MICROBIOLOGICAL DEGRADATION OF TETRACYCLINES

Meyers, Edward (Squibb Institute for Medical Research, New Brunswick, N.J.) and Dorothy A. Smith. Microbiological degradation of tetracyclines. J. Bacteriol. 84:797–802. 1962—The degradation of tetracyclines by an ascomycete, Xylaria digitata, was demonstrated. Washedcell suspensions were capable of degrading tetracycline, 5-hydroxytetracycline, 7-chlortetracycline, 7-chlor-6-demethyltetracycline, 2-acetyl-2-decarboxamido-5-hydroxytetracycline, and 12-α-deoxytetracycline. The influence of environmental conditions upon the degradation of tetracycline was investigated. A nonantibacterial, nonfluorescent product was located from the degradation of 14C 5-hydroxytetracycline. Evidence indicated that neither the A nor D ring of 5-hydroxytetracycline is attacked. Acetone powders, lyophilized powders, and cell-free extracts exhibited a relatively limited substrate specificity compared to the washed cells.