synthesize histidine (His+). Chemicals responsible for reverting the mutation are called mutagens and the Ames test is used to identify potential carcinogens.
The "Ames" test carries the name of Profesor Bruce Ames from the University of California who developed this test.