CHROMOSOMAL LOCATION OF THYMINE AND ARGININE GENES IN ESCHERICHIA COLI AND AN F' INCORPORATING THEM.

Ishibashi, Masahide (Osaka University, Osaka, Japan), Yoshinobu Sugino, and Yukinori Hirota. Chromosomal location of thymine and arginine genes in Escherichia coli and an F' incorporating them. J. Bacteriol. 87:554-561. 1964.-The gene responsible for thymine requirement or independence in Escherichia coli K-12 is located on the chromosome, near Arg(2) (arginine) and between Sm (streptomycin) and Ade (adenine). A new F' (called F(15)) carrying the Thy (thymine) gene as well as the Arg(2) gene was discovered. The Thy(+) (thymine independent) gene on F(15) relieves the defect of all Thy(-) (thymine requiring) mutants of E. coli examined, such as E. coli 15 T(-), B3, and Thy(-) mutants obtained by aminopterine treatment. It can also be transferred to Thy(-) mutants of Salmonella typhimurium and Serratia marcescens, converting them to Thy(+).