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A fluorogenic active-site titrant for serine proteases.

D P Green
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Abstract

The synthesis of 3'-(4-guanidinobenzoyloxy)-spiro(isobenzofuran-1(3H),9H-[9H]xan then]-3-one or 3HFGB, an active-site titrant for serine proteases, is described. 3HFGB has two advantages over previously described titrants. It is very sensitive (it can measure serine proteases at the 10(-11)-10(-12) M level), and it can be used at stoichiometric ratios of titrant to protease of unity or less. Moreover, the fluorogenic leaving group, 3'-hydroxyspiro[isobenzofuran-1(3H),9'-[9H]xanthen]-3- one, is suitable for use in a range of esteropeptidase substrates. The use of 3HFGB in the active-site titration of trypsin is described.

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Binding SitesEndopeptidasesFluorescenceGuanidinesSerine EndopeptidasesXanthinesJournal ArticleResearch Support, Non-U.S. Gov't

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D P Green. 1985. A fluorogenic active-site titrant for serine proteases.. https://doi.org/10.1016/0003-2697(85)90302-1

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