[Pseudomonas microcins: characterization and effect of iron concentration].

Antibacterial substances were found in Pseudomonas, they were heat and trypsin resistant, molecular weight less than 10,000 daltons, produced in minimal media, optimum pH 7.0. Methionine and glycine inhibited them; other amino acids produced less antagonistic effect. An inverted relationship between susceptibility to microcin and Fe3+ concentration was observed in experiments with iron-depleted strains. Pseudomonas was sensitive to its own microcin in iron-free medium; this is an important finding in the study of the immunity of microcin-producing strains.