A new fluorometric ultramicro determination of serum cystine aminopeptidase using an aminocoumarine derivative.
A rapid and sensitive fluorometric rate assay of serum cystine aminopeptidase is described using a novel fluorogenic substrate, 7-S-benzyl-L-cysteinyl-4-methylcoumarinylamide. The proposed method enabled us to determine cystine aminopeptidase activity in one minute using 10 microliter of serum. The assay was shown to be free from error due to the adsorption of the substrate to serum albumin. The values obtained by this method gave good correlation with those obtained by the conventional method of Watson [6].
D000626:Aminopeptidases / Q000097:blood*; D001322:Autoanalysis; D003374:Coumarins; D010122:Cystinyl Aminopeptidase / Q000097:blood*; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D008832:Microchemistry; D011247:Pregnancy; D013050:Spectrometry, Fluorescence
D003374:Coumarins; D005456:Fluorescent Dyes; C032125:7-benzylcysteinyl-4-methylcoumarinylamide; D000626:Aminopeptidases; D010122:Cystinyl Aminopeptidase