Is Escherichia coli ATCC 25922 a colicin producing strain? (a note).

The well-characterized strain of Escherichia coli ATCC 25922 recommended and widely used as a control Gram-negative bacterium for various laboratory experiments, especially for antibiotic susceptibility assays, was found to be antagonistic against another E. coli strain which is uniquely susceptible to fusidic acid, an antibiotic mainly active against Gram-positive bacteria. This antagonistic property appears to be selective, since it was not found against other E. coli or Staphylococcus aureus strains.