Salmonella test: relation between mutagenicity and number of revertant colonies.
This paper describes a model that relates the actual effect measured in the Salmonella test, i.e., the number of revertant colonies, to the mutation rate induced by a stable test compound having no side effects and acting without a time-lag. A maximum-likelihood estimator for the mutation rate is derived. Furthermore some side effects (mortality, increase in generation time, other mutations) are included in more extensive models. Side effects can cause a non-linear dose-response relation. Factors delaying the effect of the compound lead to an apparently higher mutation rate if a higher histidine dose is applied or a smaller inoculum is used. Factors slowly decreasing the effect of the compound reverse this result. Secondary effects of the test compound on the bacteria result in a non-linear dose-response relationship.
van der Hoeven
N
N
Department of Biology, MT-TNO, Delft, The Netherlands.
Kooijman
S A
SA
de Raat
W K
WK
D008433:Mathematics; D015233:Models, Statistical; D009152:Mutagenicity Tests / Q000379:methods*; D009153:Mutagens / Q000494:pharmacology*; D011336:Probability; D012486:Salmonella typhimurium / Q000187:drug effects*
D009153:Mutagens