Salmonella strains and mammalian cells genetically engineered for expression of sulfotransferases

Rat and human sulfotransferases (STs) were expressed in his(-) S. typhimurium strains. These new bacterial strains detected various mutagens which are difficult to recognize in traditional test systems, including benzylic alcohols derived from polycyclic aromatic hydrocarbons, hycanthone and 1'-hydroxysafrole. STs were also stably expressed in V79 Chinese hamster cells, which do not express endogenous ST and are suitable for the detection of genotoxic effects. Positive responses in these test systems were observed with various benzylic alcohols, including benzo[a]pyrene-7,8,9,10-tetrols. We demonstrate that a few reactive sulfuric acid conjugates are efficiently detected as genotoxicants only when generated directly within the indicator cell.