Isolation and mapping of a uracil-sensitive mutant of Salmonella typhimurium

A uracil-sensitive mutant of Salmonella typhimurium was isolated by diethyl sulfate mutagenesis and penicillin counterselection. This mutation identifies a new Salmonella gene that is well separated from the structural genes for arginine and pyrimidine biosynthesis. The use-1 mutation was located between the ilv gene cluster (isoleucine-valine operon) and hisR (structural gene for histidine tRNA) at 83 map units.