Enhancement of frameshift mutagenesis in Salmonella typhimurium derivatives of hisC3076 by 5-azacytidine and other agents.
The yield of frameshift revertants of Salmonella typhimurium strain hisC3076 on plates containing the mutagen 9-aminoacridine (9AA) is enhanced by the addition to the selection medium of a number of chemical agents. These include 5-azacytidine (5-azaC), naladixic acid, ethyl methanesulphonate; pre-treatment of cells with u.v. light or gamma-radiation is also effective. With the exception of u.v. which is detected as a poor mutagen in strain hisC3076, all other enhancing agents are not usually detected as mutagens in this strain. The observed synergism between 9AA and 5-azaC in recA and uvrB derivatives of hisC3076 eliminates the possibility that recA-dependent repair or excision repair is necessary. However a lack of synergism in a uvrD derivative suggests that helicase II is involved. It is suggested that the presence of 9AA in the plating medium enables the synergistic agents to be detected as mutagens.
Podger
D M
DM
CSIRO Division of Molecular Biology, Sydney, Australia.
Grigg
G W
GW
D000585:Aminacrine / Q000009:adverse effects; D001374:Azacitidine / Q000009:adverse effects*; D004269:DNA, Bacterial / Q000187:drug effects; D004357:Drug Synergism; D005020:Ethyl Methanesulfonate / Q000009:adverse effects; D009152:Mutagenicity Tests; D009154:Mutation; D012486:Salmonella typhimurium
D004269:DNA, Bacterial; D000585:Aminacrine; D005020:Ethyl Methanesulfonate; D001374:Azacitidine