Modifications induced by ascorbic acid on alkaline phosphatase fluorescence.

G E Martorana; E Meucci; G A Miggiano; A Mordente; A Ursitti; A Castelli

PubMed · 6511305

Modifications induced by ascorbic acid on alkaline phosphatase fluorescence.

G E Martorana·E Meucci·G A Miggiano·A Mordente·A Ursitti·A Castelli

Abstract

Ascorbic acid, isoascorbic acid and dehydroascorbic acid quench the tryptophyl fluorescence of alkaline phosphatase. The quenching is protein aspecific, although its extent reflects the different inhibitory efficiency of the compounds. The kinetic inactivation and emission deactivation of alkaline phosphatase isoenzymes present also striking similarities. The fluorescence modifications, moreover, show a particular pattern, indicative of a transition phenomenon. The quenching effects displayed by the ascorbic system on alkaline phosphatase can then supply an interesting insight into other aspects of the inhibitor-enzyme interaction.

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G E Martorana, E Meucci, G A Miggiano, A Mordente, A Ursitti, A Castelli. Modifications induced by ascorbic acid on alkaline phosphatase fluorescence.. https://pubmed.ncbi.nlm.nih.gov/6511305/

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