Trace Metal Control of Bacterial Flagellation

Abstract

SPECIFIC alterations in the normal battery of biosynthetic processes often occur when moderate changes are made in the balance of metallic ions in the environment. In microbial systems, for example, the quantities synthesized of organic acids, porphyrins, vitamins, antibiotics, toxins, enzymes, lipids, and polysaccharides are controlled by precise balances of metallic ions that permit, but are not necessarily optimal for, vegetative growth. Likewise, the execution of such physiological processes as cell division; sporulation; germination; plasmodia and vesicle formation; and adsorption, induction, and synthesis of bacterial viruses depends on concentrations of specific metallic ions that differ from the minimum quantities needed for synthesis of protoplasm. Indeed, the tolerance of normal vegetative growth to fluctuation of the metallic ion environment is considerably greater than the fluctuation tolerated by a specific biosynthetic or physiological process¹.