Enzymatic method of determining beta-lactam ring antibiotics.

摘要

It entails the following stages: 1) incubation of the biological fluid with the soluble D-alanyl-D-alanine carboxypeptidase produced by the strain Actinomadura R39; 2) incubation of the mixture obtained with a solution of substrate, which is a thioester of formula in the presence of an amino acid of D configuration or glycine; 3) determination of the quantity of 2-mercaptoalkanoic acid of formula formed in stage 2); 4) comparison of the determination of stage 3) with a standard. In these formulae:   R1 = benzoyl, phenylacetyl or Nalpha-acetyl-Llysyl,   R2 = glycyl or D-alanyl, and   R3 = H or CH3. The invention also relates to a test kit comprising the reagents to be employed for implementation of the method.