Main Title |
S9-Dependent Activation of 1-Nitropyrene and 3-Nitrofluoranthene in Bacterial Mutagenicity Assays. |
Author |
Ball, L. M. ;
Williams, K. ;
Kohan, M. J. ;
Lewtas, J. ;
|
CORP Author |
Health Effects Research Lab., Research Triangle Park, NC. ;North Carolina Univ. at Chapel Hill. Dept. of Environmental Sciences and Engineering. |
Year Published |
1985 |
Report Number |
EPA/600/D-86/003; |
Stock Number |
PB86-144631 |
Additional Subjects |
Toxicology ;
Bacteria ;
Bioassay ;
Nitrogen organic compounds ;
Fluoranthene/nitro ;
Pyrene/nitro ;
Mutagenesis ;
Salmonella typhimurium
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB86-144631 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
12p |
Abstract |
Nitro-substituted polycyclic aromatic hydrocarbons (N02PAH) such as 1-nitropyrene (NP) and 3-nitrofluoranthene (3-NFA), both widespread environmental mutagens, generally require activation by bacterial nitroreductases for maximal expression of their mutagenicity in the Ames Salmonella histidine reversion assay; addition of exogenous mammalian drug-metabolishing enzymes (S9 fraction) decreases their activity in the system. In contrast, in an assay of forward mutation (to 8-aza-guanine resistance) with Salmonella typhimurium strain TM677, without S9 NFA has relatively low activity (10 to 20 mutants per 10 to the 5th power survivors at 5 micrograms/ml) and NP only marginally doubles the background mutation rate. Addition of S9 protein enhances NP at 50 micrograms/ml and 80 to 100 x 10 to the minus 5 power for NFA at 5 to 10 micrograms/ml. Therefore generation of active genotoxic intermediates in the forward mutation system may proceed through metabolic pathways other than the previously-defined bacterial nitro-reduction. Previously-identified oxidative metabolites of NP are known to be mutagenic. |