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  1. Article ; Online: Minimum Free Energy Pathways of Reactive Processes with Nudged Elastic Bands.

    Semelak, Jonathan A / Zeida, Ari / Foglia, Nicolás O / Estrin, Darío A

    Journal of chemical theory and computation

    2023  Volume 19, Issue 18, Page(s) 6273–6293

    Abstract: The determination of minimum free energy pathways (MFEP) is one of the most widely used strategies to study reactive processes. For chemical reactions in complex environments, the combination of quantum mechanics (QM) with a molecular mechanics (MM) ... ...

    Abstract The determination of minimum free energy pathways (MFEP) is one of the most widely used strategies to study reactive processes. For chemical reactions in complex environments, the combination of quantum mechanics (QM) with a molecular mechanics (MM) representation is usually necessary in a hybrid QM/MM framework. However, even within the QM/MM approximation, the affordable sampling of the phase space is, in general, quite restricted. To reduce drastically the computational cost of the simulations, several methods such as umbrella sampling require performing a priori a selection of a reaction coordinate. The quality of the computed results, in an affordable computational time, is intimately related to the reaction coordinate election which is, in general, a nontrivial task. In this work, we provide an approach to model reactive processes in complex environments that does not require the a priori selection of a reaction coordinate. The proposed methodology combines QM/MM simulations with an extrapolation of the nudged elastic bands (NEB) method to the free energy surface (FENEB). We present and apply our own FENEB scheme to optimize MFEP in different reactive processes, using QM/MM frameworks at semiempirical and density functional theory levels. Our implementation is based on performing the FENEB optimization by uncoupling the optimization of the band in a perpendicular and tangential direction. In each step, a full optimization with the spring force is performed, which guarantees that the images remain evenly distributed. The robustness of the method and the influence of sampling on the quality of the optimized MFEP and its associated free energy barrier are studied. We show that the FENEB method provides a good estimation of the reaction barrier even with relatively short simulation times, supporting that its combination with QM/MM frameworks provides an adequate tool to study chemical processes in complex environments.
    Language English
    Publishing date 2023-08-30
    Publishing country United States
    Document type Journal Article
    ISSN 1549-9626
    ISSN (online) 1549-9626
    DOI 10.1021/acs.jctc.3c00366
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: The superoxide radical switch in the biology of nitric oxide and peroxynitrite.

    Piacenza, Lucía / Zeida, Ari / Trujillo, Madia / Radi, Rafael

    Physiological reviews

    2022  Volume 102, Issue 4, Page(s) 1881–1906

    Abstract: The free radical nitric oxide ( ...

    Abstract The free radical nitric oxide (
    MeSH term(s) Biology ; Humans ; Nitric Oxide/metabolism ; Peroxynitrous Acid/metabolism ; Superoxides
    Chemical Substances Superoxides (11062-77-4) ; Peroxynitrous Acid (14691-52-2) ; Nitric Oxide (31C4KY9ESH)
    Language English
    Publishing date 2022-05-23
    Publishing country United States
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ZDB-ID 209902-0
    ISSN 1522-1210 ; 0031-9333
    ISSN (online) 1522-1210
    ISSN 0031-9333
    DOI 10.1152/physrev.00005.2022
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Catalytic Mechanism of

    Sastre, Santiago / Manta, Bruno / Semelak, Jonathan A / Estrin, Dario / Trujillo, Madia / Radi, Rafael / Zeida, Ari

    Biochemistry

    2024  Volume 63, Issue 4, Page(s) 533–544

    Abstract: The oxidation of Met to methionine sulfoxide (MetSO) by oxidants such as hydrogen peroxide, hypochlorite, or peroxynitrite has profound effects on protein function. This modification can be reversed by methionine sulfoxide reductases (msr). In the ... ...

    Abstract The oxidation of Met to methionine sulfoxide (MetSO) by oxidants such as hydrogen peroxide, hypochlorite, or peroxynitrite has profound effects on protein function. This modification can be reversed by methionine sulfoxide reductases (msr). In the context of pathogen infection, the reduction of oxidized proteins gains significance due to microbial oxidative damage generated by the immune system. For example,
    MeSH term(s) Methionine Sulfoxide Reductases/metabolism ; Mycobacterium tuberculosis/metabolism ; Oxidation-Reduction ; Catalysis ; Oxidative Stress ; Methionine/metabolism
    Chemical Substances Methionine Sulfoxide Reductases (EC 1.8.4.-) ; Methionine (AE28F7PNPL)
    Language English
    Publishing date 2024-01-29
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1108-3
    ISSN 1520-4995 ; 0006-2960
    ISSN (online) 1520-4995
    ISSN 0006-2960
    DOI 10.1021/acs.biochem.3c00504
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Novel Lennard-Jones Parameters for Cysteine and Selenocysteine in the AMBER Force Field.

    Pedron, Federico N / Messias, Andresa / Zeida, Ari / Roitberg, Adrián E / Estrin, Darío A

    Journal of chemical information and modeling

    2023  Volume 63, Issue 2, Page(s) 595–604

    Abstract: Cysteine is a common amino acid with a thiol group that plays a pivotal role in a variety of scenarios in redox biochemistry. In contrast, selenocysteine, the 21st amino acid, is only present in 25 human proteins. Classical force-field parameters for ... ...

    Abstract Cysteine is a common amino acid with a thiol group that plays a pivotal role in a variety of scenarios in redox biochemistry. In contrast, selenocysteine, the 21st amino acid, is only present in 25 human proteins. Classical force-field parameters for cysteine and selenocysteine are still scarce. In this context, we present a methodology to obtain Lennard-Jones parameters for cysteine and selenocysteine in different physiologically relevant oxidation and protonation states. The new force field parameters obtained in this work are available at https://github.com/MALBECC/AMBER-parameters-database. The parameters were adjusted to reproduce water radial distribution functions obtained by density functional theory ab initio molecular dynamics. We validated the results by evaluating the impact of the choice of parameters on the structure and dynamics in classical molecular dynamics simulations of representative proteins containing catalytic cysteine/selenocysteine residues. There are significant changes in protein structure and dynamics depending on the parameters choice, specifically affecting the residues close to the catalytic sites.
    MeSH term(s) Humans ; Cysteine ; Selenocysteine ; Amino Acids/chemistry ; Proteins/chemistry ; Molecular Dynamics Simulation
    Chemical Substances Cysteine (K848JZ4886) ; Selenocysteine (0CH9049VIS) ; Amino Acids ; Proteins
    Language English
    Publishing date 2023-01-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 190019-5
    ISSN 1549-960X ; 0095-2338
    ISSN (online) 1549-960X
    ISSN 0095-2338
    DOI 10.1021/acs.jcim.2c01104
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Revisiting the role of 3-nitrotyrosine residues in the formation of alpha-synuclein oligomers and fibrils.

    Chavarría, Cecilia / Ivagnes, Rodrigo / Zeida, Ari / Piñeyro, María Dolores / Souza, José M

    Archives of biochemistry and biophysics

    2023  Volume 752, Page(s) 109858

    Abstract: Nitration of tyrosine residues in alpha-synuclein (a-syn) has been detected in different synucleinopathies, including Parkinson's disease. The potential role of 3-nitrotyrosine formation in a-syn, as an oxidative post-translational modification, is still ...

    Abstract Nitration of tyrosine residues in alpha-synuclein (a-syn) has been detected in different synucleinopathies, including Parkinson's disease. The potential role of 3-nitrotyrosine formation in a-syn, as an oxidative post-translational modification, is still elusive. In this work, we generated well-characterized tyrosine nitrated a-syn monomers and studied their capability to form oligomers and fibrils. We constructed tyrosine to phenylalanine mutants, containing a single tyrosine residue, a-syn mutant Y(125/133/136)F and Y(39/125/133)F) and assessed the impact in a-syn biophysical properties. Nitrated wild-type a-syn and the Y-F mutants, with one 3-nitrotyrosine residue in either the protein's N-terminal or C-terminal region, showed inhibition of fibril formation but retained the capacity of oligomer formation. The inhibition of a-syn fibrillation occurs even when an important amount of unmodified a-syn is still present. We characterized oligomers from both nitrated and non-nitrated forms of the wild-type protein and the mutant forms obtained. Our results indicate that the formation of 3-nitrotyrosine in a-syn could induce an off-pathway oligomer formation which may have an important impact in the development of synucleinopathies.
    MeSH term(s) Humans ; alpha-Synuclein/metabolism ; Nitrates/metabolism ; Parkinson Disease/metabolism ; Synucleinopathies ; Tyrosine/metabolism
    Chemical Substances 3-nitrotyrosine (3604-79-3) ; alpha-Synuclein ; Nitrates ; Tyrosine (42HK56048U) ; SNCA protein, human
    Language English
    Publishing date 2023-12-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 523-x
    ISSN 1096-0384 ; 0003-9861
    ISSN (online) 1096-0384
    ISSN 0003-9861
    DOI 10.1016/j.abb.2023.109858
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Mitochondrial Peroxiredoxin 3 Is Rapidly Oxidized and Hyperoxidized by Fatty Acid Hydroperoxides

    Cardozo, Giuliana / Mastrogiovanni, Mauricio / Zeida, Ari / Viera, Nicolás / Radi, Rafael / Reyes, Aníbal M. / Trujillo, Madia

    Antioxidants. 2023 Feb. 07, v. 12, no. 2

    2023  

    Abstract: Human peroxiredoxin 3 (HsPrx3) is a thiol-based peroxidase responsible for the reduction of most hydrogen peroxide and peroxynitrite formed in mitochondria. Mitochondrial disfunction can lead to membrane lipoperoxidation, resulting in the formation of ... ...

    Abstract Human peroxiredoxin 3 (HsPrx3) is a thiol-based peroxidase responsible for the reduction of most hydrogen peroxide and peroxynitrite formed in mitochondria. Mitochondrial disfunction can lead to membrane lipoperoxidation, resulting in the formation of lipid-bound fatty acid hydroperoxides (LFA-OOHs) which can be released to become free fatty acid hydroperoxides (fFA-OOHs). Herein, we report that HsPrx3 is oxidized and hyperoxidized by fFA-OOHs including those derived from arachidonic acid and eicosapentaenoic acid peroxidation at position 15 with remarkably high rate constants of oxidation (>3.5 × 10⁷ M⁻¹s⁻¹) and hyperoxidation (~2 × 10⁷ M⁻¹s⁻¹). The endoperoxide-hydroperoxide PGG₂, an intermediate in prostanoid synthesis, oxidized HsPrx3 with a similar rate constant, but was less effective in causing hyperoxidation. Biophysical methodologies suggest that HsPrx3 can bind hydrophobic structures. Indeed, molecular dynamic simulations allowed the identification of a hydrophobic patch near the enzyme active site that can allocate the hydroperoxide group of fFA-OOHs in close proximity to the thiolate in the peroxidatic cysteine. Simulations performed using available and herein reported kinetic data indicate that HsPrx3 should be considered a main target for mitochondrial fFA-OOHs. Finally, kinetic simulation analysis support that mitochondrial fFA-OOHs formation fluxes in the range of nM/s are expected to contribute to HsPrx3 hyperoxidation, a modification that has been detected in vivo under physiological and pathological conditions.
    Keywords active sites ; arachidonic acid ; cysteine ; eicosapentaenoic acid ; free fatty acids ; humans ; hydrogen peroxide ; hydrophobicity ; lipid peroxides ; mitochondria ; oxidation ; peroxidase ; peroxidation ; peroxiredoxin ; simulation models
    Language English
    Dates of publication 2023-0207
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article ; Online
    ZDB-ID 2704216-9
    ISSN 2076-3921
    ISSN 2076-3921
    DOI 10.3390/antiox12020408
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: In vivo observation of peroxiredoxins oligomerization dynamics.

    Zeida, Ari / Manta, Bruno / Trujillo, Madia

    Proceedings of the National Academy of Sciences of the United States of America

    2020  Volume 117, Issue 32, Page(s) 18918–18920

    MeSH term(s) Oxidation-Reduction ; Peroxiredoxins ; Protein Conformation
    Chemical Substances Peroxiredoxins (EC 1.11.1.15)
    Keywords covid19
    Language English
    Publishing date 2020-07-27
    Publishing country United States
    Document type Journal Article ; Comment
    ZDB-ID 209104-5
    ISSN 1091-6490 ; 0027-8424
    ISSN (online) 1091-6490
    ISSN 0027-8424
    DOI 10.1073/pnas.2012207117
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Mitochondrial Peroxiredoxin 3 Is Rapidly Oxidized and Hyperoxidized by Fatty Acid Hydroperoxides.

    Cardozo, Giuliana / Mastrogiovanni, Mauricio / Zeida, Ari / Viera, Nicolás / Radi, Rafael / Reyes, Aníbal M / Trujillo, Madia

    Antioxidants (Basel, Switzerland)

    2023  Volume 12, Issue 2

    Abstract: Human peroxiredoxin 3 ( ...

    Abstract Human peroxiredoxin 3 (
    Language English
    Publishing date 2023-02-07
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2704216-9
    ISSN 2076-3921
    ISSN 2076-3921
    DOI 10.3390/antiox12020408
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Mechanisms and consequences of protein cysteine oxidation: the role of the initial short-lived intermediates.

    Turell, Lucia / Zeida, Ari / Trujillo, Madia

    Essays in biochemistry

    2019  Volume 64, Issue 1, Page(s) 55–66

    Abstract: Thiol groups in protein cysteine (Cys) residues can undergo one- and two-electron oxidation reactions leading to the formation of thiyl radicals or sulfenic acids, respectively. In this mini-review we summarize the mechanisms and kinetics of the ... ...

    Abstract Thiol groups in protein cysteine (Cys) residues can undergo one- and two-electron oxidation reactions leading to the formation of thiyl radicals or sulfenic acids, respectively. In this mini-review we summarize the mechanisms and kinetics of the formation of these species by biologically relevant oxidants. Most of the latter react with the deprotonated form of the thiol. Since the pKa of the thiols in protein cysteines are usually close to physiological pH, the thermodynamics and the kinetics of their oxidation in vivo are affected by the acidity of the thiol. Moreover, the protein microenvironment has pronounced effects on cysteine residue reactivity, which in the case of the oxidation mediated by hydroperoxides, is known to confer specificity to particular protein cysteines. Despite their elusive nature, both thiyl radicals and sulfenic acids are involved in the catalytic mechanism of several enzymes and in the redox regulation of protein function and/or signaling pathways. They are usually short-lived species that undergo further reactions that converge in the formation of different stable products, resulting in several post-translational modifications of the protein. Some of these can be reversed through the action of specific cellular reduction systems. Others damage the proteins irreversibly, and can make them more prone to aggregation or degradation.
    MeSH term(s) Cysteine/chemistry ; Oxidation-Reduction ; Protein Processing, Post-Translational ; Proteins/chemistry ; Proteins/metabolism
    Chemical Substances Proteins ; Cysteine (K848JZ4886)
    Language English
    Publishing date 2019-12-27
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Review
    ISSN 1744-1358 ; 0071-1365
    ISSN (online) 1744-1358
    ISSN 0071-1365
    DOI 10.1042/EBC20190053
    Database MEDical Literature Analysis and Retrieval System OnLINE

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