Intersite communication in dimeric enzymes highlighted by structural and thermodynamic analysis of didansyltyrosine binding to thymidylate synthases.

Autor: Venturelli A; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy., Guaitoli G; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy; Evotec SE, Biophysic - Essener Bogen 7, 22419 Hamburg, Germany., Vanossi D; Dipartimento di Scienze Chimiche e Geologiche, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy., Saitta F; Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, DeFENS, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy., Fessas D; Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, DeFENS, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy., Vitiello S; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy., Malpezzi G; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy; Clinical and Experimental Medicine (CEM) PhD Program, University of Modena and Reggio Emilia, Via G. Campi 287, 41125 Modena, Italy., Aiello D; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy., Ferrari S; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy., Tondi D; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy., Ponterini G; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy. Electronic address: glauco.ponterini@unimore.it., Paola Costi M; Dipartimento di Scienze della Vita, University of Modena and Reggio Emilia, Via Campi 103, 41125 Modena, Italy. Electronic address: mariapaola.costi@unimore.it.
Jazyk: angličtina
Zdroj: Bioorganic chemistry [Bioorg Chem] 2024 Oct; Vol. 151, pp. 107663. Date of Electronic Publication: 2024 Jul 20.
DOI: 10.1016/j.bioorg.2024.107663
Abstrakt: Intersite communication in dimeric enzymes, triggered by ligand binding, represents both a challenge and an opportunity in enzyme inhibition strategy. Though often understestimated, it can impact on the in vivo biological mechansim of an inhibitor and on its pharmacokinetics. Thymidylate synthase (TS) is a homodimeric enzyme present in almost all living organisms that plays a crucial role in DNA synthesis and cell replication. While its inhibition is a valid strategy in the therapy of several human cancers, designing specific inhibitors of bacterial TSs poses a challenge to the development of new anti-infective agents. N,O-didansyl-l-tyrosine (DDT) inhibits both Escherichia coli TS (EcTS) and Lactobacillus casei TS (LcTS). The available X-ray structure of the DDT:dUMP:EcTS ternary complex indicated an unexpected binding mode for DDT to EcTS, involving a rearrangement of the protein and addressing the matter of communication between the two active sites of an enzyme dimer. Combining molecular-level information on DDT binding to EcTS and LcTS extracted from structural and FRET-based fluorometric evidence with a thermodynamic characterization of these events obtained by fluorometric and calorimetric titrations, this study unveiled a negative cooperativity between the DDT bindings to the two monomers of each enzyme dimer. This result, complemented by the species-specific thermodynamic signatures of the binding events, implied that communication across the protein dimer was triggered by the first DDT binding. These findings could challenge the conventional understanding of TS inhibition and open the way for the development of novel TS inhibitors with a different mechanism of action and enhanced efficacy and specificity.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
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