Bacterial mutagenicity test

Houk VS, Schaikowsky S, Claxton LD. 1989. Development and validation of the spiral Salmonella assay An automated approach to bacterial mutagenicity testing. Mutat Res 223 49-64. 

Many plasmids are known to possess three properties (1) increased resistance to the bactericidal effects of UV and chemical mutagens, (2) increased spontaneous mutagenesis, and (3) increased susceptibility to UV and chemically induced mutagenesis. Some plasmids possess all three properties others may possess just one, for example, increased susceptibility to mutagenesis (review Mortelmans and Dousman, 1986). Often the profile of activity depends on the DNA repair status of the host cell (Pinney, 1980). Plasmid pKMIOl carries DNA repair genes and has been widely used in strains used in bacterial mutagenicity tests. 

NOES (1999) National Occupational Exposure Survey 1981-83. Unpublished data as of July 1999. Cincinnati, OH, Department of Health and Human Services, Public Health Service, Centers for Disease Control, National Institute for Occupahonal Safety and Health Nohmi, T., Miyata, R., Yoshikawa, K. Ishidate Jr, M. (1985) [Mutagenicity tests on organic contaminants in city water and related compounds. I. Bacterial mutagenicity tests.] Eisei Shikenjo Hokoku, 103, 60-64 (in Japanese)... 

DiVmcenzo, GD., Hamilton, M L., Mueller, K.R., Donish, W.H. Barber, E.D. (1985) Bacterial mutagenicity testing of urine from rats dosed with 2-ethylhexanol derived plasticizers. 

Kirkland, D.J., Smith, K.L. Parmer. V. (1982a) Bacterial mutagenicity tests on 4-chloro-methylbiphenyl and 2 structural analogs. Mutat. Res., 100, 21-25... 

The conflicting set of results from bacterial mutagenicity tests is probably due to a lack of specific metabolic enzymes in microsomal preparations which were present in intact hepatocytes. 

Mutagenicity (genotoxicity). A bacterial mutagenicity test that demonstrates the induction of point (gene) mutations is always required. Some mutations result in the development of cancer. 

Nohmi T, Miyata R, Yoshikawa K, et al. 1985. [Mutagenicity tests on organic chemical contaminants in city water and related compounds I. Bacterial mutagenicity tests]. Bulletin of National Hygiene Science 103 60-64. (Japanese). 

Almost all bacterial mutagenicity tests for carbon tetrachloride have been negative. Ames tests for reverse mutations using several strains of Salmonella typhimurium, with and without metabolic activation, were mostly negative. A weakly positive geno-toxic response was reported in yeast. Negative or weak responses were observed in four studies examining unscheduled DNA synthesis. 

Justus, T., and Thomas, S.M. (1989) Evaluation of transcriptional fusion with green fluorescent protein versus luciferase as reporters in bacterial mutagenicity tests. Mutagenesis, 14, 351— 356. 

As one example the case of a bacterial mutagenicity test may be cited, where hundreds of petri dishes with the bacterial colonies grown as a result of the test, and which may be considered to constitute the test system as well as the primary data. After the end of the incubation period these petri dishes cannot be stored for too long a time, since either the bacteria (and any contaminant germs) will continue to grow, or the layer of agar growth medium will dry out, and both of these events will render the plates useless for further evaluation after some time. The petri dishes will therefore have to be discarded shortly after the end of the experiment. The actual raw data of the study to be archived are, however, the bacterial colony counts, whether they have been manually determined or automatically recorded. Thus, if it can be ascertained... 

In general, sodium selenite and sodium selenate have produced mixed results in bacterial mutagenicity test systems (Table 3M). Sodium selenite induced base-pair substitution mutations using S. typhimurium and was also positive in the transformation assay using Bacillus subtilis (Kramer and Ames 1988 Nakamuro et al. 1976 Noda et al. 1979). However, negative results have also been reported for sodium selenite both in S. typhimurium and the rec assay using B. subtilis (Lofroth and Ames 1978 Noda et al. 

CR is stated not to be genotoxic in a Salmonella bacterial mutagenicity test, a CHO forward gene mutation test (HGPRT locus), mouse lymphoma cell assay (L5178Y/tk+/tk ), and a micronucleus test (Colgrave et al, 1983). 

The well-known AMES test is a similar technique in principle. This widely used, simple, and rapid bacterial mutagenicity test detects carcinogenic effects of chemicals. It is based on two assumptions. First, cancer is commonly caused by damage to the cell DNA resulting in somatic mutations. Second, chemicals that damage bacterial DNA and induce mutations are also likely to induce mutations in mammalian cells. 

No sensitization was observed in the guinea pig test according to Magnusson-Kligman — Bacterial mutagenicity tests were negative. 

Venitt, S. Crofton-Sleigh, C. Bacterial mutagenicity tests of phenazine methosulfate and three tetrazolium salts. Mutat. Res. 1979, 68, 107-116. 

Alkyl polyglycoside did not induce reverse mutations in the tested strains of Salmonella typhimurium either with or without metabolic activation. Accordingly, alkyl polyglycoside is regarded as nonmutagenic in this in vitro bacterial mutagenicity test [107]. 

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