The activity of 4CMB, 4HMB and BC in Saccharomyces cerevisiae JD1

3 structurally related compounds, 4-chloromethylbiphenyl (4CMB), 4-hydroxymethylbiphenyl (4HMB), and benzyl chloride (BC) were assayed for their ability to induce mitotic gene conversion in stationary phase cultures of the yeast, Saccharomyces cerevisiae JD1. This strain allows gene conversion to be scored at 2 independent loci, trp 5 and his 4. The results reported in this paper indicate that both 4CMB and BC are genetically active in yeast, producing dose-related increases in mitotic gene conversion at both the loci tested; 4HMB showed no such activity. At high survival levels 4CMB and BC showed comparable activity. However, as toxicity increased BC showed much more potent convertogenic activity, whereas with 4CMB a reduction in induced gene conversion was observed. The presence of a microsomal activation system derived from the livers of Aroclor-induced male rats did not significantly affect the activity of any of the compounds.