Ames
Test
It was seen that about 90% of the agents that cause cancer in humans also cause mutations in bacteria. Working on these lines, Bruce Ames at University of California, USA developed a procedure to determine whether a chemical can induce a bacterial mutation and thus be a potential agent of cancer.
The procedure, Ames test is relatively inexpensive, accurate and rapid. A histidine requiring strain of Salmonella typhimurium is inoculated into a plate containing the culture medium lacking histidine. Normally the Salmonella strain will not grow as genes for histidine synthesis are lacking.
