Pseudomonas stutzeri RC-7, grown under iron-deficient conditions, produced catechol-type siderophore. Iron uptake was enhanced by the presence of its own siderophore. The production of iron-binding protein with molecular weight of 55,000 in the outer membrane was found to be suppressed in iron-supplemented conditions. In contrast, another protein with molecular weight of 42,000 was induced under the same conditions.