Mutagenesis assay, Salmonella

Zeiger E. 1987. Carcinogenicity of mutagens Predictive capability of the Salmonella mutagenesis assay for rodent carcinogenicity. Cancer Res 47(5) 1287-1296. 

Three primary tests are incorporated in the health effects area. The microbial mutagenesis assay is based on the property of selected Salmonella typhimurium mutants to revert from a histidine requiring state to prototrophy due to exposre to various classes of mutagens. The test can detect nanogram quantities of mutagens and has been adapted to mimic some mammalian metabolic processes by the addition of a mammalian liver microsomal fraction. The test is used as a primary screen to determine the mutagenic activity of complex mixtures or component fractions. 

TBHP did not produce a genotoxic response in the cell transformation assay, but did produce a mutagenic response in the Ames Salmonella) and mouse lymphoma mutagenesis assays. TBHP was tested for the induction of sex-linked recessive lethal mutations in Drosophila melanogaster, and was positive at a dose of 2000 ppm when administered to males by feeding. 

Procyanidins with different degrees of polymerization such as dimers, trimers, and polymers from extracts of different natural sources were found to be nonmutagenic in the Salmonella mutagenesis assay. Moreover, the mutagenic impurity in procyanidin B-4 was isolated by reversed-phase high-performance liquid chromatography (HPLC). Procyanidin B-4 was identified as rutin (flavonol O-glycoside, 3) (Fig. 22) [55]. 

Other microbial mutation, repair and recombination assays have also been used in chemical screening, however, the data base for carcinogenicity-mutagenicity correlation established with these in vitro test systems is relatively limited at this time.62-70 At present, the Ames Salmonella assay appears to be the most generally applicable screen for the detection of chemical mutagens. No other mutagenesis assay has been shown to respond to such a wide group of chemical types as the Salmonella mutants. 

Of all the short-term assays, the Ames Salmonella test is clearly the best validated and most widely used and will continue to be so for a number of years to come. The assay has an excellent record for identifying organic carcinogens, particularly carcinogens which are in the aromatic amine and polycyclic hydrocarbon classes. " In addition, positive results in the Ames assay and several other short-term mutagenesis assays, have been predictive of carcinogenic activity in rodent assays for a number of compounds with widespread human exposure. Examples of these include the food preservative furylfuramide AF-2 which was used extensively in Japan from 1965 to about 1977 the flame-retardant tris-B-P (tris[2,3-dibromopropyl]phosphate) which was used to treat children s sleepwear from 1972 to 1977 and aromatic amine components of hair dye preparations. 

Figure 4. Effects of variation of initial water content on mutagenicity of ground beef Samples are fried at 200 °C for 6 min per side and the basic fraction is tested for activity in the Salmonella mutagenesis assay. (The and O are data from two separate experiments.) The original fat-to-protein ratio of approximately 0.8 in the ground beef was maintained in these samples.

PAHs are known to be absorbed through the skin after topical application as demonstrated by elevated levels of several PAHs in blood (22). Urinary excretion of 1-hydroxypyrene, a fluorescent metabolite of pyrene, has also been used as a marker of internal dose of coal tar (23—24). Elevated levels of sister chrcmiatid exchange (SCE) and chromosomal aberrations in peripheral blood lynphocytes and of urinary mutagens, measured by the Salmonella mutagenesis assay, have also been found (24-26). 

Rosin, M.P., and Stich, H.F., 1979, Assessment of the use of the Salmonella mutagenesis assay to determine the influence of antioxidants on carcinogen-induced mutagenesis, Int. J. 

Shimada T, Swanson AF, Leber P, et al. 1985. Activities of chlorinated ethane and ethylene compounds in the Salmonella microsome mutagenesis and rat hepatocyte/DNA repair assays under vapor phase exposure conditions. Cell Biol Toxicol 1 159-179. 

Monomethylhydrazine-induced mutagenesis was not observed in Ames Salmonella/ microsome with activation (Matheson et al. 1978). In vivo tests in mice (dominant lethal, revertants in host-mediated assay), and dogs (micronuclei) were negative (reviewed in Trochimowicz 1994). However, in vitro chromosomal damage in human and rat tissue has been demonstrated, although in vivo liver DNA damage (as determined by DNA alkaline elution) was equivocal (reviewed in Trochimowicz 1994). 

Aubrecht, J., Osowski, J.J., Persaud, P., Cheung, J.R., Ackerman, J., Lopes, S.H. and Ku, W.W. (2007) Bioluminescent Salmonella reverse mutation assay a screen for detecting mutagenicity with high throughput attributes. Mutagenesis, 22, 335-342. 

Lofroth, G, Nilsson, L. Andersen, J.R. (1986) Stracture-activity relationship of nitroalkane-induced mutagenicity in the Ames Salmonella assay. Genetic toxicology of environmental chemicals, Part B Genetic effects and applied mutagenesis. Prog. din. biol. Res., 209B, 149-155... 

Ackerman J, Sharma R, Hitchcock J, et al. Inter-laboratory evaluation of the bioluminescent Salmonella reverse mutation assay using 10 model chemicals. Mutagenesis. 2009 24(5) 433-438. 

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