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. 1973 Aug;70(8):2281–2285. doi: 10.1073/pnas.70.8.2281

Carcinogens are Mutagens: A Simple Test System Combining Liver Homogenates for Activation and Bacteria for Detection

Bruce N Ames 1, William E Durston 1, Edith Yamasaki 1, Frank D Lee 1
PMCID: PMC433718  PMID: 4151811

Abstract

18 Carcinogens, including aflatoxin B1, benzo(a)pyrene, acetylaminofluorene, benzidine, and dimethylamino-trans-stilbene, are shown to be activated by liver homogenates to form potent frameshift mutagens. We believe that these carcinogens have in common a ring system sufficiently planar for a stacking interaction with DNA base pairs and a part of the molecule capable of being metabolized to a reactive group: these structural features are discussed in terms of the theory of frameshift mutagenesis. We propose that these carcinogens, and many others that are mutagens, cause cancer by somatic mutation. A simple, inexpensive, and extremely sensitive test for detection of carcinogens as mutagens is described. It consists of the use of a rat or human liver homogenate for carcinogen activation (thus supplying mammalian metabolism) and a set of Salmonella histidine mutants for mutagen detection. The homogenate, bacteria, and a TPNH-generating system are all incubated together on a petri plate. With the most active compounds, as little as a few nanograms can be detected.

Keywords: frameshift mutagens, aflatoxin, benzo(a)pyrene, acetylaminofluorene

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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