The Interaction of the Chemotherapeutic Drug Chlorambucil with Human Glutathione Transferase A1-1: Kinetic and Structural Analysis

dc.contributor.advisor	Karpusas, Michael	en
dc.contributor.advisor	Καρπούζας, Μιχαήλ	el
dc.contributor.author	Axarli, Irini	en
dc.contributor.author	Chiniadis, Lykourgos	en
dc.contributor.author	Papakyriakou, Athanasios	en
dc.contributor.author	Bethanis, Kostas	en
dc.contributor.author	Scopelitou, Katholiki	en
dc.contributor.author	Clonis, Yannis D.	en
dc.contributor.author	Labrou, Nikolaos E.	en
dc.contributor.author	Αξαρλή, Ειρήνη	el
dc.contributor.author	Χινιάδης, Λυκούργος	el
dc.contributor.author	Παπακυριακού, Αθανάσιος	el
dc.contributor.author	Μπεθάνης, Κώστας	el
dc.contributor.author	Σκοπελίτου, Καθολική	el
dc.contributor.author	Κλώνης, Ιωάννης Δ.	el
dc.contributor.author	Λάμπρου, Νικόλαος Ε.	el
dc.date.accessioned	2014-06-06T06:52:53Z
dc.date.available	2014-06-06T06:52:53Z
dc.date.issued	2013-02-27	en
dc.identifier.issn	19326203	en
dc.identifier.uri	http://dx.doi.org/10.1371/journal.pone.0056337	en
dc.identifier.uri	http://62.217.125.90/xmlui/handle/123456789/6234
dc.rights	CC0 1.0 Παγκόσμια	el
dc.rights.uri	http://creativecommons.org/publicdomain/zero/1.0/	en
dc.title	The Interaction of the Chemotherapeutic Drug Chlorambucil with Human Glutathione Transferase A1-1: Kinetic and Structural Analysis	en
heal.type	journalArticle	en
heal.identifier.primary	10.1371/journal.pone.0056337	en
heal.identifier.secondary	e56337	en
heal.recordProvider	Γεωπονικό Πανεπιστήμιο Αθηνών/Επιστήμη Γεωπονικής Βιοτεχνολογίας	el
heal.recordProvider	Ινστιτούτο "Δημόκριτος"	el
heal.publicationDate	2013-02-27	en
heal.bibliographicCitation	Karpusas, Michael. The Interaction of the Chemotherapeutic Drug Chlorambucil with Human Glutathione Transferase A1-1: Kinetic and Structural Analysis, PLoS One, vol. 8 (2), pp 1-11, PLOS, 2013	en
heal.abstract	Glutathione transferases (GSTs) are enzymes that contribute to cellular detoxification by catalysing the nucleophilic attack of glutathione (GSH) on the electrophilic centre of a number of xenobiotic compounds, including several chemotherapeutic drugs. In the present work we investigated the interaction of the chemotherapeutic drug chlorambucil (CBL) with human GSTA1-1 (hGSTA1-1) using kinetic analysis, protein crystallography and molecular dynamics. In the presence of GSH, CBL behaves as an efficient substrate for hGSTA1-1. The rate-limiting step of the catalytic reaction between CBL and GSH is viscosity-dependent and kinetic data suggest that product release is rate-limiting. The crystal structure of the hGSTA1-1/CBL-GSH complex was solved at 2.1 Å resolution by molecular replacement. CBL is bound at the H-site attached to the thiol group of GSH, is partially ordered and exposed to the solvent, making specific interactions with the enzyme. Molecular dynamics simulations based on the crystal structure indicated high mobility of the CBL moiety and stabilization of the C-terminal helix due to the presence of the adduct. In the absence of GSH, CBL is shown to be an alkylating irreversible inhibitor for hGSTA1-1. Inactivation of the enzyme by CBL followed a biphasic pseudo-first-order saturation kinetics with approximately 1 mol of CBL per mol of dimeric enzyme being incorporated. Structural analysis suggested that the modifying residue is Cys112 which is located at the entrance of the H-site. The results are indicative of a structural communication between the subunits on the basis of mutually exclusive modification of Cys112, indicating that the two enzyme active sites are presumably coordinated. © 2013 Karpusas et al.	en
heal.publisher	Public Library of Science (PLoS)	en
heal.journalName	PLoS ONE	en
dc.identifier.doi	10.1371/journal.pone.0056337	en