Metabolism of chloramphenicol by the producing organism. Some properties of chloramphenicol hydrolase

Abstract

A cell-free enzyme preparation which catalyzed the hydrolysis of chloramphenicol was obtained from Streptomyces species 3022a, a chloramphenicol-producing actinomycete. The enzyme was difficult to release from the mycelium and had low substrate affinity (Ks 0.2 mM) and activity (Vmax 2.86 nmoles/h) towards chloramphenicol. Activity was present in chloramphenicol-sensitive non-producing cultures not previously exposed to the antibiotic and did not increase during development of resistance. The results suggest that inactivation of chloramphenicol may be a subsidiary function of the enzyme.