MODE OF ACTION OF CHLORAMPHENICOL IV

Abstract

One of the hypotheses concerning the action of chloramphenicol on bacterial growth and protein synthesis assumes that the antibiotic acts as an antimetabolite of some amino acid or other substance necessary for protein metabolism and growth. The presence of phenylalanine, tryptophan, glycine, aspartic acid and p-aminobenzoic acid in logarithmic-growth phase cultures of Escherichia coli strain B failed to reverse the inhibitory effect of chloramphenicol under a variety of experimental conditions. Similarly, no reversal was demonstrated in systems which employed a phenylalanine-requiring mutant of E. coli or in Leuconostoc citrovorum which requires citrovorum factor for growth. Antagonism of amino acids is not the mechanism by which chloramphenicol exerts its inhibitory action.