Why is salmonella used in the Ames test?

Salmonella typhimurim was the bacterial strain used in the first Ames test performed and developed by Bruce Ames and his group at UC Berkeley back in the 1790s. Since then, an extensive database of mutant S. typhimurim strains has been made available. More importantly, bacteria, such as S. typhimurim, are easy and inexpensive to culture, require no special equipment, and provides rapid results.