Genetic analysis of Escherichia coli O111:B4, a strain of medical and biochemical interest

Abstract

E. coli O111:B4 is of considerable interest because of both its pathogenicity and usefulness in basic research. This strain of E. coli was discovered in 1945 to be the main cause of nonspecific gastroenteritis of babies. E. coli O111:B4 is still frequently isolated from babies suffering from acute diarrheal episodes. E. coli O111:B4 has also been used by several laboratories for the analysis of lipopolysaccharide structure and outer membrane composition, structure, and assembly. Procedures have been worked out which allow the genetic analysis of E. coli O111:K58:H2 (O111:B4). The approximate map position of mutant loci was determined by mating with 15 Hfr strains of E. coli K-12. In addition, P1 transduction procedures were used for establishing relative gene order and linkage for any region of the E. coli O111:B4 chromosome. To obtain these, it was necessary to select for a rare P1 lysogen since E. coli O111:B4 is resistant to phage P1. Finally, genetic homology between E. coli strains K-12 and O111:B4 is suggested since they can form stable haploid hybrids, and several loci have similar map positions in the two strains.