Debertoldi, M; Barale, R; Giovannetti, M
PESTAB. The following pesticides (plus a standard mutagen, MMS) have been tested for mitotic gene conversion in two different eukaryotic microorganisms, Saccharomyces cerevisiae and Aspergillus nidulans: Afugan (pyrazophos), (2-(O,O- diethyl- thionophosphoryl- 5-methyl- 6-carboxy- 1,5alpha- pyrimidine); Atrazine, 2-chloro-6- ethylamino- 4-isopropyl amino- 1,3,5-triazine; Benomyl, 1-(butylcarbamoyl)- 2-(benzimidazol) carbamic acid, methyl ester; Captan, N-trichloro methylthio- 4-cyclo hexane-1,2- dicarboximide; Daconil, tetrachloro isophthalo nitrile; Mehltaumittel, 4-cyclo dodecyl- 2,6-dimethyl morpholine; Plantvax (oxycarboxin), dihydrocarboxy- anilido methyloxathiin dioxide; Saprol [N,N-(1,4- piperazinediyl-bis- (2,2,2-tri chloroethylidene)]- bis- formamide; Wepsin (triamiphos), 5-amino-bis (dimethylamido) phosphinyl- 3-phenyl- 1,2,4- triazole; MMS, methyl methane sulphonate. In both micro organisms Captan has shown a very high converto genic activity, about 5 times more than MMS tested in the same conditions. Two pesticides, Afugan and Wepsin, were active only when tested on A. nidulans. The other pesticides resulted inactive on both micro organisms also after mammalian metabolic activation (liver-mouse microsomes). Atrazine, a widely used herbicide in maize, previously reported active as convertogen in D 4 (S. cerevisiae) only after vegetable activation, did not show any activity under mammalian metabolism. These data suggest that a particular mechanism is involved in the biological activation of this compound. The different ability to respond to the pesticides tested of A. nidulans and S. cerevisiae emphasizes the utility to use different organisms in testing chemicals. [At the 2nd International Conference of the International Assoc. of Environmental Mutagen Societies.] (Author abstract by permission)