<p>A new antibiotic complex, complex 484, components 484-A and 484-B thereof and a process for their preparation are disclosed. These antibiotic substances are producible by culturing a microorganism of the species Streptomyces in an aqueous nutrient medium under submerged aerobic fermentation conditions. The substances are useful against a broad spectrum of pathogenic bacteria. Methods for their use are disclosed also.</p>
