Temperate bacteriophages of Escherichia coli O119:B14.

Lysogeny was detected in 98.8% of the 343 Escherichia coli O119:B14 strains. A suitable indicator strain E. coli KS was selected to demonstrate the presence of temperate phages in this serotype. A great diversity in the temperate population was observed based on their lytic patterns and neutralization studies. No definite relationship could be established between the biochemical reactions and the flagellar antigens of the lysogenic strain and its temperate phage though some temperate phages released by E. coli O119:B14 strains with certain flagellar antigens did give specific lytic patterns and were serologically identical. Lysogenic strains, which did not release temperate phages spontaneously, were u.v. inductible. Cross-reactions with lysogenized colonies which were immune to corresponding phages also confirmed diversity of temperate phages in E. coli O119:B14.