Nutrition and metabolism of marine bacteria. V. The inhibition of growth of a marine bacterium by amino acids and the development of resistant strains

Abstract

The oxidation by, and utilization of 21 amino acids as sole carbon or nitrogen source for growth of B 16, a marine bacterium with simple nutritional requirements, has been investigated. Sixteen served as nitrogen source, 13 were readily oxidized, but only 5 served as sole carbon source. Evidence was obtained that inhibition of growth caused the failure of certain readily oxidized compounds to serve as either carbon or nitrogen source. Data presented indicate that an adaptive mechanism is available to the cells whereby, in the presence of a suitable additional carbon source, inhibition by the naturally occurring amino acids may be overcome. In addition, it was found that under certain conditions, strains of the organism capable of growing with three of these compounds, l-leucine, l-isoleucine, or l-valine, as sole carbon source may be developed. An inhibitory interrelationship between l-leucine and l-isoleucine was demonstrated.