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PubMed · 9675129

A sensitive, continuously recording fluorogenic assay for calpain.

S K Mallya·S Meyer·D Bozyczko-Coyne·R Siman·M A Ator
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Abstract

We have developed a sensitive and continuously recording fluorogenic assay for the thiol protease calpain. This assay uses the dipeptide substrate Suc-Leu-Tyr-4-Methoxy-2-Naphthylamine (Suc-LY-MNA) in Tris buffer (pH 7.5) in the presence of 0.1% CHAPS. The assay is linear over a wide range of enzyme concentration and is capable of detecting 10 picomolar calpain making it more sensitive than any previously published method. Moreover, this assay gives a rate that is linear for over ten minutes making it useful for mechanistic studies of inhibitors. This assay can be easily adapted to a 96-well plate format facilitating the large scale screening of inhibitors.

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CalpainCholic AcidsDetergentsDipeptidesEnzyme InhibitorsErythrocytesFluorometryHumansKineticsNaphthalenesRecombinant ProteinsSensitivity and SpecificitySubstrate SpecificityJournal ArticleResearch Support, Non-U.S. Gov't

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S K Mallya, S Meyer, D Bozyczko-Coyne, R Siman, M A Ator. 1998-07-20. A sensitive, continuously recording fluorogenic assay for calpain.. https://doi.org/10.1006/bbrc.1998.8952

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