1
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Yu J, Ramirez LM, Lin Q, Burz DS, Shekhtman A. Ribosome External Electric Field Regulates Metabolic Enzyme Activity: The RAMBO Effect. J Phys Chem B 2024; 128:7002-7021. [PMID: 39012038 DOI: 10.1021/acs.jpcb.4c00628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/17/2024]
Abstract
Ribosomes bind to many metabolic enzymes and change their activity. A general mechanism for ribosome-mediated amplification of metabolic enzyme activity, RAMBO, was formulated and elucidated for the glycolytic enzyme triosephosphate isomerase, TPI. The RAMBO effect results from a ribosome-dependent electric field-substrate dipole interaction energy that can increase or decrease the ground state of the reactant and product to regulate catalytic rates. NMR spectroscopy was used to determine the interaction surface of TPI binding to ribosomes and to measure the corresponding kinetic rates in the absence and presence of intact ribosome particles. Chemical cross-linking and mass spectrometry revealed potential ribosomal protein binding partners of TPI. Structural results and related changes in TPI energetics and activity show that the interaction between TPI and ribosomal protein L11 mediate the RAMBO effect.
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Affiliation(s)
- Jianchao Yu
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
| | - Lisa M Ramirez
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
| | - Qishan Lin
- RNA Epitranscriptomics & Proteomics Resource, University at Albany, State University of New York, Albany, New York 12222, United States
| | - David S Burz
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
| | - Alexander Shekhtman
- Department of Chemistry, University at Albany, State University of New York, Albany, New York 12222, United States
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2
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Rahimi M, Taghdir M, Abasi Joozdani F. Dynamozones are the most obvious sign of the evolution of conformational dynamics in HIV-1 protease. Sci Rep 2023; 13:14179. [PMID: 37648682 PMCID: PMC10469195 DOI: 10.1038/s41598-023-40818-x] [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: 02/21/2023] [Accepted: 08/17/2023] [Indexed: 09/01/2023] Open
Abstract
Proteins are not static but are flexible molecules that can adopt many different conformations. The HIV-1 protease is an important target for the development of therapies to treat AIDS, due to its critical role in the viral life cycle. We investigated several dynamics studies on the HIV-1 protease families to illustrate the significance of examining the dynamic behaviors and molecular motions for an entire understanding of their dynamics-structure-function relationships. Using computer simulations and principal component analysis approaches, the dynamics data obtained revealed that: (i) The flap regions are the most obvious sign of the evolution of conformational dynamics in HIV-1 protease; (ii) There are dynamic structural regions in some proteins that contribute to the biological function and allostery of proteins via appropriate flexibility. These regions are a clear sign of the evolution of conformational dynamics of proteins, which we call dynamozones. The flap regions are one of the most important dynamozones members that are critical for HIV-1 protease function. Due to the existence of other members of dynamozones in different proteins, we propose to consider dynamozones as a footprint of the evolution of the conformational dynamics of proteins.
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Affiliation(s)
- Mohammad Rahimi
- Department of Biophysics, Faculty of Biological Science, Tarbiat Modares University, Tehran, 14115_111, Iran
| | - Majid Taghdir
- Department of Biophysics, Faculty of Biological Science, Tarbiat Modares University, Tehran, 14115_111, Iran.
| | - Farzane Abasi Joozdani
- Department of Biophysics, Faculty of Biological Science, Tarbiat Modares University, Tehran, 14115_111, Iran
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3
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Romero-Rivera A, Corbella M, Parracino A, Patrick WM, Kamerlin SCL. Complex Loop Dynamics Underpin Activity, Specificity, and Evolvability in the (βα) 8 Barrel Enzymes of Histidine and Tryptophan Biosynthesis. JACS AU 2022; 2:943-960. [PMID: 35557756 PMCID: PMC9088769 DOI: 10.1021/jacsau.2c00063] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 05/16/2023]
Abstract
Enzymes are conformationally dynamic, and their dynamical properties play an important role in regulating their specificity and evolvability. In this context, substantial attention has been paid to the role of ligand-gated conformational changes in enzyme catalysis; however, such studies have focused on tremendously proficient enzymes such as triosephosphate isomerase and orotidine 5'-monophosphate decarboxylase, where the rapid (μs timescale) motion of a single loop dominates the transition between catalytically inactive and active conformations. In contrast, the (βα)8-barrels of tryptophan and histidine biosynthesis, such as the specialist isomerase enzymes HisA and TrpF, and the bifunctional isomerase PriA, are decorated by multiple long loops that undergo conformational transitions on the ms (or slower) timescale. Studying the interdependent motions of multiple slow loops, and their role in catalysis, poses a significant computational challenge. This work combines conventional and enhanced molecular dynamics simulations with empirical valence bond simulations to provide rich details of the conformational behavior of the catalytic loops in HisA, PriA, and TrpF, and the role of their plasticity in facilitating bifunctionality in PriA and evolved HisA variants. In addition, we demonstrate that, similar to other enzymes activated by ligand-gated conformational changes, loops 3 and 4 of HisA and PriA act as gripper loops, facilitating the isomerization of the large bulky substrate ProFAR, albeit now on much slower timescales. This hints at convergent evolution on these different (βα)8-barrel scaffolds. Finally, our work reemphasizes the potential of engineering loop dynamics as a tool to artificially manipulate the catalytic repertoire of TIM-barrel proteins.
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Affiliation(s)
- Adrian Romero-Rivera
- Department
of Chemistry—BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Marina Corbella
- Department
of Chemistry—BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Antonietta Parracino
- Department
of Chemistry—BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Wayne M. Patrick
- Centre
for Biodiscovery, School of Biological Sciences, Victoria University of Wellington, 6012 Wellington, New Zealand
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4
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Tessmer MH, DeCero SA, Del Alamo D, Riegert MO, Meiler J, Frank DW, Feix JB. Characterization of the ExoU activation mechanism using EPR and integrative modeling. Sci Rep 2020; 10:19700. [PMID: 33184362 PMCID: PMC7665212 DOI: 10.1038/s41598-020-76023-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 10/19/2020] [Indexed: 12/17/2022] Open
Abstract
ExoU, a type III secreted phospholipase effector of Pseudomonas aeruginosa, serves as a prototype to model large, dynamic, membrane-associated proteins. ExoU is synergistically activated by interactions with membrane lipids and ubiquitin. To dissect the activation mechanism, structural homology was used to identify an unstructured loop of approximately 20 residues in the ExoU amino acid sequence. Mutational analyses indicate the importance of specific loop amino acid residues in mediating catalytic activity. Engineered disulfide cross-links show that loop movement is required for activation. Site directed spin labeling EPR and DEER (double electron-electron resonance) studies of apo and holo states demonstrate local conformational changes at specific sites within the loop and a conformational shift of the loop during activation. These data are consistent with the formation of a substrate-binding pocket providing access to the catalytic site. DEER distance distributions were used as constraints in RosettaDEER to construct ensemble models of the loop in both apo and holo states, significantly extending the range for modeling a conformationally dynamic loop.
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Affiliation(s)
- Maxx H Tessmer
- Department of Chemistry, University of Washington, Seattle, WA, USA
| | - Samuel A DeCero
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Diego Del Alamo
- Department of Chemistry and Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, USA
| | - Molly O Riegert
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Jens Meiler
- Department of Chemistry and Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
- Institute for Drug Discovery, Leipzig University Medical School, Leipzig SAC, Germany
| | - Dara W Frank
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, USA.
| | - Jimmy B Feix
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI, USA
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5
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Sakhrani VV, Hilario E, Caulkins BG, Hatcher-Skeers ME, Fan L, Dunn MF, Mueller LJ. Backbone assignments and conformational dynamics in the S. typhimurium tryptophan synthase α-subunit from solution-state NMR. JOURNAL OF BIOMOLECULAR NMR 2020; 74:341-354. [PMID: 32415580 PMCID: PMC7451264 DOI: 10.1007/s10858-020-00320-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Accepted: 05/07/2020] [Indexed: 06/11/2023]
Abstract
Backbone assignments for the isolated α-subunit of Salmonella typhimurium tryptophan synthase (TS) are reported based on triple resonance solution-state NMR experiments on a uniformly 2H,13C,15N-labeled sample. From the backbone chemical shifts, secondary structure and random coil index order parameters (RCI-S2) are predicted. Titration with the 3-indole-D-glycerol 3'-phosphate analog, N-(4'-trifluoromethoxybenzenesulfonyl)-2-aminoethyl phosphate (F9), leads to chemical shift perturbations indicative of conformational changes from which an estimate of the dissociation constant is obtained. Comparisons of the backbone chemical-shifts, RCI-S2 values, and site-specific relaxation times with and without F9 reveal allosteric changes including modulation in secondary structures and loop rigidity induced upon ligand binding. A comparison is made to the X-ray crystal structure of the α-subunit in the full TS αββα bi-enzyme complex and to two new X-ray crystal structures of the isolated TS α-subunit reported in this work.
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Affiliation(s)
- Varun V Sakhrani
- Department of Chemistry, University of California Riverside, Riverside, CA, 92521, USA
| | - Eduardo Hilario
- Department of Chemistry, University of California Riverside, Riverside, CA, 92521, USA
| | - Bethany G Caulkins
- Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Mary E Hatcher-Skeers
- Keck Science Department, Claremont McKenna, Pitzer, and Scripps Colleges, Claremont, CA, 91711, USA
| | - Li Fan
- Department of Biochemistry, University of California Riverside, Riverside, CA, 92521, USA
| | - Michael F Dunn
- Department of Biochemistry, University of California Riverside, Riverside, CA, 92521, USA
| | - Leonard J Mueller
- Department of Chemistry, University of California Riverside, Riverside, CA, 92521, USA.
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6
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A computational study of the molecular basis of antibiotic resistance in a DXR mutant. J Comput Aided Mol Des 2019; 33:927-940. [DOI: 10.1007/s10822-019-00229-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 09/28/2019] [Indexed: 10/25/2022]
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7
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Seo DH, Jung JH, Park CS. Improved polymerization activity of Deinococcus geothermalis amylosucrase by semi-rational design: Effect of loop flexibility on the polymerization reaction. Int J Biol Macromol 2019; 130:177-185. [DOI: 10.1016/j.ijbiomac.2019.02.139] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 02/15/2019] [Accepted: 02/23/2019] [Indexed: 12/17/2022]
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8
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Zhai X, Reinhardt CJ, Malabanan MM, Amyes TL, Richard JP. Enzyme Architecture: Amino Acid Side-Chains That Function To Optimize the Basicity of the Active Site Glutamate of Triosephosphate Isomerase. J Am Chem Soc 2018; 140:8277-8286. [PMID: 29862813 PMCID: PMC6037162 DOI: 10.1021/jacs.8b04367] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
We report pH rate profiles for kcat and Km for the
isomerization reaction
of glyceraldehyde 3-phosphate catalyzed by wildtype triosephosphate
isomerase (TIM) from three organisms and by ten mutants of TIM; and,
for Ki for inhibition of this reaction
by phosphoglycolate trianion (I3–). The pH profiles for Ki show
that the binding of I3– to TIM (E) to form EH·I3– is accompanied by
uptake of a proton by the carboxylate side-chain of E165, whose function
is to abstract a proton from substrate. The complexes for several
mutants exist mainly as E–·I3– at high pH, in which cases the pH profiles define the pKa for deprotonation of EH·I3–. The linear
free energy correlation, with slope of 0.73 (r2 = 0.96), between kcat/Km for TIM-catalyzed isomerization and the disassociation
constant of PGA trianion for TIM shows that EH·I3– and the
transition state are stabilized by similar interactions with the protein
catalyst. Values of pKa = 10–10.5
were estimated for deprotonation of EH·I3– for wildtype TIM.
This pKa decreases to as low as 6.3 for
the severely crippled Y208F mutant. There is a correlation between
the effect of several mutations on kcat/Km and on pKa for EH·I3–. The results support a model where the strong basicity of
E165 at the complex to the enediolate reaction intermediate is promoted
by side-chains from Y208 and S211, which serve to clamp loop 6 over
the substrate; I170, which assists in the creation of a hydrophobic
environment for E165; and P166, which functions in driving the carboxylate
side-chain of E165 toward enzyme-bound substrate.
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Affiliation(s)
- Xiang Zhai
- Department of Chemistry , University at Buffalo, SUNY , Buffalo , New York 14260-3000 United States
| | - Christopher J Reinhardt
- Department of Chemistry , University of Illinois at Urbana-Champaign , 600 S Mathews Avenue , Urbana , Illinois 61801 , United States
| | - M Merced Malabanan
- Department of Biochemistry , Vanderbilt University , 842 Robinson Research Building , Nashville , Tennessee 37205 , United States
| | - Tina L Amyes
- Department of Chemistry , University at Buffalo, SUNY , Buffalo , New York 14260-3000 United States
| | - John P Richard
- Department of Chemistry , University at Buffalo, SUNY , Buffalo , New York 14260-3000 United States
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9
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Schlee S, Klein T, Schumacher M, Nazet J, Merkl R, Steinhoff HJ, Sterner R. Relationship of Catalysis and Active Site Loop Dynamics in the (βα)8-Barrel Enzyme Indole-3-glycerol Phosphate Synthase. Biochemistry 2018; 57:3265-3277. [DOI: 10.1021/acs.biochem.8b00167] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sandra Schlee
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Thomas Klein
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Magdalena Schumacher
- Department of Physics, University of Osnabrück, Barbarastrasse 7, D-49076 Osnabrück, Germany
| | - Julian Nazet
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Rainer Merkl
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
| | - Heinz-Jürgen Steinhoff
- Department of Physics, University of Osnabrück, Barbarastrasse 7, D-49076 Osnabrück, Germany
| | - Reinhard Sterner
- Institute of Biophysics and Physical Biochemistry, University of Regensburg, Universitätsstrasse 31, D-93053 Regensburg, Germany
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10
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Vázquez-Raygoza A, Cano-González L, Velázquez-Martínez I, Trejo-Soto PJ, Castillo R, Hernández-Campos A, Hernández-Luis F, Oria-Hernández J, Castillo-Villanueva A, Avitia-Domínguez C, Sierra-Campos E, Valdez-Solana M, Téllez-Valencia A. Species-Specific Inactivation of Triosephosphate Isomerase from Trypanosoma brucei: Kinetic and Molecular Dynamics Studies. Molecules 2017; 22:molecules22122055. [PMID: 29186784 PMCID: PMC6149853 DOI: 10.3390/molecules22122055] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 11/19/2017] [Accepted: 11/21/2017] [Indexed: 01/07/2023] Open
Abstract
Human African Trypanosomiasis (HAT), a disease that provokes 2184 new cases a year in Sub-Saharan Africa, is caused by Trypanosoma brucei. Current treatments are limited, highly toxic, and parasite strains resistant to them are emerging. Therefore, there is an urgency to find new drugs against HAT. In this context, T. brucei depends on glycolysis as the unique source for ATP supply; therefore, the enzyme triosephosphate isomerase (TIM) is an attractive target for drug design. In the present work, three new benzimidazole derivatives were found as TbTIM inactivators (compounds 1, 2 and 3) with an I50 value of 84, 82 and 73 µM, respectively. Kinetic analyses indicated that the three molecules were selective when tested against human TIM (HsTIM) activity. Additionally, to study their binding mode in TbTIM, we performed a 100 ns molecular dynamics simulation of TbTIM-inactivator complexes. Simulations showed that the binding of compounds disturbs the structure of the protein, affecting the conformations of important domains such as loop 6 and loop 8. In addition, the physicochemical and drug-like parameters showed by the three compounds suggest a good oral absorption. In conclusion, these molecules will serve as a guide to design more potent inactivators that could be used to obtain new drugs against HAT.
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Affiliation(s)
- Alejandra Vázquez-Raygoza
- Faculty of Medicine and Nutrition, Juarez University of Durango State, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (A.V.-R.); (C.A.-D.)
| | - Lucia Cano-González
- School of Chemistry, Pharmacy Department, National Autonomous University of Mexico, Mexico City 04510, Mexico; (L.C.-G.); (I.V.-M.); (P.J.T.-S.); (R.C.); (A.H.-C.); (F.H.-L.)
| | - Israel Velázquez-Martínez
- School of Chemistry, Pharmacy Department, National Autonomous University of Mexico, Mexico City 04510, Mexico; (L.C.-G.); (I.V.-M.); (P.J.T.-S.); (R.C.); (A.H.-C.); (F.H.-L.)
| | - Pedro Josué Trejo-Soto
- School of Chemistry, Pharmacy Department, National Autonomous University of Mexico, Mexico City 04510, Mexico; (L.C.-G.); (I.V.-M.); (P.J.T.-S.); (R.C.); (A.H.-C.); (F.H.-L.)
| | - Rafael Castillo
- School of Chemistry, Pharmacy Department, National Autonomous University of Mexico, Mexico City 04510, Mexico; (L.C.-G.); (I.V.-M.); (P.J.T.-S.); (R.C.); (A.H.-C.); (F.H.-L.)
| | - Alicia Hernández-Campos
- School of Chemistry, Pharmacy Department, National Autonomous University of Mexico, Mexico City 04510, Mexico; (L.C.-G.); (I.V.-M.); (P.J.T.-S.); (R.C.); (A.H.-C.); (F.H.-L.)
| | - Francisco Hernández-Luis
- School of Chemistry, Pharmacy Department, National Autonomous University of Mexico, Mexico City 04510, Mexico; (L.C.-G.); (I.V.-M.); (P.J.T.-S.); (R.C.); (A.H.-C.); (F.H.-L.)
| | - Jesús Oria-Hernández
- Biochemistry and Genetics Laboratory, National Institute of Pediatrics, Ministry of Health, Mexico City 04534, Mexico; (J.O.-H.); (A.C.-V.)
| | - Adriana Castillo-Villanueva
- Biochemistry and Genetics Laboratory, National Institute of Pediatrics, Ministry of Health, Mexico City 04534, Mexico; (J.O.-H.); (A.C.-V.)
| | - Claudia Avitia-Domínguez
- Faculty of Medicine and Nutrition, Juarez University of Durango State, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (A.V.-R.); (C.A.-D.)
| | - Erick Sierra-Campos
- Faculty of Chemical Sciences, Juarez University of Durango State, Av. Artículo 123 S/N Fracc. Filadelfia, Gomez Palacio, Durango 35010, Mexico; (E.S.-C.); (M.V.-S)
| | - Mónica Valdez-Solana
- Faculty of Chemical Sciences, Juarez University of Durango State, Av. Artículo 123 S/N Fracc. Filadelfia, Gomez Palacio, Durango 35010, Mexico; (E.S.-C.); (M.V.-S)
| | - Alfredo Téllez-Valencia
- Faculty of Medicine and Nutrition, Juarez University of Durango State, Av. Universidad y Fanny Anitua S/N, Durango 34000, Mexico; (A.V.-R.); (C.A.-D.)
- Correspondence: ; Tel./Fax: +52-618-812-1687
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11
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Olivares-Illana V, Riveros-Rosas H, Cabrera N, Tuena de Gómez-Puyou M, Pérez-Montfort R, Costas M, Gómez-Puyou A. A guide to the effects of a large portion of the residues of triosephosphate isomerase on catalysis, stability, druggability, and human disease. Proteins 2017; 85:1190-1211. [PMID: 28378917 DOI: 10.1002/prot.25299] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 03/14/2017] [Accepted: 03/27/2017] [Indexed: 12/11/2022]
Abstract
Triosephosphate isomerase (TIM) is a ubiquitous enzyme, which appeared early in evolution. TIM is responsible for obtaining net ATP from glycolysis and producing an extra pyruvate molecule for each glucose molecule, under aerobic and anaerobic conditions. It is placed in a metabolic crossroad that allows a quick balance of the triose phosphate aldolase produced by glycolysis, and is also linked to lipid metabolism through the alternation of glycerol-3-phosphate and the pentose cycle. TIM is one of the most studied enzymes with more than 199 structures deposited in the PDB. The interest for this enzyme stems from the fact that it is involved in glycolysis, but also in aging, human diseases and metabolism. TIM has been a target in the search for chemical compounds against infectious diseases and is a model to study catalytic features. Until February 2017, 62% of all residues of the protein have been studied by mutagenesis and/or using other approaches. Here, we present a detailed and comprehensive recompilation of the reported effects on TIM catalysis, stability, druggability and human disease produced by each of the amino acids studied, contributing to a better understanding of the properties of this fundamental protein. The information reviewed here shows that the role of the noncatalytic residues depend on their molecular context, the delicate balance between the short and long-range interactions in concerted action determining the properties of the protein. Each protein should be regarded as a unique entity that has evolved to be functional in the organism to which it belongs. Proteins 2017; 85:1190-1211. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Vanesa Olivares-Illana
- Laboratorio de Interacciones Biomoleculares y Cáncer. Instituto de Física, Universidad Autónoma de San Luis Potosí, SLP, 78290, México
| | - Hector Riveros-Rosas
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Nallely Cabrera
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Marietta Tuena de Gómez-Puyou
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Ruy Pérez-Montfort
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Miguel Costas
- Laboratorio de Biofisicoquímica, Departamento de Fisicoquímica, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
| | - Armando Gómez-Puyou
- Departamento de Bioquímica y Biología Estructural, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Ciudad de México, 04510, México
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12
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Heo S, Lee J, Joo K, Shin HC, Lee J. Protein Loop Structure Prediction Using Conformational Space Annealing. J Chem Inf Model 2017; 57:1068-1078. [DOI: 10.1021/acs.jcim.6b00742] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Seungryong Heo
- School
of Systems Biomedical Science, Soongsil University, Seoul 06978, Korea
| | - Juyong Lee
- Laboratory
of Computational Biology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, United States
| | | | - Hang-Cheol Shin
- School
of Systems Biomedical Science, Soongsil University, Seoul 06978, Korea
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13
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Controlling Active Site Loop Dynamics in the (β/α)8 Barrel Enzyme Indole-3-Glycerol Phosphate Synthase. Catalysts 2016. [DOI: 10.3390/catal6090129] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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14
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Papaleo E, Saladino G, Lambrughi M, Lindorff-Larsen K, Gervasio FL, Nussinov R. The Role of Protein Loops and Linkers in Conformational Dynamics and Allostery. Chem Rev 2016; 116:6391-423. [DOI: 10.1021/acs.chemrev.5b00623] [Citation(s) in RCA: 239] [Impact Index Per Article: 29.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Elena Papaleo
- Computational
Biology Laboratory, Unit of Statistics, Bioinformatics and Registry, Danish Cancer Society Research Center, Strandboulevarden 49, 2100 Copenhagen, Denmark
- Structural
Biology and NMR Laboratory, Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Giorgio Saladino
- Department
of Chemistry, University College London, London WC1E 6BT, United Kingdom
| | - Matteo Lambrughi
- Department
of Biotechnology and Biosciences, University of Milano-Bicocca, Piazza
della Scienza 2, 20126 Milan, Italy
| | - Kresten Lindorff-Larsen
- Structural
Biology and NMR Laboratory, Department of Biology, University of Copenhagen, 2200 Copenhagen, Denmark
| | | | - Ruth Nussinov
- Cancer
and Inflammation Program, Leidos Biomedical Research, Inc., Frederick
National Laboratory for Cancer Research, National Cancer Institute Frederick, Frederick, Maryland 21702, United States
- Sackler Institute
of Molecular Medicine, Department of Human Genetics and Molecular
Medicine Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
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15
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Zhai X, Amyes TL, Richard JP. Role of Loop-Clamping Side Chains in Catalysis by Triosephosphate Isomerase. J Am Chem Soc 2015; 137:15185-97. [PMID: 26570983 PMCID: PMC4694050 DOI: 10.1021/jacs.5b09328] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
The side chains of
Y208 and S211 from loop 7 of triosephosphate
isomerase (TIM) form hydrogen bonds to backbone amides and carbonyls
from loop 6 to stabilize the caged enzyme–substrate complex.
The effect of seven mutations [Y208T, Y208S, Y208A, Y208F, S211G,
S211A, Y208T/S211G] on the kinetic parameters for TIM catalyzed reactions
of the whole substrates dihydroxyacetone phosphate and d-glyceraldehyde
3-phosphate [(kcat/Km)GAP and (kcat/Km)DHAP] and of the substrate pieces
glycolaldehyde and phosphite dianion (kcat/KHPiKGA)
are reported. The linear logarithmic correlation between these kinetic
parameters, with slope of 1.04 ± 0.03, shows that most mutations
of TIM result in an identical change in the activation barriers for
the catalyzed reactions of whole substrate and substrate pieces, so
that the transition states for these reactions are stabilized by similar
interactions with the protein catalyst. The second linear logarithmic
correlation [slope = 0.53 ± 0.16] between kcat for isomerization of GAP and Kd⧧ for phosphite dianion binding to the transition
state for wildtype and many mutant TIM-catalyzed reactions of substrate
pieces shows that ca. 50% of the wildtype TIM dianion binding energy,
eliminated by these mutations, is expressed at the wildtype Michaelis
complex, and ca. 50% is only expressed at the wildtype transition
state. Negative deviations from this correlation are observed when
the mutation results in a decrease in enzyme reactivity at the catalytic
site. The main effect of Y208T, Y208S, and Y208A mutations is to cause
a reduction in the total intrinsic dianion binding energy, but the
effect of Y208F extends to the catalytic site.
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Affiliation(s)
- Xiang Zhai
- Department of Chemistry, University at Buffalo, SUNY , Buffalo, New York 14260-3000, United States
| | - Tina L Amyes
- Department of Chemistry, University at Buffalo, SUNY , Buffalo, New York 14260-3000, United States
| | - John P Richard
- Department of Chemistry, University at Buffalo, SUNY , Buffalo, New York 14260-3000, United States
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16
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Minini L, Álvarez G, González M, Cerecetto H, Merlino A. Molecular docking and molecular dynamics simulation studies of Trypanosoma cruzi triosephosphate isomerase inhibitors. Insights into the inhibition mechanism and selectivity. J Mol Graph Model 2015; 58:40-9. [DOI: 10.1016/j.jmgm.2015.02.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 11/22/2014] [Accepted: 02/12/2015] [Indexed: 02/05/2023]
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17
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Yeon YJ, Park HJ, Park HY, Yoo YJ. Effect of His-tag location on the catalytic activity of 3-hydroxybutyrate dehydrogenase. BIOTECHNOL BIOPROC E 2014. [DOI: 10.1007/s12257-014-0089-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Zhai X, Malabanan MM, Amyes TL, Richard JP. Mechanistic Imperatives for Deprotonation of Carbon Catalyzed by Triosephosphate Isomerase: Enzyme-Activation by Phosphite Dianion. J PHYS ORG CHEM 2014; 27:269-276. [PMID: 24729658 PMCID: PMC3979633 DOI: 10.1002/poc.3195] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The mechanistic imperatives for catalysis of deprotonation of α-carbonyl carbon by triosephosphate isomerase (TIM) are discussed. There is a strong imperative to reduce the large thermodynamic barrier for deprotonation of carbon to form an enediolate reaction intermediate; and, a strong imperative for specificity in the expression of the intrinsic phosphodianion binding energy at the transition state for the enzyme-catalyzed reaction. Binding energies of 2 and 6 kcal/mol, respectively, have been determined for formation of phosphite dianion complexes to TIM and to the transition state for TIM-catalyzed deprotonation of the truncated substrate glycolaldehyde [T. L. Amyes, J. P. Richard, Biochemistry2007, 46, 5841]. We propose that the phosphite dianion binding energy, which is specifically expressed at the transition state complex, is utilized to stabilize a rare catalytically active loop-closed form of TIM. The results of experiments to probe the role of the side chains of Ile172 and Leu232 in activating the loop-closed form of TIM for catalysis of substrate deprotonation are discussed. Evidence is presented that the hydrophobic side chain of Ile172 assists in activating TIM for catalysis of substrate deprotonation through an enhancement of the basicity of the carboxylate side-chain of Glu167. Our experiments link the two imperatives for TIM-catalyzed deprotonation of carbon by providing evidence that the phosphodianion binding energy is utilized to drive an enzyme conformational change, which results in a reduction in the thermodynamic barrier to deprotonation of the carbon acid substrate at TIM compared with the barrier for deprotonation in water. The effects of a P168A mutation on the kinetic parameters for the reactions of whole and truncated substrates are discussed.
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Affiliation(s)
- Xiang Zhai
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY 14260, USA
| | - M Merced Malabanan
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY 14260, USA
| | - Tina L Amyes
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY 14260, USA
| | - John P Richard
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY 14260, USA
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19
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Zhai X, Amyes TL, Richard JP. Enzyme architecture: remarkably similar transition states for triosephosphate isomerase-catalyzed reactions of the whole substrate and the substrate in pieces. J Am Chem Soc 2014; 136:4145-8. [PMID: 24588650 PMCID: PMC3985921 DOI: 10.1021/ja501103b] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Values of (kcat/Km)GAP for triosephosphate
isomerase-catalyzed reactions
of (R)-glyceraldehyde 3-phosphate and kcat/KHPiKGA for reactions of the substrate pieces glycolaldehyde
and HPO32– have been determined for wild-type
and the following TIM mutants: I172V, I172A, L232A, and P168A (TIM
from Trypanosoma brucei brucei); a
208-TGAG for 208-YGGS loop 7 replacement mutant (L7RM, TIM from chicken
muscle); and, Y208T, Y208S, Y208A, Y208F and S211A (yeast TIM). A
superb linear logarithmic correlation, with slope of 1.04 ± 0.03,
is observed between the kinetic parameters for wild-type and most
mutant enzymes, with positive deviations for L232A and L7RM. The unit
slope shows that most mutations result in an identical change in the
activation barriers for the catalyzed reactions of whole substrate
and substrate pieces, so that the two transition states are stabilized
by similar interactions with the protein catalyst. This is consistent
with a role for dianions as active spectators, which hold TIM in a
catalytically active caged form.
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Affiliation(s)
- Xiang Zhai
- Department of Chemistry, University at Buffalo, State University of New York , Buffalo, New York 14260, United States
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20
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Katebi AR, Jernigan RL. The critical role of the loops of triosephosphate isomerase for its oligomerization, dynamics, and functionality. Protein Sci 2013; 23:213-28. [PMID: 24318986 DOI: 10.1002/pro.2407] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 12/01/2013] [Accepted: 12/03/2013] [Indexed: 11/11/2022]
Abstract
Triosephosphate isomerase (TIM) catalyzes the reaction to convert dihydroxyacetone phosphate into glyceraldehyde 3-phosphate, and vice versa. In most organisms, its functional oligomeric state is a homodimer; however, tetramer formation in hyperthermophiles is required for functional activity. The tetrameric TIM structure also provides added stability to the structure, enabling it to function at more extreme temperatures. We apply Principal Component Analysis to find that the TIM structure space is clearly divided into two groups--the open and the closed TIM structures. The distribution of the structures in the open set is much sparser than that in the closed set, showing a greater conformational diversity of the open structures. We also apply the Elastic Network Model to four different TIM structures--an engineered monomeric structure, a dimeric structure from a mesophile--Trypanosoma brucei, and two tetrameric structures from hyperthermophiles Thermotoga maritima and Pyrococcus woesei. We find that dimerization not only stabilizes the structures, it also enhances their functional dynamics. Moreover, tetramerization of the hyperthermophilic structures increases their functional loop dynamics, enabling them to function in the destabilizing environment of extreme temperatures. Computations also show that the functional loop motions, especially loops 6 and 7, are highly coordinated. In summary, our computations reveal the underlying mechanism of the allosteric regulation of the functional loops of the TIM structures, and show that tetramerization of the structure as found in the hyperthermophilic organisms is required to maintain the coordination of the functional loops at a level similar to that in the dimeric mesophilic structure.
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Affiliation(s)
- Ataur R Katebi
- Department of Biochemistry, Biophysics and Molecular Biology, LH Baker Center for Bioinformatics and Biological Statistics, Interdepartmental Program for Bioinformatics and Computational Biology, Iowa State University, Ames, Iowa, 50011-3020
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21
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Zhai X, Amyes TL, Wierenga RK, Loria JP, Richard JP. Structural mutations that probe the interactions between the catalytic and dianion activation sites of triosephosphate isomerase. Biochemistry 2013; 52:5928-40. [PMID: 23909928 DOI: 10.1021/bi401019h] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Triosephosphate isomerase (TIM) catalyzes the isomerization of dihydroxyacetone phosphate to form d-glyceraldehyde 3-phosphate. The effects of two structural mutations in TIM on the kinetic parameters for catalysis of the reaction of the truncated substrate glycolaldehyde (GA) and the activation of this reaction by phosphite dianion are reported. The P168A mutation results in similar 50- and 80-fold decreases in (kcat/Km)E and (kcat/Km)E·HPi, respectively, for deprotonation of GA catalyzed by free TIM and by the TIM·HPO(3)(2-) complex. The mutation has little effect on the observed and intrinsic phosphite dianion binding energy or the magnitude of phosphite dianion activation of TIM for catalysis of deprotonation of GA. A loop 7 replacement mutant (L7RM) of TIM from chicken muscle was prepared by substitution of the archaeal sequence 208-TGAG with 208-YGGS. L7RM exhibits a 25-fold decrease in (kcat/Km)E and a larger 170-fold decrease in (kcat/Km)E·HPi for reactions of GA. The mutation has little effect on the observed and intrinsic phosphodianion binding energy and only a modest effect on phosphite dianion activation of TIM. The observation that both the P168A and loop 7 replacement mutations affect mainly the kinetic parameters for TIM-catalyzed deprotonation but result in much smaller changes in the parameters for enzyme activation by phosphite dianion provides support for the conclusion that catalysis of proton transfer and dianion activation of TIM take place at separate, weakly interacting, sites in the protein catalyst.
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Affiliation(s)
- Xiang Zhai
- Department of Chemistry, University at Buffalo , Buffalo, New York 14260, United States
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22
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Affiliation(s)
- Artur Gora
- Loschmidt Laboratories,
Department
of Experimental Biology and Research Centre for Toxic Compounds in
the Environment, Faculty of Science, Masaryk University, Kamenice 5/A13, 625 00 Brno, Czech Republic
| | - Jan Brezovsky
- Loschmidt Laboratories,
Department
of Experimental Biology and Research Centre for Toxic Compounds in
the Environment, Faculty of Science, Masaryk University, Kamenice 5/A13, 625 00 Brno, Czech Republic
| | - Jiri Damborsky
- Loschmidt Laboratories,
Department
of Experimental Biology and Research Centre for Toxic Compounds in
the Environment, Faculty of Science, Masaryk University, Kamenice 5/A13, 625 00 Brno, Czech Republic
- International Centre for Clinical
Research, St. Anne’s University Hospital Brno, Pekarska 53, 656 91 Brno, Czech Republic
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23
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Ochoa-Leyva A, Montero-Morán G, Saab-Rincón G, Brieba LG, Soberón X. Alternative splice variants in TIM barrel proteins from human genome correlate with the structural and evolutionary modularity of this versatile protein fold. PLoS One 2013; 8:e70582. [PMID: 23950966 PMCID: PMC3741200 DOI: 10.1371/journal.pone.0070582] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 06/20/2013] [Indexed: 12/20/2022] Open
Abstract
After the surprisingly low number of genes identified in the human genome, alternative splicing emerged as a major mechanism to generate protein diversity in higher eukaryotes. However, it is still not known if its prevalence along the genome evolution has contributed to the overall functional protein diversity or if it simply reflects splicing noise. The (βα)8 barrel or TIM barrel is one of the most frequent, versatile, and ancient fold encountered among enzymes. Here, we analyze the structural modifications present in TIM barrel proteins from the human genome product of alternative splicing events. We found that 87% of all splicing events involved deletions; most of these events resulted in protein fragments that corresponded to the (βα)2, (βα)4, (βα)5, (βα)6, and (βα)7 subdomains of TIM barrels. Because approximately 7% of all the splicing events involved internal β-strand substitutions, we decided, based on the genomic data, to design β-strand and α-helix substitutions in a well-studied TIM barrel enzyme. The biochemical characterization of one of the chimeric variants suggests that some of the splice variants in the human genome with β-strand substitutions may be evolving novel functions via either the oligomeric state or substrate specificity. We provide results of how the splice variants represent subdomains that correlate with the independently folding and evolving structural units previously reported. This work is the first to observe a link between the structural features of the barrel and a recurrent genetic mechanism. Our results suggest that it is reasonable to expect that a sizeable fraction of splice variants found in the human genome represent structurally viable functional proteins. Our data provide additional support for the hypothesis of the origin of the TIM barrel fold through the assembly of smaller subdomains. We suggest a model of how nature explores new proteins through alternative splicing as a mechanism to diversify the proteins encoded in the human genome.
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Affiliation(s)
- Adrián Ochoa-Leyva
- Instituto Nacional de Medicina Genómica (INMEGEN), México City, México
- * E-mail: (AOL); (XS)
| | - Gabriela Montero-Morán
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México
| | - Gloria Saab-Rincón
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Luis G. Brieba
- Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México
| | - Xavier Soberón
- Instituto Nacional de Medicina Genómica (INMEGEN), México City, México
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
- * E-mail: (AOL); (XS)
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24
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Víctor SA, Yolanda MF, Araceli ZC, Lucía J, Abraham L. Characterization of a monoclonal antibody that specifically inhibits triosephosphate isomerase activity of Taenia solium. Exp Parasitol 2013; 134:495-503. [DOI: 10.1016/j.exppara.2013.05.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 04/20/2013] [Accepted: 05/09/2013] [Indexed: 01/17/2023]
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25
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Hernández-Alcántara G, Torres-Larios A, Enríquez-Flores S, García-Torres I, Castillo-Villanueva A, Méndez ST, de la Mora-de la Mora I, Gómez-Manzo S, Torres-Arroyo A, López-Velázquez G, Reyes-Vivas H, Oria-Hernández J. Structural and functional perturbation of Giardia lamblia triosephosphate isomerase by modification of a non-catalytic, non-conserved region. PLoS One 2013; 8:e69031. [PMID: 23894402 PMCID: PMC3718800 DOI: 10.1371/journal.pone.0069031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Accepted: 06/04/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND We have previously proposed triosephosphate isomerase of Giardia lamblia (GlTIM) as a target for rational drug design against giardiasis, one of the most common parasitic infections in humans. Since the enzyme exists in the parasite and the host, selective inhibition is a major challenge because essential regions that could be considered molecular targets are highly conserved. Previous biochemical evidence showed that chemical modification of the non-conserved non-catalytic cysteine 222 (C222) inactivates specifically GlTIM. The inactivation correlates with the physicochemical properties of the modifying agent: addition of a non-polar, small chemical group at C222 reduces the enzyme activity by one half, whereas negatively charged, large chemical groups cause full inactivation. RESULTS In this work we used mutagenesis to extend our understanding of the functional and structural effects triggered by modification of C222. To this end, six GlTIM C222 mutants with side chains having diverse physicochemical characteristics were characterized. We found that the polarity, charge and volume of the side chain in the mutant amino acid differentially alter the activity, the affinity, the stability and the structure of the enzyme. The data show that mutagenesis of C222 mimics the effects of chemical modification. The crystallographic structure of C222D GlTIM shows the disruptive effects of introducing a negative charge at position 222: the mutation perturbs loop 7, a region of the enzyme whose interactions with the catalytic loop 6 are essential for TIM stability, ligand binding and catalysis. The amino acid sequence of TIM in phylogenetic diverse groups indicates that C222 and its surrounding residues are poorly conserved, supporting the proposal that this region is a good target for specific drug design. CONCLUSIONS The results demonstrate that it is possible to inhibit species-specifically a ubiquitous, structurally highly conserved enzyme by modification of a non-conserved, non-catalytic residue through long-range perturbation of essential regions.
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Affiliation(s)
- Gloria Hernández-Alcántara
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Alfredo Torres-Larios
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Sergio Enríquez-Flores
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Itzhel García-Torres
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Adriana Castillo-Villanueva
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Sara T. Méndez
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | | | - Saúl Gómez-Manzo
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Angélica Torres-Arroyo
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Gabriel López-Velázquez
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Horacio Reyes-Vivas
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
- * E-mail: (JOH); (HRV)
| | - Jesús Oria-Hernández
- Laboratorio de Bioquímica-Genética, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
- * E-mail: (JOH); (HRV)
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26
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Gagné D, Doucet N. Structural and functional importance of local and global conformational fluctuations in the RNase A superfamily. FEBS J 2013; 280:5596-607. [PMID: 23763751 DOI: 10.1111/febs.12371] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/10/2013] [Accepted: 05/13/2013] [Indexed: 12/11/2022]
Abstract
Understanding the relationship between protein structure and flexibility is of utmost importance for deciphering the tremendous rates of reactions catalyzed by enzyme biocatalysts. It has been postulated that protein homologs have evolved similar dynamic fluctuations to promote catalytic function, a property that would presumably be encoded in their structural fold. Using one of the best-characterized enzyme systems of the past century, we explore this hypothesis by comparing the numerous and diverse flexibility reports available for a number of structural and functional homologs of the pancreatic-like RNase A superfamily. Using examples from the literature and from our own work, we cover recent and historical evidence pertaining to the highly dynamic nature of this important structural fold, as well as the presumed importance of local and global concerted motions on the ribonucleolytic function. This minireview does not pretend to cover the overwhelming RNase A literature in a comprehensive manner; rather, efforts have been made to focus on the characterization of multiple timescale motions observed in the free and/or ligand-bound structural homologs as they proceed along the reaction coordinates. Although each characterized enzyme of this architectural fold shows unique motional features on a local scale, accumulating evidence from X-ray crystallography, NMR spectroscopy and molecular dynamics simulations suggests that global dynamic fluctuations, such as the functionally relevant hinge-bending motion observed in the prototypical RNase A, are shared between homologs of the pancreatic-like RNase superfamily. These observations support the hypothesis that analogous dynamic residue clusters are evolutionarily conserved among structural and functional homologs catalyzing similar enzymatic reactions.
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Affiliation(s)
- Donald Gagné
- INRS-Institut Armand-Frappier, Université du Québec, Laval, Québec, Canada
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27
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Boehr DD, Schnell JR, McElheny D, Bae SH, Duggan BM, Benkovic SJ, Dyson HJ, Wright PE. A distal mutation perturbs dynamic amino acid networks in dihydrofolate reductase. Biochemistry 2013; 52:4605-19. [PMID: 23758161 DOI: 10.1021/bi400563c] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Correlated networks of amino acids have been proposed to play a fundamental role in allostery and enzyme catalysis. These networks of amino acids can be traced from surface-exposed residues all the way into the active site, and disruption of these networks can decrease enzyme activity. Substitution of the distal Gly121 residue in Escherichia coli dihydrofolate reductase results in an up to 200-fold decrease in the hydride transfer rate despite the fact that the residue is located 15 Å from the active-site center. In this study, nuclear magnetic resonance relaxation experiments are used to demonstrate that dynamics on the picosecond to nanosecond and microsecond to millisecond time scales are changed significantly in the G121V mutant of dihydrofolate reductase. In particular, picosecond to nanosecond time scale dynamics are decreased in the FG loop (containing the mutated residue at position 121) and the neighboring active-site loop (the Met20 loop) in the mutant compared to those of the wild-type enzyme, suggesting that these loops are dynamically coupled. Changes in methyl order parameters reveal a pathway by which dynamic perturbations can be propagated more than 25 Å across the protein from the site of mutation. All of the enzyme complexes, including the model Michaelis complex with folate and nicotinamide adenine dinucleotide phosphate bound, assume an occluded ground-state conformation, and we do not observe sampling of a higher-energy closed conformation by (15)N R2 relaxation dispersion experiments. This is highly significant, because it is only in the closed conformation that the cofactor and substrate reactive centers are positioned for reaction. The mutation also impairs microsecond to millisecond time scale fluctuations that have been implicated in the release of product from the wild-type enzyme. Our results are consistent with an important role for Gly121 in controlling protein dynamics critical for enzyme function and further validate the dynamic energy landscape hypothesis of enzyme catalysis.
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Affiliation(s)
- David D Boehr
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Jason R Schnell
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Dan McElheny
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Sung-Hun Bae
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Brendan M Duggan
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Stephen J Benkovic
- The Pennsylvania State University, Department of Chemistry, 414 Wartik Laboratory, University Park, PA 16802, USA
| | - H Jane Dyson
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Peter E Wright
- Department of Integrative Structural and Computational Biology and the Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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28
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Mukherjee S, Roychowdhury A, Dutta D, Das AK. Crystal structures of triosephosphate isomerase from methicillin resistant Staphylococcus aureus MRSA252 provide structural insights into novel modes of ligand binding and unique conformations of catalytic loop. Biochimie 2012; 94:2532-44. [PMID: 22813930 DOI: 10.1016/j.biochi.2012.07.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 07/04/2012] [Indexed: 10/28/2022]
Abstract
Staphylococcus aureus is one of the most dreaded pathogens worldwide and emergence of notorious antibiotic resistant strains have further exacerbated the present scenario. The glycolytic enzyme, triosephosphate isomerase (TIM) is one of the cell envelope proteins of the coccus and is involved in biofilm formation. It also plays an instrumental role in adherence and invasion of the bacteria into the host cell. To structurally characterize this important enzyme and analyze it's interaction with different inhibitors, substrate and transition state analogues, the present article describes several crystal structures of SaTIM alone and in complex with different ligands: glycerol-3-phosphate (G3P), glycerol-2-phosphate (G2P), 3-phosphoglyceric acid (3PG) and 2-phosphoglyceric acid (2PG). Unique conformations of the catalytic loop 6 (L6) has been observed in the different complexes. It is found to be in "almost closed" conformation in both subunits of the structure complexed to G3P. However L6 adopts the open conformation in presence of G2P and 2PG. The preference of the conformation of the catalytic loop can be correlated with the position of the phosphate group in the ligand. Novel modes of binding have been observed for G2P and 3PG for the very first time. The triose moiety is oriented away from the catalytic residues and occupies an entirely different position in some subunits. A completely new binding site for phosphate has also been identified in the complex with 2PG which differs substantially from the conventional phosphate binding site of the ligand in the crystal structures of TIM determined so far.
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Affiliation(s)
- Somnath Mukherjee
- Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302, West Bengal, India
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29
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Danielson ML, Lill MA. Predicting flexible loop regions that interact with ligands: the challenge of accurate scoring. Proteins 2011; 80:246-60. [PMID: 22072600 DOI: 10.1002/prot.23199] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 09/06/2011] [Accepted: 09/13/2011] [Indexed: 01/12/2023]
Abstract
Flexible loop regions play a critical role in the biological function of many proteins and have been shown to be involved in ligand binding. In the context of structure-based drug design, using or predicting an incorrect loop configuration can be detrimental to the study if the loop is capable of interacting with the ligand. Three protein systems, each with at least one flexible loop region in close proximity to the known binding site, were selected for loop prediction using the CorLps program; a six residue loop region from phosphoribosylglycinamide formyltransferase (GART), two nine residue loop regions from cytochrome P450 (CYP) 119, and an 11 residue loop region from enolase were selected for loop prediction. The results of this study indicate that the statistically based DFIRE scoring function implemented in the CorLps program did not accurately rank native-like predicted loop configurations in any protein system. In an attempt to improve the ranking of the native-like predicted loop configurations, the MM/GBSA and the optimized MM/GBSA-dsr scoring functions were used to re-rank the predicted loops with and without bound ligand. In general, single snapshot MM/GBSA scoring provided the best ranking of native-like loop configurations. Based on the scoring function analyses presented, the optimal ranking of native-like loop configurations is still a difficult challenge and the choice of the "best" scoring function appears to be system dependent.
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Affiliation(s)
- Matthew L Danielson
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
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30
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Strambini GB, Gonnelli M. Influence of Denaturants on Native-State Structural Fluctuations in Azurin Probed by Molecular Size-Dependent Quenching of Trp Phosphorescence. J Phys Chem B 2011; 115:13755-64. [DOI: 10.1021/jp208397m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Margherita Gonnelli
- Consiglio Nazionale delle Ricerche, Istituto di Biofisica, 56124 Pisa, Italy
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Triosephosphate Isomerase by Consensus Design: Dramatic Differences in Physical Properties and Activity of Related Variants. J Mol Biol 2011; 413:195-208. [DOI: 10.1016/j.jmb.2011.08.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Revised: 07/23/2011] [Accepted: 08/01/2011] [Indexed: 11/23/2022]
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Venkatesan R, Alahuhta M, Pihko PM, Wierenga RK. High resolution crystal structures of triosephosphate isomerase complexed with its suicide inhibitors: the conformational flexibility of the catalytic glutamate in its closed, liganded active site. Protein Sci 2011; 20:1387-97. [PMID: 21633986 PMCID: PMC3189524 DOI: 10.1002/pro.667] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2011] [Accepted: 05/19/2011] [Indexed: 01/07/2023]
Abstract
The key residue of the active site of triosephosphate isomerase (TIM) is the catalytic glutamate, which is proposed to be important (i) as a catalytic base, for initiating the reaction, as well as (ii) for the subsequent proton shuttling steps. The structural properties of this glutamate in the liganded complex have been investigated by studying the high resolution crystal structures of typanosomal TIM, complexed with three suicide inhibitors: (S)-glycidol phosphate ((S)-GOP, at 0.99 Å resolution), (R)-glycidol phosphate, ((R)-GOP, at 1.08 Å resolution), and bromohydroxyacetone phosphate (BHAP, at 1.97 Å resolution). The structures show that in the (S)-GOP active site this catalytic glutamate is in the well characterized, competent conformation. However, an unusual side chain conformation is observed in the (R)-GOP and BHAP complexes. In addition, Glu97, salt bridged to the catalytic lysine in the competent active site, adopts an unusual side chain conformation in these two latter complexes. The higher chemical reactivity of (S)-GOP compared with (R)-GOP, as known from solution studies, can be understood: the structures indicate that in the case of (S)-GOP, Glu167 can attack the terminal carbon of the epoxide in a stereoelectronically favored, nearly linear OCO arrangement, but this is not possible for the (R)-GOP isomer. These structures confirm the previously proposed conformational flexibility of the catalytic glutamate in its closed, liganded state. The importance of this conformational flexibility for the proton shuttling steps in the TIM catalytic cycle, which is apparently achieved by a sliding motion of the side chain carboxylate group above the enediolate plane, is also discussed.
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Affiliation(s)
- Rajaram Venkatesan
- Biocenter Oulu and Department of Biochemistry, FIN 90014, University of OuluFinland
| | - Markus Alahuhta
- Biocenter Oulu and Department of Biochemistry, FIN 90014, University of OuluFinland
| | - Petri M Pihko
- Department of Chemistry and Nanoscience Center, University of Jyväskylä, FIN 40014, University of JyväskyläFinland
| | - Rik K Wierenga
- Biocenter Oulu and Department of Biochemistry, FIN 90014, University of OuluFinland,*Correspondence to: Rik K. Wierenga, Biocenter Oulu and Department of Biochemistry, P.O. Box 3000, FIN 90014, University of Oulu, Finland. E-mail:
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Sidhu A, Surolia A, Robertson AD, Sundd M. A hydrogen bond regulates slow motions in ubiquitin by modulating a β-turn flip. J Mol Biol 2011; 411:1037-48. [PMID: 21741979 DOI: 10.1016/j.jmb.2011.06.044] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2011] [Revised: 06/16/2011] [Accepted: 06/27/2011] [Indexed: 10/18/2022]
Abstract
Proteins exist as conformational ensembles composed of multiple interchanging substates separated by kinetic barriers. Interconverting conformations are often difficult to probe, owing to their sparse population and transient nature. Here, we report the identification and characterization of a subset of conformations in ubiquitin that participate in microsecond-to-millisecond motions in the amides of Ile23, Asn25, and Thr55. A novel side chain to the backbone hydrogen bond that regulates these motions has also been identified. Combining our NMR studies with the available X-ray data, we have unearthed the physical process underlying slow motions-the interconversion of a type I into a type II β-turn flip at residues Glu51 through Arg54. Interestingly, the dominant conformer of wild-type ubiquitin observed in solution near neutral pH is only represented by about 22% of the crystal structures. The conformers generated as a result of the dynamics of the hydrogen bond appear to be correlated to ligand recognition by ubiquitin.
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Affiliation(s)
- Arshdeep Sidhu
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110 067, India
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34
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Samanta M, Murthy MRN, Balaram H, Balaram P. Revisiting the Mechanism of the Triosephosphate Isomerase Reaction: The Role of the Fully Conserved Glutamic Acid 97 Residue. Chembiochem 2011; 12:1886-96. [DOI: 10.1002/cbic.201100116] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Indexed: 11/09/2022]
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Ochoa-Leyva A, Barona-Gómez F, Saab-Rincón G, Verdel-Aranda K, Sánchez F, Soberón X. Exploring the Structure-Function Loop Adaptability of a (β/α)(8)-Barrel Enzyme through Loop Swapping and Hinge Variability. J Mol Biol 2011; 411:143-57. [PMID: 21635898 DOI: 10.1016/j.jmb.2011.05.027] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 03/31/2011] [Accepted: 05/18/2011] [Indexed: 11/26/2022]
Abstract
Evolution of proteins involves sequence changes that are frequently localized at loop regions, revealing their important role in natural evolution. However, the development of strategies to understand and imitate such events constitutes a challenge to design novel enzymes in the laboratory. In this study, we show how to adapt loop swapping as semiautonomous units of functional groups in an enzyme with the (β/α)(8)-barrel and how this functional adaptation can be measured in vivo. To mimic the natural mechanism providing loop variability in antibodies, we developed an overlap PCR strategy. This includes introduction of sequence diversity at two hinge residues, which connect the new loops with the rest of the protein scaffold, and we demonstrate that this is necessary for a successful exploration of functional sequence space. This design allowed us to explore the sequence requirements to functional adaptation of each loop replacement that may not be sampled otherwise. Libraries generated following this strategy were evaluated in terms of their folding competence and their functional proficiency, an observation that was formalized as a Structure-Function Loop Adaptability value. Molecular details about the function and structure of some variants were obtained by enzyme kinetics and circular dichroism. This strategy yields functional variants that retain the original activity at higher frequencies, suggesting a new strategy for protein engineering that incorporates a more divergent sequence exploration beyond that limited to point mutations. We discuss how this approach may provide insights into the mechanism of enzyme evolution and function.
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Affiliation(s)
- Adrián Ochoa-Leyva
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Avenida Universidad 2001, Cuernavaca, C.P. 62210, México
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36
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Davulcu O, Skalicky JJ, Chapman MS. Rate-limiting domain and loop motions in arginine kinase. Biochemistry 2011; 50:4011-8. [PMID: 21425868 DOI: 10.1021/bi101664u] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Arginine kinase catalyzes the reversible transfer of a phosphoryl group between ATP and arginine. It is the arthropod homologue of creatine kinase, buffering cellular ATP levels. Crystal structures of arginine kinase, in substrate-free and substrate-bound forms, have revealed large conformational changes associated with the catalytic cycle. Recent nuclear magnetic resonance identified movements of the N-terminal domain and a loop comprising residues I182--G209 with conformational exchange rates in the substrate-free enzyme similar to the turnover rate. Here, to understand whether these motions might be rate-limiting, we determined activation barriers for both the intrinsic dynamics and enzyme turnover using measurements over a temperature range of 15-30 °C. (15)N transverse relaxation dispersion yields activation barriers of 46 ± 8 and 34 ± 12 kJ/mol for the N-terminal domain and I182--G209 loop, respectively. An activation barrier of 34 ± 13 kJ/mol was obtained for enzyme turnover from steady-state kinetics. The similarity between the activation barriers is indeed consistent with turnover being limited by backbone conformational dynamics and pinpoints the locations of potentially rate-limiting motions.
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Affiliation(s)
- Omar Davulcu
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239-3098, United States
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37
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Wierenga RK, Kapetaniou EG, Venkatesan R. Triosephosphate isomerase: a highly evolved biocatalyst. Cell Mol Life Sci 2010; 67:3961-82. [PMID: 20694739 PMCID: PMC11115733 DOI: 10.1007/s00018-010-0473-9] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 07/15/2010] [Accepted: 07/16/2010] [Indexed: 02/04/2023]
Abstract
Triosephosphate isomerase (TIM) is a perfectly evolved enzyme which very fast interconverts dihydroxyacetone phosphate and D: -glyceraldehyde-3-phosphate. Its catalytic site is at the dimer interface, but the four catalytic residues, Asn11, Lys13, His95 and Glu167, are from the same subunit. Glu167 is the catalytic base. An important feature of the TIM active site is the concerted closure of loop-6 and loop-7 on ligand binding, shielding the catalytic site from bulk solvent. The buried active site stabilises the enediolate intermediate. The catalytic residue Glu167 is at the beginning of loop-6. On closure of loop-6, the Glu167 carboxylate moiety moves approximately 2 Å to the substrate. The dynamic properties of the Glu167 side chain in the enzyme substrate complex are a key feature of the proton shuttling mechanism. Two proton shuttling mechanisms, the classical and the criss-cross mechanism, are responsible for the interconversion of the substrates of this enolising enzyme.
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Affiliation(s)
- R K Wierenga
- Biocenter Oulu and Department of Biochemistry, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland.
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38
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Stratton MM, Cutler TA, Ha JH, Loh SN. Probing local structural fluctuations in myoglobin by size-dependent thiol-disulfide exchange. Protein Sci 2010; 19:1587-94. [PMID: 20572017 DOI: 10.1002/pro.440] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
All proteins undergo local structural fluctuations (LSFs) or breathing motions. These motions are likely to be important for function but are poorly understood. LSFs were initially defined by amide hydrogen exchange (HX) experiments as opening events, which expose a small number of backbone amides to (1)H/(2)H exchange, but whose exchange rates are independent of denaturant concentration. Here, we use size-dependent thiol-disulfide exchange (SX) to characterize LSFs in single cysteine-containing variants of myoglobin (Mb). SX complements HX by providing information on motions that disrupt side chain packing interactions. Most importantly, probe reagents of different sizes and chemical properties can be used to characterize the size of structural opening events and the properties of the open state. We use thiosulfonate reagents (126-274 Da) to survey access to Cys residues, which are buried at specific helical packing interfaces in Mb. In each case, the free energy of opening increases linearly with the radius of gyration of the probe reagent. The slope and the intercept are interpreted to yield information on the size of the opening events that expose the buried thiol groups. The slope parameter varies by over 10-fold among Cys positions tested, suggesting that the sizes of breathing motions vary substantially throughout the protein. Our results provide insight to the longstanding question: how rigid or flexible are proteins in their native states?
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Affiliation(s)
- Margaret M Stratton
- Department of Biochemistry and Molecular Biology, State University of New York Upstate Medical University, Syracuse, New York 13210, USA
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39
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Kleckner IR, Foster MP. An introduction to NMR-based approaches for measuring protein dynamics. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2010; 1814:942-68. [PMID: 21059410 DOI: 10.1016/j.bbapap.2010.10.012] [Citation(s) in RCA: 339] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Revised: 10/27/2010] [Accepted: 10/29/2010] [Indexed: 01/15/2023]
Abstract
Proteins are inherently flexible at ambient temperature. At equilibrium, they are characterized by a set of conformations that undergo continuous exchange within a hierarchy of spatial and temporal scales ranging from nanometers to micrometers and femtoseconds to hours. Dynamic properties of proteins are essential for describing the structural bases of their biological functions including catalysis, binding, regulation and cellular structure. Nuclear magnetic resonance (NMR) spectroscopy represents a powerful technique for measuring these essential features of proteins. Here we provide an introduction to NMR-based approaches for studying protein dynamics, highlighting eight distinct methods with recent examples, contextualized within a common experimental and analytical framework. The selected methods are (1) Real-time NMR, (2) Exchange spectroscopy, (3) Lineshape analysis, (4) CPMG relaxation dispersion, (5) Rotating frame relaxation dispersion, (6) Nuclear spin relaxation, (7) Residual dipolar coupling, (8) Paramagnetic relaxation enhancement. This article is part of a Special Issue entitled: Protein Dynamics: Experimental and Computational Approaches.
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Affiliation(s)
- Ian R Kleckner
- The Ohio State University Biophysics Program, 484 West 12th Ave Room 776, Columbus, OH 43210, USA
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40
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Malabanan MM, Amyes TL, Richard JP. A role for flexible loops in enzyme catalysis. Curr Opin Struct Biol 2010; 20:702-10. [PMID: 20951028 DOI: 10.1016/j.sbi.2010.09.005] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2010] [Revised: 09/09/2010] [Accepted: 09/10/2010] [Indexed: 11/29/2022]
Abstract
Triosephosphate isomerase (TIM), glycerol 3-phosphate dehydrogenase, and orotidine 5'-monophosphate decarboxylase each use the binding energy from the interaction of phosphite dianion with a flexible phosphate gripper loop to activate a second, phosphodianion-truncated, substrate towards enzyme-catalyzed proton transfer, hydride transfer, and decarboxylation, respectively. Studies on TIM suggest that the most important general effect of loop closure over the substrate phosphodianion, and the associated conformational changes, is to extrude water from the enzyme active site. This should cause a decrease in the effective active-site dielectric constant, and an increase in transition state stabilization from enhanced electrostatic interactions with polar amino acid side chains. The most important specific effect of these conformational changes is to increase the basicity of the carboxylate side chain of the active site glutamate base by its placement in a 'hydrophobic cage'.
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Affiliation(s)
- M Merced Malabanan
- Department of Chemistry, University at Buffalo, SUNY, Buffalo, NY 14260-3000, USA
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41
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Danielson ML, Lill MA. New computational method for prediction of interacting protein loop regions. Proteins 2010; 78:1748-59. [PMID: 20186974 DOI: 10.1002/prot.22690] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Flexible loop regions of proteins play a crucial role in many biological functions such as protein-ligand recognition, enzymatic catalysis, and protein-protein association. To date, most computational methods that predict the conformational states of loops only focus on individual loop regions. However, loop regions are often spatially in close proximity to one another and their mutual interactions stabilize their conformations. We have developed a new method, titled CorLps, capable of simultaneously predicting such interacting loop regions. First, an ensemble of individual loop conformations is generated for each loop region. The members of the individual ensembles are combined and are accepted or rejected based on a steric clash filter. After a subsequent side-chain optimization step, the resulting conformations of the interacting loops are ranked by the statistical scoring function DFIRE that originated from protein structure prediction. Our results show that predicting interacting loops with CorLps is superior to sequential prediction of the two interacting loop regions, and our method is comparable in accuracy to single loop predictions. Furthermore, improved predictive accuracy of the top-ranked solution is achieved for 12-residue length loop regions by diversifying the initial pool of individual loop conformations using a quality threshold clustering algorithm.
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Affiliation(s)
- Matthew L Danielson
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana 47907, USA
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42
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Noda-García L, Camacho-Zarco AR, Verdel-Aranda K, Wright H, Soberón X, Fülöp V, Barona-Gómez F. Identification and analysis of residues contained on beta --> alpha loops of the dual-substrate (beta alpha)8 phosphoribosyl isomerase A specific for its phosphoribosyl anthranilate isomerase activity. Protein Sci 2010; 19:535-43. [PMID: 20066665 DOI: 10.1002/pro.331] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A good model to experimentally explore evolutionary hypothesis related to enzyme function is the ancient-like dual-substrate (beta alpha)(8) phosphoribosyl isomerase A (PriA), which takes part in both histidine and tryptophan biosynthesis in Streptomyces coelicolor and related organisms. In this study, we determined the Michaelis-Menten enzyme kinetics for both isomerase activities in wild-type PriA from S. coelicolor and in selected single-residue monofunctional mutants, identified after Escherichia coli in vivo complementation experiments. Structural and functional analyses of a hitherto unnoticed residue contained on the functionally important beta --> alpha loop 5, namely, Arg(139), which was postulated on structural grounds to be important for the dual-substrate specificity of PriA, is presented for the first time. Indeed, enzyme kinetics analyses done on the mutant variants PriA_Ser(81)Thr and PriA_Arg(139)Asn showed that these residues, which are contained on beta --> alpha loops and in close proximity to the N-terminal phosphate-binding site, are essential solely for the phosphoribosyl anthranilate isomerase activity of PriA. Moreover, analysis of the X-ray crystallographic structure of PriA_Arg(139)Asn elucidated at 1.95 A herein strongly implicates the occurrence of conformational changes in this beta --> alpha loop as a major structural feature related to the evolution of the dual-substrate specificity of PriA. It is suggested that PriA has evolved by tuning a fine energetic balance that allows the sufficient degree of structural flexibility needed for accommodating two topologically dissimilar substrates--within a bifunctional and thus highly constrained active site--without compromising its structural stability.
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Affiliation(s)
- Lianet Noda-García
- Evolution of Metabolic Diversity Laboratory, Laboratorio Nacional de Genómica para la Biodiversidad (Langebio), CINVESTAV-IPN, Km 9.6 Libramiento Norte, Carretera Irapuato-León, Irapuato, C.P. 36822, México
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43
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Fitzkee NC, Masse JE, Shen Y, Davies DR, Bax A. Solution conformation and dynamics of the HIV-1 integrase core domain. J Biol Chem 2010; 285:18072-84. [PMID: 20363759 DOI: 10.1074/jbc.m110.113407] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) integrase (IN) is a critical enzyme involved in infection. It catalyzes two reactions to integrate the viral cDNA into the host genome, 3' processing and strand transfer, but the dynamic behavior of the active site during catalysis of these two processes remains poorly characterized. NMR spectroscopy can reveal important structural details about enzyme mechanisms, but to date the IN catalytic core domain has proven resistant to such an analysis. Here, we present the first NMR studies of a soluble variant of the catalytic core domain. The NMR chemical shifts are found to corroborate structures observed in crystals, and confirm prior studies suggesting that the alpha4 helix extends toward the active site. We also observe a dramatic improvement in NMR spectra with increasing MgCl(2) concentration. This improvement suggests a structural transition not only near the active site residues but also throughout the entire molecule as IN binds Mg(2+). In particular, the stability of the core domain is linked to the conformation of its C-terminal helix, which has implications for relative domain orientation in the full-length enzyme. (15)N relaxation experiments further show that, although conformationally flexible, the catalytic loop of IN is not fully disordered in the absence of DNA. Indeed, automated chemical shift-based modeling of the active site loop reveals several stable clusters that show striking similarity to a recent crystal structure of prototype foamy virus IN bound to DNA.
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Affiliation(s)
- Nicholas C Fitzkee
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, Maryland 20892, USA
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