Bioautography: a general method for the visualization of isozymes.

A new method has been developed for visualization of isozymes which are difficult or impossible to detect with standard histochemical or autoradiographic methods. The principle of this method, bioautography, is the use of a microbial reagent to locate an enzyme after gel electrophoresis. When bioautography was compared to other staining procedures, the bioautographic method yielded identical results to those observed by the histochemical method for lactate dehydrogenase (LDH) or by the autoradiographic method for the adenine phosphoribosyltransferase (APRT). Using the bioautographic method, stains for enzymes which could not be visualized by any other procedure have been developed: argininosuccinate lyase and branched-chain aminotransferase. By employing appropriately genetically marked bacterial strains, it should be possible to develop new isozyme stains for a large number of unstudied isozymes.