Ames test

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Ames test

 [āmz]
a test for mutagenic substances, in which a strain of Salmonella typhimurium that lacks the enzyme necessary for histidine synthesis is cultured in the absence of histidine and in the presence of the suspected mutagen. If the substance causes DNA damage resulting in mutations, some of the bacteria will regain the ability to synthesize histidine and will proliferate to form colonies.

Ames test

(āmz),
a screening test for possible carcinogens using strains of Salmonella typhimurium that are unable to synthesize histidine; if the test substance produces mutations that regain the ability to synthesize histidine, the substance is carcinogenic.
Synonym(s): Ames assay

Ames test

n.
A test used to determine the mutagenic potential of a substance, in which salmonella bacteria that are unable to synthesize histidine are introduced into the substance, and the substance is deemed mutagenic and carcinogenic if the bacteria regain the ability to synthesize histidine.

Ames test

[āmz]
Etymology: Bruce Nathan Ames, American molecular geneticist, b. 1928
a method of testing substances for possible carcinogenicity by exposing a strain of Salmonella to a sample of the substance. The rate of mutations observed is interpreted as an indication of the carcinogenic potential of the substance tested. Also called mutagenicity test.

Ames test

A bioassay that detects genetic mutations, which is used to screen for compounds with carcinogenic potential.

Ames test

(āmz test)
A screening procedure for possible carcinogens using strains of Salmonella typhimurium that are unable to synthesize histidine; if the test substance produces mutations that regain the ability to synthesize histidine, the substance is carcinogenic.

Ames test

or

mutatest

a technique devised in the USA by Bruce Ames and an associate that is designed to screen environmental chemicals for mutagenicity. The test generally uses histidine-requiring mutant strains of the bacterium Salmonella typhimurium as the ‘tester strains’ and measures the frequency of BACK MUTATIONS where the mutants no longer require histidine supplements in their food supply. Many of the tester strains also have mutations that increase permeability to certain chemicals and enhance mutagenic effects by being defective in DNA REPAIR systems. The Ames test has been employed widely since 1975 as a check for potential CARCINOGENS, since these chemicals usually act as MUTAGENS.

Ames,

Bruce N., U.S. molecular geneticist, 1928–.
Ames assay - a screening test for possible carcinogens. Synonym(s): Ames test
Ames test - Synonym(s): Ames assay

Ames test

a test for mutagenic substances, in which a strain of Salmonella typhimurium that lacks the enzyme necessary for histidine synthesis is cultured in the absence of histidine and in the presence of the suspected mutagen treated with liver extract. If the substance causes DNA damage resulting in mutations, an increased number of the bacteria will regain the ability to synthesize histidine and will proliferate to form colonies. An important test for detecting potentially carcinogenic agents such as agricultural chemical and food additives.