Title
Inhibition of human glutathione S-transferase P1-1 by the flavonoid quercetin
Author
van Zanden, J.J.
Hamman, O.B.
van Iersel, M.L.P.S.
Boeren, S.
Cnubben, N.H.P.
Lo Bello, M.
Vervoort, J.
van Bladeren, P.J.
Rietjens, I.M.C.M.
Publication year
2003
Abstract
In the present study, the inhibition of human glutathione S-transferase P1-1 (GSTP1-1) by the flavonoid quercetin has been investigated. The results show a time- and concentration-dependent inhibition of GSTP1-1 by quercetin. GSTP1-1 activity is completely inhibited upon 1 h incubation with 100 μM quercetin or 2 h incubation with 25 μM quercetin, whereas 1 and 10 μM quercetin inhibit GSTP1-1 activity to a significant extent reaching a maximum of 25 and 42% inhibition respectively after 2 h. Co-incubation with tyrosinase greatly enhances the rate of inactivation, whereas co-incubation with ascorbic acid or glutathione prevents this inhibition. Addition of glutathione upon complete inactivation of GSTP1-1 partially restores the activity. Inhibition studies with the GSTP1-1 mutants C47S, C101S and the double mutant C47S/C101S showed that cysteine 47 is the key residue in the interaction between quercetin and GSTP1-1. HPLC and LC-MS analysis of trypsin digested GSTP1-1 inhibited by quercetin did not show formation of a covalent bond between Cys 47 residue of the peptide fragment 45-54 and quercetin. It was demonstrated that the inability to detect the covalent quercetin-peptide adduct using LC-MS is due to the reversible nature of the adduct-formation in combination with rapid and preferential dimerization of the peptide fragment once liberated from the protein. Nevertheless, the results of the present study indicate that quinone-type oxidation products of quercetin likely act as specific active site inhibitors of GSTP1-1 by binding to cysteine 47. © 2002 Elsevier Science Ireland Ltd. All rights reserved.
Subject
Biology
Physiological Sciences
Cysteine
Glutathione S-transferase
Inhibition
Quercetin
Quinone
ascorbic acid
cysteine
flavonoid
glutathione
glutathione transferase
isoenzyme
mutant protein
quercetin
article
chemical interaction
concentration response
covalent bond
dimerization
enzyme inhibition
human
incubation time
inhibition kinetics
time
Chromatography, High Pressure Liquid
Dose-Response Relationship, Drug
Glutathione Transferase
Humans
Mass Spectrometry
Molecular Structure
Monophenol Monooxygenase
Mutation
Quercetin
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http://resolver.tudelft.nl/uuid:69e13ac6-d389-469c-b5b1-2fdfe9bc08e9
DOI
https://doi.org/10.1016/s0009-2797(02)00250-8
TNO identifier
237083
ISSN
0009-2797
Source
Chemico-Biological Interactions, 145 (2), 139-148
Document type
article