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Yoshimura M, Teramoto T, Asano H, Iwamoto Y, Kondo M, Nishimoto E, Kakuta Y. Crystal structure of tick tyrosylprotein sulfotransferase reveals the activation mechanism of the tick anticoagulant protein madanin. J Biol Chem 2024; 300:105748. [PMID: 38354785 PMCID: PMC10951654 DOI: 10.1016/j.jbc.2024.105748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/19/2024] [Accepted: 02/07/2024] [Indexed: 02/16/2024] Open
Abstract
Ticks pose a substantial public health risk as they transmit various pathogens. This concern is related to the adept blood-sucking strategy of ticks, underscored by the action of the anticoagulant, madanin, which is known to exhibit an approximately 1000-fold increase in anticoagulant activity following sulfation of its two tyrosine residues, Tyr51 and Tyr54. Despite this knowledge, the molecular mechanism underlying sulfation by tick tyrosylprotein sulfotransferase (TPST) remains unclear. In this study, we successfully prepared tick TPST as a soluble recombinant enzyme. We clarified the method by which this enzyme proficiently sulfates tyrosine residues in madanin. Biochemical analysis using a substrate peptide based on madanin and tick TPST, along with the analysis of the crystal structure of the complex and docking simulations, revealed a sequential sulfation process. Initial sulfation at the Tyr51 site augments binding, thereby facilitating efficient sulfation at Tyr54. Beyond direct biochemical implications, these findings considerably improve our understanding of tick blood-sucking strategies. Furthermore, combined with the utility of modified tick TPST, our findings may lead to the development of novel anticoagulants, promising avenues for thrombotic disease intervention and advancements in the field of public health.
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Affiliation(s)
- Misa Yoshimura
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan
| | - Takamasa Teramoto
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan.
| | - Hirai Asano
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan
| | - Yuka Iwamoto
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan
| | - Mariko Kondo
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan
| | - Etsuko Nishimoto
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan
| | - Yoshimitsu Kakuta
- Faculty of Agriculture, Laboratory of Biophysical Chemistry, Department of Bioscience and Biotechnology, Kyushu University, Fukuoka, Japan.
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2
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Mattioli EJ, Rossi J, Meloni M, De Mia M, Marchand CH, Tagliani A, Fanti S, Falini G, Trost P, Lemaire SD, Fermani S, Calvaresi M, Zaffagnini M. Structural snapshots of nitrosoglutathione binding and reactivity underlying S-nitrosylation of photosynthetic GAPDH. Redox Biol 2022; 54:102387. [PMID: 35793584 PMCID: PMC9287727 DOI: 10.1016/j.redox.2022.102387] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 06/25/2022] [Indexed: 10/30/2022] Open
Abstract
S-nitrosylation is a redox post-translational modification widely recognized to play an important role in cellular signaling as it can modulate protein function and conformation. At the physiological level, nitrosoglutathione (GSNO) is considered the major physiological NO-releasing compound due to its ability to transfer the NO moiety to protein thiols but the structural determinants regulating its redox specificity are not fully elucidated. In this study, we employed photosynthetic glyceraldehyde-3-phosphate dehydrogenase from Chlamydomonas reinhardtii (CrGAPA) to investigate the molecular mechanisms underlying GSNO-dependent thiol oxidation. We first observed that GSNO causes reversible enzyme inhibition by inducing S-nitrosylation. While the cofactor NADP+ partially protects the enzyme from GSNO-mediated S-nitrosylation, protein inhibition is not observed in the presence of the substrate 1,3-bisphosphoglycerate, indicating that the S-nitrosylation of the catalytic Cys149 is responsible for CrGAPA inactivation. The crystal structures of CrGAPA in complex with NADP+ and NAD+ reveal a general structural similarity with other photosynthetic GAPDH. Starting from the 3D structure, we carried out molecular dynamics simulations to identify the protein residues involved in GSNO binding. The reaction mechanism of GSNO with CrGAPA Cys149 was investigated by quantum mechanical/molecular mechanical calculations, which permitted to disclose the relative contribution of protein residues in modulating the activation barrier of the trans-nitrosylation reaction. Based on our findings, we provide functional and structural insights into the response of CrGAPA to GSNO-dependent regulation, possibly expanding the mechanistic features to other protein cysteines susceptible to be oxidatively modified by GSNO.
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Affiliation(s)
- Edoardo Jun Mattioli
- Department of Chemistry "G. Ciamician", University of Bologna, I-40126, Bologna, Italy
| | - Jacopo Rossi
- Department of Pharmacy and Biotechnologies, University of Bologna, I-40126, Bologna, Italy
| | - Maria Meloni
- Department of Pharmacy and Biotechnologies, University of Bologna, I-40126, Bologna, Italy
| | - Marcello De Mia
- CNRS, Sorbonne Université, Institut de Biologie Physico-Chimique, UMR8226, F-75005, Paris, France
| | - Christophe H Marchand
- CNRS, Sorbonne Université, Institut de Biologie Physico-Chimique, UMR8226, F-75005, Paris, France; CNRS, Institut de Biologie Physico-Chimique, Plateforme de Protéomique, FR550, F-75005, Paris, France
| | - Andrea Tagliani
- Department of Pharmacy and Biotechnologies, University of Bologna, I-40126, Bologna, Italy; CNRS, Sorbonne Université, Institut de Biologie Physico-Chimique, UMR8226, F-75005, Paris, France
| | - Silvia Fanti
- Department of Chemistry "G. Ciamician", University of Bologna, I-40126, Bologna, Italy
| | - Giuseppe Falini
- Department of Chemistry "G. Ciamician", University of Bologna, I-40126, Bologna, Italy
| | - Paolo Trost
- Department of Pharmacy and Biotechnologies, University of Bologna, I-40126, Bologna, Italy
| | - Stéphane D Lemaire
- CNRS, Sorbonne Université, Institut de Biologie Physico-Chimique, UMR8226, F-75005, Paris, France; Sorbonne Université, CNRS, Institut de Biologie Paris-Seine, Laboratory of Computational and Quantitative Biology, UMR7238, F-75005, Paris, France
| | - Simona Fermani
- Department of Chemistry "G. Ciamician", University of Bologna, I-40126, Bologna, Italy; CIRI Health Sciences & Technologies (HST), University of Bologna, I-40064, Bologna, Italy.
| | - Matteo Calvaresi
- Department of Chemistry "G. Ciamician", University of Bologna, I-40126, Bologna, Italy; CIRI Health Sciences & Technologies (HST), University of Bologna, I-40064, Bologna, Italy.
| | - Mirko Zaffagnini
- Department of Pharmacy and Biotechnologies, University of Bologna, I-40126, Bologna, Italy.
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3
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Guo YJ, Liu YJ. QM/MM study on enzymatic mechanism in sinigrin biosynthesis. CHINESE J CHEM PHYS 2022. [DOI: 10.1063/1674-0068/cjcp2111250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
As the major and abundant type of glucosinolates (GL) in plants, sinigrin has potential functions in promoting health and insect defense. The final step in the biosynthesis of sinigrin core structure is highly representative in GL compounds, which corresponds to the process from 3-methylthiopropyl ds-GL to 3-methylthiopropyl GL catalyzed by sulfotransferase (SOT). However, due to the lack of the crystallographic structure of SOT complexed with the 3-methylthiopropyl GL, little is known about this sulfonation process. Fortunately, the crystal structure of SOT 18 from Arabidopsis thaliana (AtSOT18) containing the substance (sinigrin) similar to 3-methylthiopropyl GL has been determined. To understand the enzymatic mechanism, we employed molecular dynamics (MD) simulation and quantum mechanics combined with molecular mechanics (QM/MM) methods to study the conversion from ds-sinigrin to sinigrin catalyzed by AtSOT18. The calculated results demonstrate that the reaction occurs through a concerted dissociative mechanism. Moreover, Lys93, Thr96, Thr97, Tyr130, His155, and two enzyme peptide chains (Pro92-Lys93 and Gln95-Thr96-Thr97) play a role in positioning the substrates and promoting the catalytic reaction by stabilizing the transition state geometry. Particularly, His155 acts as a catalytic base while Lys93 acts as a catalytic acid in the reaction process. The presently proposed concerted dissociative mechanism explains the role of AtSOT18 in sinigrin biosynthesis, and could be instructive for the study of GL biosynthesis catalyzed by other SOTs.
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Affiliation(s)
- Ya-Jie Guo
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Ya-Jun Liu
- Key Laboratory of Theoretical and Computational Photochemistry, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
- Center for Advanced Materials Research, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai 519087, China
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Šmak P, Tvaroška I, Koča J. The catalytic reaction mechanism of tyrosylprotein sulfotransferase-1. Phys Chem Chem Phys 2021; 23:23850-23860. [PMID: 34647946 DOI: 10.1039/d1cp03718h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tyrosine sulfation alters the biological activity of many proteins involved in different physiological and pathophysiological conditions, such as non-specific immune reaction, response to inflammation and ischemia, targeting of leukocytes and stem cells, or the formation of cancer metastases. Tyrosine sulfation is catalyzed by the enzymes tyrosylprotein sulfotransferases (TPST). In this study, we used QM/MM Car-Parrinello metadynamics simulations together with QM/MM potential energy calculations to investigate the catalytic mechanism of isoform TPST-1. The structural changes along the reaction coordinate are analyzed and discussed. Furthermore, both the methods supported the SN2 type of catalytic mechanism. The reaction barrier obtained from CPMD metadynamics was 12.8 kcal mol-1, and the potential energy scan led to reaction barriers of 11.6 kcal mol-1 and 13.7 kcal mol-1 with the B3LYP and OPBE functional, respectively. The comparison of the two methods (metadynamics and potential energy scan) may be helpful for future mechanistic studies. The insight into the reaction mechanism of TPST-1 might help with the rational design of transition-state TPST inhibitors.
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Affiliation(s)
- Pavel Šmak
- National Center for Biomolecular Research (NCBR), Faculty of Science, Masaryk University, Brno, Czech Republic
| | - Igor Tvaroška
- National Center for Biomolecular Research (NCBR), Faculty of Science, Masaryk University, Brno, Czech Republic.,Institute of Chemistry, Slovak Academy of Sciences, Bratislava, Slovak Republic.
| | - Jaroslav Koča
- National Center for Biomolecular Research (NCBR), Faculty of Science, Masaryk University, Brno, Czech Republic.,Central European Institute of Technology (CEITEC), Masaryk University, Brno, Czech Republic
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Gesteira TF, Marforio TD, Mueller JW, Calvaresi M, Coulson-Thomas VJ. Structural Determinants of Substrate Recognition and Catalysis by Heparan Sulfate Sulfotransferases. ACS Catal 2021; 11:10974-10987. [PMID: 37799563 PMCID: PMC10550706 DOI: 10.1021/acscatal.1c03088] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Heparan sulfate (HS) and heparin contain imprinted "sulfation codes", which dictate their diverse physiological and pathological functions. A group of orchestrated biosynthetic enzymes cooperate in polymerizing and modifying HS chains. The biotechnological development of enzymes that can recreate this sulfation pattern on synthetic heparin is challenging, primarily due to the paucity of quantitative data for sulfotransferase enzymes. Herein, we identified critical structural characteristics that determine substrate specificity and shed light on the catalytic mechanism of sugar sulfation of two HS sulfotransferases, 2-O-sulfotransferase (HS2ST) and 6-O-sulfotransferase (HS6ST). Two sets of molecular clamps in HS2ST recognize appropriate substrates; these clamps flank the acceptor binding site on opposite sides. The hexuronic epimers, and not their puckers, have a critical influence on HS2ST selectivity. In contrast, HS6ST recognizes a broader range of substrates. This promiscuity is granted by a conserved tryptophan residue, W210, that positions the acceptor within the active site for catalysis by means of strong electrostatic interactions. Lysines K131 and K132 act in concert with a second tryptophan, W153, shedding water molecules from within the active site, thus providing HS6ST with a binding preference toward 2-O-sulfated substrates. QM/MM calculations provided valuable mechanistic insights into the catalytic process, identifying that the sulfation of both HS2ST and HS6ST follows a SN2-like mechanism. When they are taken together, our findings reveal the molecular basis of how these enzymes recognize different substrates and catalyze sugar sulfation, enabling the generation of enzymes that could create specific heparin epitopes.
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Affiliation(s)
| | - Tainah Dorina Marforio
- Dipartimento di Chimica "Giacomo Ciamician", Università di Bologna, Bologna 40126, Italy
| | - Jonathan Wolf Mueller
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham B15 2TT, U.K
| | - Matteo Calvaresi
- Dipartimento di Chimica "Giacomo Ciamician", Università di Bologna, Bologna 40126, Italy
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Tvaroška I, Selvaraj C, Koča J. Selectins-The Two Dr. Jekyll and Mr. Hyde Faces of Adhesion Molecules-A Review. Molecules 2020; 25:molecules25122835. [PMID: 32575485 PMCID: PMC7355470 DOI: 10.3390/molecules25122835] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/27/2020] [Accepted: 06/17/2020] [Indexed: 02/06/2023] Open
Abstract
Selectins belong to a group of adhesion molecules that fulfill an essential role in immune and inflammatory responses and tissue healing. Selectins are glycoproteins that decode the information carried by glycan structures, and non-covalent interactions of selectins with these glycan structures mediate biological processes. The sialylated and fucosylated tetrasaccharide sLex is an essential glycan recognized by selectins. Several glycosyltransferases are responsible for the biosynthesis of the sLex tetrasaccharide. Selectins are involved in a sequence of interactions of circulated leukocytes with endothelial cells in the blood called the adhesion cascade. Recently, it has become evident that cancer cells utilize a similar adhesion cascade to promote metastases. However, like Dr. Jekyll and Mr. Hyde’s two faces, selectins also contribute to tissue destruction during some infections and inflammatory diseases. The most prominent function of selectins is associated with the initial stage of the leukocyte adhesion cascade, in which selectin binding enables tethering and rolling. The first adhesive event occurs through specific non-covalent interactions between selectins and their ligands, with glycans functioning as an interface between leukocytes or cancer cells and the endothelium. Targeting these interactions remains a principal strategy aimed at developing new therapies for the treatment of immune and inflammatory disorders and cancer. In this review, we will survey the significant contributions to and the current status of the understanding of the structure of selectins and the role of selectins in various biological processes. The potential of selectins and their ligands as therapeutic targets in chronic and acute inflammatory diseases and cancer will also be discussed. We will emphasize the structural characteristic of selectins and the catalytic mechanisms of glycosyltransferases involved in the biosynthesis of glycan recognition determinants. Furthermore, recent achievements in the synthesis of selectin inhibitors will be reviewed with a focus on the various strategies used for the development of glycosyltransferase inhibitors, including substrate analog inhibitors and transition state analog inhibitors, which are based on knowledge of the catalytic mechanism.
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Affiliation(s)
- Igor Tvaroška
- Central European Institute of Technology (CEITEC), Masaryk University, 62500 Brno, Czech Republic
- Institute of Chemistry, Slovak Academy of Sciences, 84538 Bratislava, Slovak Republic
- Correspondence: (I.T.); (J.K.); Tel.: +421-948-535-601 (I.T.); +420-731-682-606 (J.K.)
| | - Chandrabose Selvaraj
- Central European Institute of Technology (CEITEC), Masaryk University, 62500 Brno, Czech Republic
| | - Jaroslav Koča
- Central European Institute of Technology (CEITEC), Masaryk University, 62500 Brno, Czech Republic
- National Centre for Biomolecular Research, Faculty of Science, Masaryk University, 62500 Brno, Czech Republic
- Correspondence: (I.T.); (J.K.); Tel.: +421-948-535-601 (I.T.); +420-731-682-606 (J.K.)
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7
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Mattioli EJ, Bottoni A, Calvaresi M. DNAzymes at Work: A DFT Computational Investigation on the Mechanism of 9DB1. J Chem Inf Model 2019; 59:1547-1553. [DOI: 10.1021/acs.jcim.8b00815] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Edoardo Jun Mattioli
- Dipartimento di Chimica “G. Ciamician”, Alma Mater Studiorum - Università di Bologna, V. F. Selmi 2, 40126 Bologna, Italy
| | - Andrea Bottoni
- Dipartimento di Chimica “G. Ciamician”, Alma Mater Studiorum - Università di Bologna, V. F. Selmi 2, 40126 Bologna, Italy
| | - Matteo Calvaresi
- Dipartimento di Chimica “G. Ciamician”, Alma Mater Studiorum - Università di Bologna, V. F. Selmi 2, 40126 Bologna, Italy
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8
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Campesato L, Marforio TD, Giacinto P, Calvaresi M, Bottoni A. A Full QM Computational Study of the Catalytic Mechanism of α-1,4-Glucan Lyases. Chemphyschem 2018; 19:1514-1521. [DOI: 10.1002/cphc.201701332] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Indexed: 12/16/2022]
Affiliation(s)
- Lara Campesato
- Dipartimento di Chimica “Giacomo Ciamician”; Alma Mater Studiorum - Università di Bologna; via Francesco Selmi 2 40126 Bologna Italy
| | - Tainah Dorina Marforio
- Dipartimento di Chimica “Giacomo Ciamician”; Alma Mater Studiorum - Università di Bologna; via Francesco Selmi 2 40126 Bologna Italy
| | - Pietro Giacinto
- Dipartimento di Chimica “Giacomo Ciamician”; Alma Mater Studiorum - Università di Bologna; via Francesco Selmi 2 40126 Bologna Italy
| | - Matteo Calvaresi
- Dipartimento di Chimica “Giacomo Ciamician”; Alma Mater Studiorum - Università di Bologna; via Francesco Selmi 2 40126 Bologna Italy
| | - Andrea Bottoni
- Dipartimento di Chimica “Giacomo Ciamician”; Alma Mater Studiorum - Università di Bologna; via Francesco Selmi 2 40126 Bologna Italy
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9
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Taylor AB, Roberts KM, Cao X, Clark NE, Holloway SP, Donati E, Polcaro CM, Pica-Mattoccia L, Tarpley RS, McHardy SF, Cioli D, LoVerde PT, Fitzpatrick PF, Hart PJ. Structural and enzymatic insights into species-specific resistance to schistosome parasite drug therapy. J Biol Chem 2017; 292:11154-11164. [PMID: 28536265 PMCID: PMC5500785 DOI: 10.1074/jbc.m116.766527] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 05/17/2017] [Indexed: 02/05/2023] Open
Abstract
The antischistosomal prodrug oxamniquine is activated by a sulfotransferase (SULT) in the parasitic flatworm Schistosoma mansoni. Of the three main human schistosome species, only S. mansoni is sensitive to oxamniquine therapy despite the presence of SULT orthologs in Schistosoma hematobium and Schistosoma japonicum The reason for this species-specific drug action has remained a mystery for decades. Here we present the crystal structures of S. hematobium and S. japonicum SULTs, including S. hematobium SULT in complex with oxamniquine. We also examined the activity of the three enzymes in vitro; surprisingly, all three are active toward oxamniquine, yet we observed differences in catalytic efficiency that implicate kinetics as the determinant for species-specific toxicity. These results provide guidance for designing oxamniquine derivatives to treat infection caused by all species of schistosome to combat emerging resistance to current therapy.
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Affiliation(s)
- Alexander B Taylor
- From the Departments of Biochemistry and Structural Biology and
- the X-ray Crystallography Core Laboratory, University of Texas Health Science Center, San Antonio, Texas 78229
| | - Kenneth M Roberts
- Department of Chemistry and Physics, University of South Carolina, Aiken, South Carolina 29801
| | - Xiaohang Cao
- From the Departments of Biochemistry and Structural Biology and
| | | | | | - Enrica Donati
- Institute of Chemical Methodologies, Consiglio Nazionale delle Ricerche, Via Salaria Km 29.500, 00015 Monterotondo, Rome, Italy
| | - Chiara M Polcaro
- Institute of Chemical Methodologies, Consiglio Nazionale delle Ricerche, Via Salaria Km 29.500, 00015 Monterotondo, Rome, Italy
| | - Livia Pica-Mattoccia
- Institute of Cell Biology and Neurobiology, Consiglio Nazionale delle Ricerche, Via E. Ramarini 32, 00015 Monterotondo, Rome, Italy
| | - Reid S Tarpley
- Center for Innovative Drug Discovery, Department of Chemistry, University of Texas, San Antonio, Texas 78249, and
| | - Stanton F McHardy
- Center for Innovative Drug Discovery, Department of Chemistry, University of Texas, San Antonio, Texas 78249, and
| | - Donato Cioli
- Institute of Chemical Methodologies, Consiglio Nazionale delle Ricerche, Via Salaria Km 29.500, 00015 Monterotondo, Rome, Italy
| | - Philip T LoVerde
- From the Departments of Biochemistry and Structural Biology and
- Pathology and
| | | | - P John Hart
- From the Departments of Biochemistry and Structural Biology and
- the X-ray Crystallography Core Laboratory, University of Texas Health Science Center, San Antonio, Texas 78229
- Department of Veterans Affairs, South Texas Veterans Health Care System, San Antonio, Texas 78229
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10
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A mechanistic insights into manganese-catalyzed oxidative homocoupling reactions of Grignard reagents: A computational DFT investigation. J Organomet Chem 2016. [DOI: 10.1016/j.jorganchem.2016.04.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Ditchfield R, Spencer TA. Carbocation–π interaction: evaluation of the stabilization by phenylalanine of a biochemical carbocation intermediate. Org Biomol Chem 2016; 14:9543-9548. [DOI: 10.1039/c6ob01761d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Computational analyses, using primarily density functional theory, have been used to determine the stabilization associated with the carbocation–π interaction of a biochemical carbocation intermediate binding to a phenylalanine residue in an enzyme active site.
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Affiliation(s)
- Robert Ditchfield
- Department of Chemistry
- 6128 Burke Laboratory
- Dartmouth College
- Hanover
- USA
| | - Thomas A. Spencer
- Department of Chemistry
- 6128 Burke Laboratory
- Dartmouth College
- Hanover
- USA
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