Conversion of chloramphenicol degradation products by tyrosine aminotransferase from Flavobacteria.

The tyrosine aminotransferase of Flavobacterium strain CB 60, strain CB 6 and F. devorans r - a partially purified enzyme was used - is able to deaminate oxidatively p-aminophenylalanine and the intermediate products of chloramphenicol degradation p-nitrophenylserine and p-aminophenylserine. The aminotransferases of the strains CB 6 and CB 60 also convert p-aminophenylserinol. p-Nitrophenylserinol only reacts with the enzyme from strain CB 6. Determination of substrate specificity from strain CB 6 shows that an alcoholic group in C3 position (ring proximal) and to a lower degree an alcoholic group in C1 position (ring distal) decrease the turnover rate. Based on its broad substrate specificity the tyrosine aminotransferase has the ability not only to metabolize physiological compounds but also degradation products of chloramphenicol.