High-performance liquid chromatographic determination of four kinds of biotin-containing carboxylase

A convenient and reliable reversed-phase liquid chromatographic assay for four kinds of carboxylase, i.e. pyruvate carboxylase, acetyl-coenzyme A carboxylase, propionyl-coenzyme A carboxylase, and 3-methylcrotonyl-coenzyme A carboxylase, was developed. These are all biotin enzymes, which contain covalently bound biotin as a co-factor (co-enzyme). This chromatographic method, which is free from interferences, gives a stoichiometric and precise assay for these enzymes. It is non-radioisotopic, which makes it suitable for clinical laboratories. The assay time required for one sample is ca. 30 min. The method was satisfactorily applied to guinea-pig kidney homogenates after a simple pretreatment with acid.