Abstract
The growth of the bacitracin producing strain Bacillus licheniformis AL and the bacitracinnegative mutant SB 319 have been compared at different cultural conditions. Concentrations of the metal chelator EDTA which strongly inhibited the growth of the non‐producer only slightly inhibited the growth of the bacitracin producer. The inhibitory effect of EDTA upon SB 319 was reversed by the addition of excess manganese(II)ions, cobalt(II)ions, or zinc(II)ions to the culture. The addition of several other ions had no such effect. The addition of bacitracin to the EDTA inhibited mutant also promoted growth. When the non‐producer was mutated back to bacitracin production, the inhibitory effect of EDTA was lost. It is suggested that bacitracin may normally promote the uptake of several trace metals during growth of the producer organism.