Forward mutation bacterial assay

In 1997, Busby and co-workers reported that 2-nitrofluoranthene, an important product of atmospheric transformations (vide infra) was inactive in MCL-5 cells but a potent mutagen in hlAlv2 cells another important atmospheric reaction product, the nitrophenanthrene lactone 2-nitrodibenzopyranone (XI), was inactive in both hlAlv2 and MCL-5 cells. Furthermore, it was nonmutagenic in the forward mutation bacterial assay in the absence of rat liver postmi-tochondrial supernatant (-S9) but was mutagenic with the addition of S9 mix. 

Busby and co-workers (1995) compared the mutagenicities of BaP and five dibenzopyrenes in the Salmonella typhimurium TM677 forward mutation bacterial assay (+ PMS) to three in the MCL-5 human cell assay. The powerful carcinogen dibenzo[a,/]pyrene was 50 times more potent than BaP in human cells (vide supra) however, it was only 1.7 times as potent as BaP in the bacterial assay. Interestingly, there was a 10,000-fold range between the most and least mutagenic PAH in MCL-5 human cells vs a range of only 4 in the bacterial cells. 

In an analogous set of studies at four cities across southern California (see Fig. 10.23), Hannigan and co-workers (1996) employed the Salmonella typhimurium TM677 forward mutation bacterial assay (Skopek et al., 1978b Busby et al., 1994a) to determine the seasonal and spatial variation of the bacterial mutagenicities of fine ambient aerosols. The 1993 annual... 

The genotoxic potential of brinzolamide was evaluated by the bacterial reverse mutation assay (Ames test) with S typhimurium and E coli, an in vitro mouse lymphoma forward mutation assay (MLFMA), an in vivo... 

As with the Salmonella reversion assay, this shortterm test is conducted both without (— PMS) and with metabolic activation produced by addition of post-mitochondrial supernatant containing rat liver enzymes ( + PMS). These terms are equivalent to — S9 and + S9 in the Ames reversion assay we use the latter designation for both types of bacterial assays. A more sensitive micro-forward mutation bioassay using this TM677 strain to determine the mutagenicity of indoor air particles, including ETS and wood smoke, is described by Lewtas et al. (1987). 

In general, bacterial mutagenicity assays rely on one of three mutational schemes reverse mutation, forward mutation, and DNA damage. 

Cariello NF, Narayanan S, Kwanyuen P, et al. A novel bacterial reversion and forward mutation assay based on green fluorescent protein. Mutat Res. 1998 414(l-3) 95-105. 

In in vitro (bacterial reverse mutation, CHO/ HGPRT forward mutation, and rat lymphocyte chromosomal aberration assays) and in vivo (mouse bone marrow micronucleus assay) tests, fexofenadine hydrochloride revealed no evidence of mutagenicity. 

Isophorone induced sister chromatid exchanges but not chromosome aberrations in Chinese hamster ovary cells. Isophorone was positive in L5178Y tk- -/tk — mouse lymphoma cell forward mutation assay without metabolic activation. Isophorone was negative in tests with Salmonella typhimurium bacterial strains... 

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). 

Hayes, S. Gordon, A. Sadowski, 1. Hayes, C. RK bacterial test for independently measuring chemical toxicity and mutagenicity short-term forward selection assay. Mutat. Res. 1984, 130, 97-106. 

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