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PubMed · 3771103

Fluorogenic substrates for chymotrypsin with new fluorescent markers.

G Kokotos·C Tzougraki
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Abstract

Several substrates for chymotrypsin Glt-Phe-NHRx have been synthesized, where RxNH2 are the compounds 3-aminocoumarin (2), 6-aminocoumarin (3), 3-acetamido-6-aminocoumarin (4), 3-acetamido-8-aminocoumarin (5), 7-amino-4-methyl-2-quinolinone (AMQ), (6). The fluorescence properties of the new substrates and those of the corresponding free amines were examined. The compound 7-glutarylphenylalaninamido-4-methyl-2-quinolinone (Glt-Phe-AMQ), (15), provided a new suitable substrate for chymotrypsin determination. The enzymatic release of the fluorophore AMQ was measured at lambda ex = 360 nm and lambda em = 435 nm. The Km of 15 was 0.5 mM and its kcat/Km ratio was 47 M-1 s-1. By using this substrate, the detection limit of chymotrypsin was 10 ng/ml.

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ChymotrypsinFluorescent DyesHydrolysisSpectrometry, FluorescenceStructure-Activity RelationshipSubstrate SpecificityJournal Article

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BibTeXRIS

G Kokotos, C Tzougraki. 1986. Fluorogenic substrates for chymotrypsin with new fluorescent markers.. https://doi.org/10.1111/j.1399-3011.1986.tb03246.x

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