TA102

TA102 is a bacteriological tester strain of Salmonella enterica serovar Typhimurium used in the Ames mutagenicity test. It is part of the TA-series of strains developed in the 1970s by Bruce N. Ames and colleagues to broaden the detection range of mutagens. TA102 is characterized by mutations that render it auxotrophic for histidine and by a genetic background designed to increase sensitivity to certain classes of mutagens, particularly those that cause oxidative DNA damage or DNA crosslinking.

As with other Ames strains, TA102 is used in assays that compare the number of revertant colonies able to grow without histidine on selective media, often with metabolic activation (S9 mix) to simulate mammalian metabolism. In practice, TA102 is typically employed alongside other tester strains to provide a more comprehensive mutagenicity profile. The results are reported as revertants per plate or as a fold increase over a negative control, with appropriate positive controls for different mutagen classes.

TA102 does not detect all mutagens equally well, and interpretation requires consideration of experimental conditions, including the use of metabolic activation, solvent effects, and plate density. See also: Ames test, Salmonella typhimurium tester strains. References: classic studies by Ames et al. on the development of the tester strains and guidelines for Ames test interpretation.