Salmonella–Escherichia Hybrids

Abstract

UNTIL recently, genetical studies with Salmonella typhimurium have been carried out mainly by the transduction method. In an effort to facilitate such studies, we attempted to develop a means of applying conjugation techniques also, using S. typhimurium and Escherichia coli, since Baron and his collaborators¹ had been able to produce hybrids between these two bacteria. We have been successful in experiments with a Salmonella culture carrying a mutator gene (mut) and a culture of E. coli strain K-12 carrying the factor for high frequency of recombination (Hfr). The mutator strain was isolated by Miyake² from strain LT-7. Its main characteristic is a 10- to 100-fold increase in spontaneous mutability.