1
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Servant G, Kenakin T. A Pharmacological perspective on the temporal properties of sweeteners. Pharmacol Res 2024; 204:107211. [PMID: 38744400 DOI: 10.1016/j.phrs.2024.107211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 05/06/2024] [Accepted: 05/09/2024] [Indexed: 05/16/2024]
Abstract
Several non-caloric sweeteners exhibit a delay in sweetness onset and a sweetness linger after sampling. These temporal properties are thought to be the result of non-specific interactions with cell membranes and proteins in the oral cavity. Data and analysis presented in this report also support the potential involvement of receptor affinity and binding kinetics to this phenomenon. In general, affected sweeteners exhibit distinctly higher binding affinity compared to carbohydrate sweeteners, which do not have temporal issues. In addition, binding kinetic simulations illustrate much slower receptor binding association and dissociation kinetics for a set of non-caloric sweeteners presenting temporal issues, in comparison to carbohydrate sweeteners. So, the higher affinity of some non-caloric sweeteners, dictating lower use levels, and affecting binding kinetics, could contribute to their delay and linger in sweetness perception. Simple pharmacology principles could explain, at least in part, some of the temporal issues of sweeteners.
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Affiliation(s)
- Guy Servant
- dsm-firmenich, 10636 Scripps Summit Court #201, San Diego, CA 92131, USA.
| | - Terry Kenakin
- Department of Pharmacology, University of North Carolina School of Medicine, 120 Mason Farm Rd., 4042 Genetic Medicine CB #7365, Chapel Hill, NC 27599, USA
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2
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Mukhametgalieva A, Mir SA, Shaihutdinova Z, Masson P. Human Plasma Butyrylcholinesterase Hydrolyzes Atropine: Kinetic and Molecular Modeling Studies. Molecules 2024; 29:2140. [PMID: 38731631 PMCID: PMC11085540 DOI: 10.3390/molecules29092140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 04/29/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024] Open
Abstract
The participation of butyrylcholinesterase (BChE) in the degradation of atropine has been recurrently addressed for more than 70 years. However, no conclusive answer has been provided for the human enzyme so far. In the present work, a steady-state kinetic analysis performed by spectrophotometry showed that highly purified human plasma BChE tetramer slowly hydrolyzes atropine at pH 7.0 and 25 °C. The affinity of atropine for the enzyme is weak, and the observed kinetic rates versus the atropine concentration was of the first order: the maximum atropine concentration in essays was much less than Km. Thus, the bimolecular rate constant was found to be kcat/Km = 7.7 × 104 M-1 min-1. Rough estimates of catalytic parameters provided slow kcat < 40 min-1 and high Km = 0.3-3.3 mM. Then, using a specific organophosphoryl agent, echothiophate, the time-dependent irreversible inhibition profiles of BChE for hydrolysis of atropine and the standard substrate butyrylthiocholine (BTC) were investigated. This established that both substrates are hydrolyzed at the same site, i.e., S198, as for all substrates of this enzyme. Lastly, molecular docking provided evidence that both atropine isomers bind to the active center of BChE. However, free energy perturbations yielded by the Bennett Acceptance Ratio method suggest that the L-atropine isomer is the most reactive enantiomer. In conclusion, the results provided evidence that plasma BChE slowly hydrolyzes atropine but should have no significant role in its metabolism under current conditions of medical use and even under administration of the highest possible doses of this antimuscarinic drug.
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Affiliation(s)
- Aliya Mukhametgalieva
- Laboratory of Biochemical Neuropharmacology, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia; (A.M.); (Z.S.)
| | - Showkat Ahmad Mir
- School of Life Sciences, Sambalpur University, Jyotivihar, Burla 768019, India;
| | - Zukhra Shaihutdinova
- Laboratory of Biochemical Neuropharmacology, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia; (A.M.); (Z.S.)
| | - Patrick Masson
- Laboratory of Biochemical Neuropharmacology, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia; (A.M.); (Z.S.)
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3
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Stenström O, Diehl C, Modig K, Akke M. Ligand-induced protein transition state stabilization switches the binding pathway from conformational selection to induced fit. Proc Natl Acad Sci U S A 2024; 121:e2317747121. [PMID: 38527204 PMCID: PMC10998626 DOI: 10.1073/pnas.2317747121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 02/29/2024] [Indexed: 03/27/2024] Open
Abstract
Protein-ligand complex formation is fundamental to biological function. A central question is whether proteins spontaneously adopt binding-competent conformations to which ligands bind conformational selection (CS) or whether ligands induce the binding-competent conformation induced fit (IF). Here, we resolve the CS and IF binding pathways by characterizing protein conformational dynamics over a wide range of ligand concentrations using NMR relaxation dispersion. We determined the relative flux through the two pathways using a four-state binding model that includes both CS and IF. Experiments conducted without ligand show that galectin-3 exchanges between the ground-state conformation and a high-energy conformation similar to the ligand-bound conformation, demonstrating that CS is a plausible pathway. Near-identical crystal structures of the apo and ligand-bound states suggest that the high-energy conformation in solution corresponds to the apo crystal structure. Stepwise additions of the ligand lactose induce progressive changes in the relaxation dispersions that we fit collectively to the four-state model, yielding all microscopic rate constants and binding affinities. The ligand affinity is higher for the bound-like conformation than for the ground state, as expected for CS. Nonetheless, the IF pathway contributes greater than 70% of the total flux even at low ligand concentrations. The higher flux through the IF pathway is explained by considerably higher rates of exchange between the two protein conformations in the ligand-associated state. Thus, the ligand acts to decrease the activation barrier between protein conformations in a manner reciprocal to enzymatic transition-state stabilization of reactions involving ligand transformation.
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Affiliation(s)
- Olof Stenström
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, SE-221 00Lund, Sweden
| | - Carl Diehl
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, SE-221 00Lund, Sweden
| | - Kristofer Modig
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, SE-221 00Lund, Sweden
| | - Mikael Akke
- Division of Biophysical Chemistry, Center for Molecular Protein Science, Department of Chemistry, Lund University, SE-221 00Lund, Sweden
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4
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Di Cera E. A simple method to resolve rate constants when the binding mechanism obeys induced fit or conformational selection. J Biol Chem 2024; 300:107131. [PMID: 38432634 PMCID: PMC10979105 DOI: 10.1016/j.jbc.2024.107131] [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: 01/02/2024] [Revised: 02/10/2024] [Accepted: 02/24/2024] [Indexed: 03/05/2024] Open
Abstract
Many interactions involving a ligand and its molecular target are studied by rapid kinetics using a stopped-flow apparatus. Information obtained from these studies is often limited to a single, saturable relaxation that is insufficient to resolve all independent rate constants even for a two-step mechanism of binding obeying induced fit (IF) or conformational selection (CS). We introduce a simple method of general applicability where this limitation is overcome. The method accurately reproduces the rate constants for ligand binding to the serine protease thrombin determined independently from the analysis of multiple relaxations. Application to the inactive zymogen precursor of thrombin, prethrombin-2, resolves all rate constants for a binding mechanism of IF or CS from a single, saturable relaxation. Comparison with thrombin shows that the prethrombin-2 to thrombin conversion enhances ligand binding to the active site not by improving accessibility through the value of kon but by reducing the rate of dissociation koff. The conclusion holds regardless of whether binding is interpreted in terms of IF or CS and has general relevance for the mechanism of zymogen activation of serine proteases. The method also provides a simple test of the validity of IF and CS and indicates when more complex mechanisms of binding should be considered.
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Affiliation(s)
- Enrico Di Cera
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA.
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5
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Blaustein MP, Hamlyn JM. Sensational site: the sodium pump ouabain-binding site and its ligands. Am J Physiol Cell Physiol 2024; 326:C1120-C1177. [PMID: 38223926 DOI: 10.1152/ajpcell.00273.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 12/22/2023] [Accepted: 01/10/2024] [Indexed: 01/16/2024]
Abstract
Cardiotonic steroids (CTS), used by certain insects, toads, and rats for protection from predators, became, thanks to Withering's trailblazing 1785 monograph, the mainstay of heart failure (HF) therapy. In the 1950s and 1960s, we learned that the CTS receptor was part of the sodium pump (NKA) and that the Na+/Ca2+ exchanger was critical for the acute cardiotonic effect of digoxin- and ouabain-related CTS. This "settled" view was upended by seven revolutionary observations. First, subnanomolar ouabain sometimes stimulates NKA while higher concentrations are invariably inhibitory. Second, endogenous ouabain (EO) was discovered in the human circulation. Third, in the DIG clinical trial, digoxin only marginally improved outcomes in patients with HF. Fourth, cloning of NKA in 1985 revealed multiple NKA α and β subunit isoforms that, in the rodent, differ in their sensitivities to CTS. Fifth, the NKA is a cation pump and a hormone receptor/signal transducer. EO binding to NKA activates, in a ligand- and cell-specific manner, several protein kinase and Ca2+-dependent signaling cascades that have widespread physiological effects and can contribute to hypertension and HF pathogenesis. Sixth, all CTS are not equivalent, e.g., ouabain induces hypertension in rodents while digoxin is antihypertensinogenic ("biased signaling"). Seventh, most common rodent hypertension models require a highly ouabain-sensitive α2 NKA and the elevated blood pressure is alleviated by EO immunoneutralization. These numerous phenomena are enabled by NKA's intricate structure. We have just begun to understand the endocrine role of the endogenous ligands and the broad impact of the ouabain-binding site on physiology and pathophysiology.
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Affiliation(s)
- Mordecai P Blaustein
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, United States
| | - John M Hamlyn
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States
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6
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Appavoo SD, Heller NW, van Campenhout CT, Saunders GJ, Yudin AK. Identification of "Structural Pin" Interactions and their Significance for the Conformational Control of Macrocyclic Scaffolds. Angew Chem Int Ed Engl 2024:e202402372. [PMID: 38499461 DOI: 10.1002/anie.202402372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 03/12/2024] [Accepted: 03/18/2024] [Indexed: 03/20/2024]
Abstract
While peptide macrocycles with rigidified conformations have proven to be useful in the design of chemical probes of protein targets, conformational flexibility and rapid interconversion can be equally vital for biological activity and favorable physicochemical properties. This study introduces the concept of "structural pin", which describes a hydrogen bond that is largely responsible for stabilizing the entire macrocycle backbone conformation. Structural analysis of macrocycles using nuclear magnetic resonance (NMR), molecular modelling and X-ray diffraction indicates that disruption of the structural pin can drastically influence the conformation of the entire ring, resulting in novel states with increased flexibility. This finding provides a new tool to interrogate dynamic behaviour of macrocycles. Identification of structural pins offers a useful conceptual framework to understand positions that can either be modified to give flexible structures or retained to maintain the rigidity of the scaffold.
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Affiliation(s)
- Solomon D Appavoo
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6
| | - Nicholas W Heller
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6
| | - Christian T van Campenhout
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6
| | - George J Saunders
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6
| | - Andrei K Yudin
- Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada, M5S 3H6
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7
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Dávalos AL, Rivera Echeverri JD, Favaro DC, Junio de Oliveira R, Penteado Battesini Carretero G, Lacerda C, Midea Cuccovia I, Cangussu Cardoso MV, Farah CS, Kopke Salinas R. Uncovering the Association Mechanism between Two Intrinsically Flexible Proteins. ACS Chem Biol 2024; 19:669-686. [PMID: 38486495 DOI: 10.1021/acschembio.3c00649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
The understanding of protein-protein interaction mechanisms is key to the atomistic description of cell signaling pathways and for the development of new drugs. In this context, the mechanism of intrinsically disordered proteins folding upon binding has attracted attention. The VirB9 C-terminal domain (VirB9Ct) and the VirB7 N-terminal motif (VirB7Nt) associate with VirB10 to form the outer membrane core complex of the Type IV Secretion System injectisome. Despite forming a stable and rigid complex, VirB7Nt behaves as a random coil, while VirB9Ct is intrinsically dynamic in the free state. Here we combined NMR, stopped-flow fluorescence, and computer simulations using structure-based models to characterize the VirB9Ct-VirB7Nt coupled folding and binding mechanism. Qualitative data analysis suggested that VirB9Ct preferentially binds to VirB7Nt by way of a conformational selection mechanism at lower temperatures. However, at higher temperatures, energy barriers between different VirB9Ct conformations are more easily surpassed. Under these conditions the formation of non-native initial encounter complexes may provide alternative pathways toward the native complex conformation. These observations highlight the intimate relationship between folding and binding, calling attention to the fact that the two molecular partners must search for the most favored intramolecular and intermolecular interactions on a rugged and funnelled conformational energy landscape, along which multiple intermediates may lead to the final native state.
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Affiliation(s)
- Angy Liseth Dávalos
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, 05508-000, Brazil
| | | | - Denize C Favaro
- Department of Organic Chemistry, State University of Campinas, Campinas, 13083-862, Brazil
- Structural Biology Initiative, CUNY Advanced Science Research Center, New York, New York 10031, United States
| | - Ronaldo Junio de Oliveira
- Department of Physics, Institute of Exact, Natural and Educational Sciences, Federal University of Triângulo Mineiro, Uberaba, 38064-200, Brazil
| | | | - Caroline Lacerda
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, 05508-000, Brazil
| | - Iolanda Midea Cuccovia
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, 05508-000, Brazil
| | | | - Chuck S Farah
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, 05508-000, Brazil
| | - Roberto Kopke Salinas
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, 05508-000, Brazil
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8
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Xiao Z, Zha J, Yang X, Huang T, Huang S, Liu Q, Wang X, Zhong J, Zheng J, Liang R, Deng Z, Zhang J, Lin S, Dai S. A three-level regulatory mechanism of the aldo-keto reductase subfamily AKR12D. Nat Commun 2024; 15:2128. [PMID: 38459030 PMCID: PMC10923870 DOI: 10.1038/s41467-024-46363-z] [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] [Received: 08/11/2023] [Accepted: 02/23/2024] [Indexed: 03/10/2024] Open
Abstract
Modulation of protein function through allosteric regulation is central in biology, but biomacromolecular systems involving multiple subunits and ligands may exhibit complex regulatory mechanisms at different levels, which remain poorly understood. Here, we discover an aldo-keto reductase termed AKRtyl and present its three-level regulatory mechanism. Specifically, by combining steady-state and transient kinetics, X-ray crystallography and molecular dynamics simulation, we demonstrate that AKRtyl exhibits a positive synergy mediated by an unusual Monod-Wyman-Changeux (MWC) paradigm of allosteric regulation at low concentrations of the cofactor NADPH, but an inhibitory effect at high concentrations is observed. While the substrate tylosin binds at a remote allosteric site with positive cooperativity. We further reveal that these regulatory mechanisms are conserved in AKR12D subfamily, and that substrate cooperativity is common in AKRs across three kingdoms of life. This work provides an intriguing example for understanding complex allosteric regulatory networks.
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Affiliation(s)
- Zhihong Xiao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Jinyin Zha
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Xu Yang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Tingting Huang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Shuxin Huang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Qi Liu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Xiaozheng Wang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Jie Zhong
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
| | - Jianting Zheng
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Rubing Liang
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Zixin Deng
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Jian Zhang
- Medicinal Chemistry and Bioinformatics Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China.
| | - Shuangjun Lin
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
- Haihe Laboratory of Synthetic Biology, Tianjin, 300308, China.
- Frontiers Science Center for Transformative Molecules, Shanghai Jiao Tong University, Shanghai, 200240, China.
| | - Shaobo Dai
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory on Metabolic & Developmental Sciences, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China.
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9
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Hasse T, Mantei E, Shahoei R, Pawnikar S, Wang J, Miao Y, Huang YMM. Mechanistic insights into ligand dissociation from the SARS-CoV-2 spike glycoprotein. PLoS Comput Biol 2024; 20:e1011955. [PMID: 38452125 PMCID: PMC10959368 DOI: 10.1371/journal.pcbi.1011955] [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] [Received: 12/08/2023] [Revised: 03/22/2024] [Accepted: 02/29/2024] [Indexed: 03/09/2024] Open
Abstract
The COVID-19 pandemic, driven by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spurred an urgent need for effective therapeutic interventions. The spike glycoprotein of the SARS-CoV-2 is crucial for infiltrating host cells, rendering it a key candidate for drug development. By interacting with the human angiotensin-converting enzyme 2 (ACE2) receptor, the spike initiates the infection of SARS-CoV-2. Linoleate is known to bind the spike glycoprotein, subsequently reducing its interaction with ACE2. However, the detailed mechanisms underlying the protein-ligand interaction remain unclear. In this study, we characterized the pathways of ligand dissociation and the conformational changes associated with the spike glycoprotein by using ligand Gaussian accelerated molecular dynamics (LiGaMD). Our simulations resulted in eight complete ligand dissociation trajectories, unveiling two distinct ligand unbinding pathways. The preference between these two pathways depends on the gate distance between two α-helices in the receptor binding domain (RBD) and the position of the N-linked glycan at N343. Our study also highlights the essential contributions of K417, N121 glycan, and N165 glycan in ligand unbinding, which are equally crucial in enhancing spike-ACE2 binding. We suggest that the presence of the ligand influences the motions of these residues and glycans, consequently reducing accessibility for spike-ACE2 binding. These findings enhance our understanding of ligand dissociation from the spike glycoprotein and offer significant implications for drug design strategies in the battle against COVID-19.
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Affiliation(s)
- Timothy Hasse
- Department of Physics and Astronomy, Wayne State University, Detroit, Michigan, United States of America
| | - Esra Mantei
- Department of Physics and Astronomy, Wayne State University, Detroit, Michigan, United States of America
| | - Rezvan Shahoei
- Department of Physics and Astronomy, Wayne State University, Detroit, Michigan, United States of America
| | - Shristi Pawnikar
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, United States of America
- Center for Computational Biology, University of Kansas, Lawrence, Kansas, United States of America
| | - Jinan Wang
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, United States of America
- Center for Computational Biology, University of Kansas, Lawrence, Kansas, United States of America
| | - Yinglong Miao
- Department of Molecular Biosciences, University of Kansas, Lawrence, Kansas, United States of America
- Center for Computational Biology, University of Kansas, Lawrence, Kansas, United States of America
| | - Yu-ming M. Huang
- Department of Physics and Astronomy, Wayne State University, Detroit, Michigan, United States of America
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10
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Fröhlich C, Bunzel HA, Buda K, Mulholland AJ, van der Kamp MW, Johnsen PJ, Leiros HKS, Tokuriki N. Epistasis arises from shifting the rate-limiting step during enzyme evolution of a β-lactamase. Nat Catal 2024; 7:499-509. [PMID: 38828429 PMCID: PMC11136654 DOI: 10.1038/s41929-024-01117-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 01/25/2024] [Indexed: 06/05/2024]
Abstract
Epistasis, the non-additive effect of mutations, can provide combinatorial improvements to enzyme activity that substantially exceed the gains from individual mutations. Yet the molecular mechanisms of epistasis remain elusive, undermining our ability to predict pathogen evolution and engineer biocatalysts. Here we reveal how directed evolution of a β-lactamase yielded highly epistatic activity enhancements. Evolution selected four mutations that increase antibiotic resistance 40-fold, despite their marginal individual effects (≤2-fold). Synergistic improvements coincided with the introduction of super-stochiometric burst kinetics, indicating that epistasis is rooted in the enzyme's conformational dynamics. Our analysis reveals that epistasis stemmed from distinct effects of each mutation on the catalytic cycle. The initial mutation increased protein flexibility and accelerated substrate binding, which is rate-limiting in the wild-type enzyme. Subsequent mutations predominantly boosted the chemical steps by fine-tuning substrate interactions. Our work identifies an overlooked cause for epistasis: changing the rate-limiting step can result in substantial synergy that boosts enzyme activity.
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Affiliation(s)
| | - H. Adrian Bunzel
- Department of Biosystem Science and Engineering, ETH Zurich, Basel, Switzerland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, UK
- School of Biochemistry, University of Bristol, Bristol, UK
| | - Karol Buda
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia Canada
| | - Adrian J. Mulholland
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, UK
| | - Marc W. van der Kamp
- Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol, UK
- School of Biochemistry, University of Bristol, Bristol, UK
| | - Pål J. Johnsen
- Department of Pharmacy, UiT The Arctic University of Norway, Tromsø, Norway
| | | | - Nobuhiko Tokuriki
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia Canada
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11
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Nam K, Shao Y, Major DT, Wolf-Watz M. Perspectives on Computational Enzyme Modeling: From Mechanisms to Design and Drug Development. ACS OMEGA 2024; 9:7393-7412. [PMID: 38405524 PMCID: PMC10883025 DOI: 10.1021/acsomega.3c09084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/27/2024]
Abstract
Understanding enzyme mechanisms is essential for unraveling the complex molecular machinery of life. In this review, we survey the field of computational enzymology, highlighting key principles governing enzyme mechanisms and discussing ongoing challenges and promising advances. Over the years, computer simulations have become indispensable in the study of enzyme mechanisms, with the integration of experimental and computational exploration now established as a holistic approach to gain deep insights into enzymatic catalysis. Numerous studies have demonstrated the power of computer simulations in characterizing reaction pathways, transition states, substrate selectivity, product distribution, and dynamic conformational changes for various enzymes. Nevertheless, significant challenges remain in investigating the mechanisms of complex multistep reactions, large-scale conformational changes, and allosteric regulation. Beyond mechanistic studies, computational enzyme modeling has emerged as an essential tool for computer-aided enzyme design and the rational discovery of covalent drugs for targeted therapies. Overall, enzyme design/engineering and covalent drug development can greatly benefit from our understanding of the detailed mechanisms of enzymes, such as protein dynamics, entropy contributions, and allostery, as revealed by computational studies. Such a convergence of different research approaches is expected to continue, creating synergies in enzyme research. This review, by outlining the ever-expanding field of enzyme research, aims to provide guidance for future research directions and facilitate new developments in this important and evolving field.
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Affiliation(s)
- Kwangho Nam
- Department
of Chemistry and Biochemistry, University
of Texas at Arlington, Arlington, Texas 76019, United States
| | - Yihan Shao
- Department
of Chemistry and Biochemistry, University
of Oklahoma, Norman, Oklahoma 73019-5251, United States
| | - Dan T. Major
- Department
of Chemistry and Institute for Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel
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12
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Kovachka S, Panosetti M, Grimaldi B, Azoulay S, Di Giorgio A, Duca M. Small molecule approaches to targeting RNA. Nat Rev Chem 2024; 8:120-135. [PMID: 38278932 DOI: 10.1038/s41570-023-00569-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2023] [Indexed: 01/28/2024]
Abstract
The development of innovative methodologies to identify RNA binders has attracted enormous attention in chemical biology and drug discovery. Although antibiotics targeting bacterial ribosomal RNA have been on the market for decades, the renewed interest in RNA targeting reflects the need to better understand complex intracellular processes involving RNA. In this context, small molecules are privileged tools used to explore the biological functions of RNA and to validate RNAs as therapeutic targets, and they eventually are to become new drugs. Despite recent progress, the rational design of specific RNA binders requires a better understanding of the interactions which occur with the RNA target to reach the desired biological response. In this Review, we discuss the challenges to approaching this underexplored chemical space, together with recent strategies to bind, interact and affect biologically relevant RNAs.
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Affiliation(s)
- Sandra Kovachka
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
| | - Marc Panosetti
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
- Molecular Medicine Research Line, Istituto Italiano di Tecnologia (IIT), Genoa, Italy
| | - Benedetto Grimaldi
- Molecular Medicine Research Line, Istituto Italiano di Tecnologia (IIT), Genoa, Italy
| | - Stéphane Azoulay
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
| | - Audrey Di Giorgio
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France
| | - Maria Duca
- Université Côte d'Azur, CNRS, Institute of Chemistry of Nice, Nice, France.
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13
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Nam K, Arattu Thodika AR, Grundström C, Sauer UH, Wolf-Watz M. Elucidating Dynamics of Adenylate Kinase from Enzyme Opening to Ligand Release. J Chem Inf Model 2024; 64:150-163. [PMID: 38117131 PMCID: PMC10778088 DOI: 10.1021/acs.jcim.3c01618] [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] [Received: 10/06/2023] [Revised: 12/01/2023] [Accepted: 12/07/2023] [Indexed: 12/21/2023]
Abstract
This study explores ligand-driven conformational changes in adenylate kinase (AK), which is known for its open-to-close conformational transitions upon ligand binding and release. By utilizing string free energy simulations, we determine the free energy profiles for both enzyme opening and ligand release and compare them with profiles from the apoenzyme. Results reveal a three-step ligand release process, which initiates with the opening of the adenosine triphosphate-binding subdomain (ATP lid), followed by ligand release and concomitant opening of the adenosine monophosphate-binding subdomain (AMP lid). The ligands then transition to nonspecific positions before complete dissociation. In these processes, the first step is energetically driven by ATP lid opening, whereas the second step is driven by ATP release. In contrast, the AMP lid opening and its ligand release make minor contributions to the total free energy for enzyme opening. Regarding the ligand binding mechanism, our results suggest that AMP lid closure occurs via an induced-fit mechanism triggered by AMP binding, whereas ATP lid closure follows conformational selection. This difference in the closure mechanisms provides an explanation with implications for the debate on ligand-driven conformational changes of AK. Additionally, we determine an X-ray structure of an AK variant that exhibits significant rearrangements in the stacking of catalytic arginines, explaining its reduced catalytic activity. In the context of apoenzyme opening, the sequence of events is different. Here, the AMP lid opens first while the ATP lid remains closed, and the free energy associated with ATP lid opening varies with orientation, aligning with the reported AK opening and closing rate heterogeneity. Finally, this study, in conjunction with our previous research, provides a comprehensive view of the intricate interplay between various structural elements, ligands, and catalytic residues that collectively contribute to the robust catalytic power of the enzyme.
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Affiliation(s)
- Kwangho Nam
- Department
of Chemistry and Biochemistry, University
of Texas at Arlington, Arlington, Texas 76019, United States
| | - Abdul Raafik Arattu Thodika
- Department
of Chemistry and Biochemistry, University
of Texas at Arlington, Arlington, Texas 76019, United States
| | | | - Uwe H. Sauer
- Department
of Chemistry, Umeå University, Umeå 90187, SE, Sweden
| | - Magnus Wolf-Watz
- Department
of Chemistry, Umeå University, Umeå 90187, SE, Sweden
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14
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Hariri AA, Cartwright AP, Dory C, Gidi Y, Yee S, Thompson IAP, Fu KX, Yang K, Wu D, Maganzini N, Feagin T, Young BE, Afshar BH, Eisenstein M, Digonnet MJF, Vuckovic J, Soh HT. Modular Aptamer Switches for the Continuous Optical Detection of Small-Molecule Analytes in Complex Media. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2304410. [PMID: 37975267 DOI: 10.1002/adma.202304410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 11/10/2023] [Indexed: 11/19/2023]
Abstract
Aptamers are a promising class of affinity reagents because signal transduction mechanisms can be built into the reagent, so that they can directly produce a physically measurable output signal upon target binding. However, endowing the signal transduction functionality into an aptamer remains a trial-and-error process that can compromise its affinity or specificity and typically requires knowledge of the ligand binding domain or its structure. In this work, a design architecture that can convert an existing aptamer into a "reversible aptamer switch" whose kinetic and thermodynamic properties can be tuned without a priori knowledge of the ligand binding domain or its structure is described. Finally, by combining these aptamer switches with evanescent-field-based optical detection hardware that minimizes sample autofluorescence, this study demonstrates the first optical biosensor system that can continuously measure multiple biomarkers (dopamine and cortisol) in complex samples (artificial cerebrospinal fluid and undiluted plasma) with second and subsecond-scale time responses at physiologically relevant concentration ranges.
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Affiliation(s)
- Amani A Hariri
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Alyssa P Cartwright
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Constantin Dory
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Yasser Gidi
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Steven Yee
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Ian A P Thompson
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Kaiyu X Fu
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Kiyoul Yang
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Diana Wu
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
| | - Nicolò Maganzini
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Trevor Feagin
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Brian E Young
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
| | - Behrad Habib Afshar
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | | | - Michel J F Digonnet
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Jelena Vuckovic
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - H Tom Soh
- Department of Radiology, Stanford University, Stanford, CA, 94305, USA
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
- Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA
- Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA
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15
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Asadollahi K, Rajput S, de Zhang LA, Ang CS, Nie S, Williamson NA, Griffin MDW, Bathgate RAD, Scott DJ, Weikl TR, Jameson GNL, Gooley PR. Unravelling the mechanism of neurotensin recognition by neurotensin receptor 1. Nat Commun 2023; 14:8155. [PMID: 38071229 PMCID: PMC10710507 DOI: 10.1038/s41467-023-44010-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 11/26/2023] [Indexed: 12/18/2023] Open
Abstract
The conformational ensembles of G protein-coupled receptors (GPCRs) include inactive and active states. Spectroscopy techniques, including NMR, show that agonists, antagonists and other ligands shift the ensemble toward specific states depending on the pharmacological efficacy of the ligand. How receptors recognize ligands and the kinetic mechanism underlying this population shift is poorly understood. Here, we investigate the kinetic mechanism of neurotensin recognition by neurotensin receptor 1 (NTS1) using 19F-NMR, hydrogen-deuterium exchange mass spectrometry and stopped-flow fluorescence spectroscopy. Our results indicate slow-exchanging conformational heterogeneity on the extracellular surface of ligand-bound NTS1. Numerical analysis of the kinetic data of neurotensin binding to NTS1 shows that ligand recognition follows an induced-fit mechanism, in which conformational changes occur after neurotensin binding. This approach is applicable to other GPCRs to provide insight into the kinetic regulation of ligand recognition by GPCRs.
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Affiliation(s)
- Kazem Asadollahi
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
- The Florey, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Sunnia Rajput
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Lazarus Andrew de Zhang
- The Florey, University of Melbourne, Parkville, VIC, 3010, Australia
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC, 3052, Australia
| | - Ching-Seng Ang
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Shuai Nie
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Nicholas A Williamson
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Michael D W Griffin
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, VIC, 3010, Australia
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Ross A D Bathgate
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, VIC, 3010, Australia
- The Florey, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Daniel J Scott
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, VIC, 3010, Australia
- The Florey, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Thomas R Weikl
- Department of Biomolecular Systems, Max Planck Institute of Colloids and Interfaces, 14476, Potsdam, Germany
| | - Guy N L Jameson
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia
- School of Chemistry, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Paul R Gooley
- Department of Biochemistry and Pharmacology, University of Melbourne, Parkville, VIC, 3010, Australia.
- Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, 3010, Australia.
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16
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Roy M, Horovitz A. Distinguishing between concerted, sequential and barrierless conformational changes: Folding versus allostery. Curr Opin Struct Biol 2023; 83:102721. [PMID: 37922762 DOI: 10.1016/j.sbi.2023.102721] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 09/26/2023] [Indexed: 11/07/2023]
Abstract
Characterization of transition and intermediate states of reactions provides insights into their mechanisms and is often achieved through analysis of linear free energy relationships. Such an approach has been used extensively in protein folding studies but less so for analyzing allosteric transitions. Here, we point out analogies in ways to characterize pathways and intermediates in folding and allosteric transitions. Achieving an understanding of the mechanisms by which proteins undergo allosteric switching is important in many cases for obtaining insights into how they function.
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Affiliation(s)
- Mousam Roy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Amnon Horovitz
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot 7610001, Israel.
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17
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Hofmann H. All over or overall - Do we understand allostery? Curr Opin Struct Biol 2023; 83:102724. [PMID: 37898005 DOI: 10.1016/j.sbi.2023.102724] [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] [Received: 07/20/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 10/30/2023]
Abstract
Allostery is probably the most important concept in the regulation of cellular processes. Models to explain allostery are plenty. Each sheds light on different aspects but their entirety conveys an ambiguous feeling of comprehension and disappointment. Here, I discuss the most popular allostery models, their roots, similarities, and limitations. All of them are thermodynamic models. Naturally this bears a certain degree of redundancy, which forms the center of this review. After sixty years, many questions remain unanswered, mainly because our human longing for causality as base for understanding is not satisfied by thermodynamics alone. A description of allostery in terms of pathways, i.e., as a temporal chain of events, has been-, and still is-, a missing piece of the puzzle.
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Affiliation(s)
- Hagen Hofmann
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Herzl St. 234, 76100 Rehovot, Israel.
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18
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Sweeney DT, Zárate-Pérez F, Stokowa-Sołtys K, Hackett JC. Induced Fit Describes Ligand Binding to Membrane-Associated Cytochrome P450 3A4. Mol Pharmacol 2023; 104:154-163. [PMID: 37536953 PMCID: PMC10506697 DOI: 10.1124/molpharm.123.000698] [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] [Received: 03/14/2023] [Revised: 07/06/2023] [Accepted: 07/20/2023] [Indexed: 08/05/2023] Open
Abstract
Cytochrome P450 3A4 (CYP3A4) is the dominant P450 involved in human xenobiotic metabolism. Competition for CYP3A4 therefore underlies several adverse drug-drug interactions. Despite its clinical significance, the mechanisms CYP3A4 uses to bind diverse ligands remain poorly understood. Highly monodisperse CYP3A4 embedded in anionic lipoprotein nanodiscs containing an equal mixture of 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) were used to determine which of the limiting kinetic schemes that include protein conformational change, conformational selection (CS) or induced fit (IF), best described the binding of four known irreversible inhibitors. Azamulin, retapamulin, pleuromutilin, and mibrefadil binding to CYP3A4 nanodiscs conformed to a single-site binding model. Exponential fits of stopped-flow UV-visible absorption spectroscopy data supported multiple-step binding mechanisms. Trends in the rates of relaxation to equilibrium with increasing ligand concentrations were ambiguous as to whether IF or CS was involved; however, global fitting and consideration of the rate constants favored an IF mechanism. In the case of mibrefadil, a transient complex was observed in the stopped-flow UV-visible experiment, definitively assigning the presence of IF in ligand binding. While these studies only consider a small region of CYP3A4's vast ligand space, they provide kinetic evidence that CYP3A4 can use an IF mechanism. SIGNIFICANCE STATEMENT: CYP3A4 is capable of oxidizing numerous xenobiotics, including many drugs. Such promiscuity could not be achieved without conformational changes to accommodate diverse substrates. It is unknown whether conformational heterogeneity is present before (conformational selection) or after (induced fit) ligand binding. Stopped-flow measurements of suicide inhibitors binding to nanodisc-embedded CYP3A4 combined with sophisticated numerical analyses support that induced fit better describes ligand binding to this important enzyme.
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Affiliation(s)
- David Tyler Sweeney
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, Miami, Florida (J.C.H., K.S.S., F.Z.P.); Department of Physiology and Biophysics and The Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia (D.T.S.); and Department of Biological and Medicinal Chemistry, Faculty of Chemistry, University of Wroclaw, Wroclaw, Poland (K.S.S.)
| | - Francisco Zárate-Pérez
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, Miami, Florida (J.C.H., K.S.S., F.Z.P.); Department of Physiology and Biophysics and The Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia (D.T.S.); and Department of Biological and Medicinal Chemistry, Faculty of Chemistry, University of Wroclaw, Wroclaw, Poland (K.S.S.)
| | - Kamila Stokowa-Sołtys
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, Miami, Florida (J.C.H., K.S.S., F.Z.P.); Department of Physiology and Biophysics and The Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia (D.T.S.); and Department of Biological and Medicinal Chemistry, Faculty of Chemistry, University of Wroclaw, Wroclaw, Poland (K.S.S.)
| | - John C Hackett
- Department of Chemistry and Biochemistry and Biomolecular Sciences Institute, Florida International University, Miami, Florida (J.C.H., K.S.S., F.Z.P.); Department of Physiology and Biophysics and The Massey Cancer Center, Virginia Commonwealth University, Richmond, Virginia (D.T.S.); and Department of Biological and Medicinal Chemistry, Faculty of Chemistry, University of Wroclaw, Wroclaw, Poland (K.S.S.)
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19
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Roy M, Fleisher RC, Alexandrov AI, Horovitz A. Reduced ADP off-rate by the yeast CCT2 double mutation T394P/R510H which causes Leber congenital amaurosis in humans. Commun Biol 2023; 6:888. [PMID: 37644231 PMCID: PMC10465592 DOI: 10.1038/s42003-023-05261-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Accepted: 08/20/2023] [Indexed: 08/31/2023] Open
Abstract
The CCT/TRiC chaperonin is found in the cytosol of all eukaryotic cells and assists protein folding in an ATP-dependent manner. The heterozygous double mutation T400P and R516H in subunit CCT2 is known to cause Leber congenital amaurosis (LCA), a hereditary congenital retinopathy. This double mutation also renders the function of subunit CCT2, when it is outside of the CCT/TRiC complex, to be defective in promoting autophagy. Here, we show using steady-state and transient kinetic analysis that the corresponding double mutation in subunit CCT2 from Saccharomyces cerevisiae reduces the off-rate of ADP during ATP hydrolysis by CCT/TRiC. We also report that the ATPase activity of CCT/TRiC is stimulated by a non-folded substrate. Our results suggest that the closed state of CCT/TRiC is stabilized by the double mutation owing to the slower off-rate of ADP, thereby impeding the exit of CCT2 from the complex that is required for its function in autophagy.
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Affiliation(s)
- Mousam Roy
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Rachel C Fleisher
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Alexander I Alexandrov
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, 7610001, Israel
| | - Amnon Horovitz
- Department of Chemical and Structural Biology, Weizmann Institute of Science, Rehovot, 7610001, Israel.
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20
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Liu W, Chen L, Yin D, Yang Z, Feng J, Sun Q, Lai L, Guo X. Visualizing single-molecule conformational transition and binding dynamics of intrinsically disordered proteins. Nat Commun 2023; 14:5203. [PMID: 37626077 PMCID: PMC10457384 DOI: 10.1038/s41467-023-41018-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 08/21/2023] [Indexed: 08/27/2023] Open
Abstract
Intrinsically disordered proteins (IDPs) play crucial roles in cellular processes and hold promise as drug targets. However, the dynamic nature of IDPs remains poorly understood. Here, we construct a single-molecule electrical nanocircuit based on silicon nanowire field-effect transistors (SiNW-FETs) and functionalize it with an individual disordered c-Myc bHLH-LZ domain to enable label-free, in situ, and long-term measurements at the single-molecule level. We use the device to study c-Myc interaction with Max and/or small molecule inhibitors. We observe the self-folding/unfolding process of c-Myc and reveal its interaction mechanism with Max and inhibitors through ultrasensitive real-time monitoring. We capture a relatively stable encounter intermediate ensemble of c-Myc during its transition from the unbound state to the fully folded state. The c-Myc/Max and c-Myc/inhibitor dissociation constants derived are consistent with other ensemble experiments. These proof-of-concept results provide an understanding of the IDP-binding/folding mechanism and represent a promising nanotechnology for IDP conformation/interaction studies and drug discovery.
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Affiliation(s)
- Wenzhe Liu
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China
| | - Limin Chen
- Peking-Tsinghua Center for Life Sciences, Peking University, 100871, Beijing, P. R. China
| | - Dongbao Yin
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China
| | - Zhiheng Yang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China
| | - Jianfei Feng
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China
| | - Qi Sun
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China.
| | - Luhua Lai
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China.
- Peking-Tsinghua Center for Life Sciences, Peking University, 100871, Beijing, P. R. China.
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, 100871, Beijing, P. R. China.
| | - Xuefeng Guo
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 292 Chengfu Road, Haidian District, 100871, Beijing, P. R. China.
- Center of Single-Molecule Sciences, Institute of Modern Optics, Frontiers Science Center for New Organic Matter, College of Electronic Information and Optical Engineering, Nankai University, 38 Tongyan Road, Jinnan District, 300350, Tianjin, P. R. China.
- National Biomedical Imaging Center, Peking University, Beijing, 100871, P. R. China.
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21
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Chen KW, Sun TY, Wu YD. New Insights into the Cooperativity and Dynamics of Dimeric Enzymes. Chem Rev 2023; 123:9940-9981. [PMID: 37561162 DOI: 10.1021/acs.chemrev.3c00042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
A survey of protein databases indicates that the majority of enzymes exist in oligomeric forms, with about half of those found in the UniProt database being homodimeric. Understanding why many enzymes are in their dimeric form is imperative. Recent developments in experimental and computational techniques have allowed for a deeper comprehension of the cooperative interactions between the subunits of dimeric enzymes. This review aims to succinctly summarize these recent advancements by providing an overview of experimental and theoretical methods, as well as an understanding of cooperativity in substrate binding and the molecular mechanisms of cooperative catalysis within homodimeric enzymes. Focus is set upon the beneficial effects of dimerization and cooperative catalysis. These advancements not only provide essential case studies and theoretical support for comprehending dimeric enzyme catalysis but also serve as a foundation for designing highly efficient catalysts, such as dimeric organic catalysts. Moreover, these developments have significant implications for drug design, as exemplified by Paxlovid, which was designed for the homodimeric main protease of SARS-CoV-2.
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Affiliation(s)
- Ke-Wei Chen
- Lab of Computional Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Tian-Yu Sun
- Shenzhen Bay Laboratory, Shenzhen 518132, China
| | - Yun-Dong Wu
- Lab of Computional Chemistry and Drug Design, State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China
- Shenzhen Bay Laboratory, Shenzhen 518132, China
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22
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Kim JH, Pandit N, Yoo M, Park TH, Choi JU, Park CH, Jung KY, Lee BI. Crystal structure of [1,2,4]triazolo[4,3-b]pyridazine derivatives as BRD4 bromodomain inhibitors and structure-activity relationship study. Sci Rep 2023; 13:10805. [PMID: 37402749 DOI: 10.1038/s41598-023-37527-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 06/22/2023] [Indexed: 07/06/2023] Open
Abstract
BRD4 contains two tandem bromodomains (BD1 and BD2) that recognize acetylated lysine for epigenetic reading, and these bromodomains are promising therapeutic targets for treating various diseases, including cancers. BRD4 is a well-studied target, and many chemical scaffolds for inhibitors have been developed. Research on the development of BRD4 inhibitors against various diseases is actively being conducted. Herein, we propose a series of [1,2,4]triazolo[4,3-b]pyridazine derivatives as bromodomain inhibitors with micromolar IC50 values. We characterized the binding modes by determining the crystal structures of BD1 in complex with four selected inhibitors. Compounds containing [1,2,4] triazolo[4,3-b]pyridazine derivatives offer promising starting molecules for designing potent BRD4 BD inhibitors.
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Affiliation(s)
- Jung-Hoon Kim
- Research Institute, National Cancer Center, Goyang, Gyeonggi, 10408, Republic of Korea
- Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy, Goyang, Gyeonggi, 10408, Republic of Korea
| | - Navin Pandit
- Department of Medicinal Chemistry and Pharmacology, University of Science and Technology, Daejeon, 34113, Republic of Korea
| | - Miyoun Yoo
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea
| | - Tae Hyun Park
- Department of Anesthesiology, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Ji U Choi
- Department of Medicinal Chemistry and Pharmacology, University of Science and Technology, Daejeon, 34113, Republic of Korea
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea
| | - Chi Hoon Park
- Department of Medicinal Chemistry and Pharmacology, University of Science and Technology, Daejeon, 34113, Republic of Korea.
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea.
| | - Kwan-Young Jung
- Department of Medicinal Chemistry and Pharmacology, University of Science and Technology, Daejeon, 34113, Republic of Korea.
- Therapeutics and Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea.
| | - Byung Il Lee
- Research Institute, National Cancer Center, Goyang, Gyeonggi, 10408, Republic of Korea.
- Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy, Goyang, Gyeonggi, 10408, Republic of Korea.
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23
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Redhair M, Nath A, Hackett JC, Atkins WM. Low molecular weight ligands bind to CYP3A4 via a branched induced fit mechanism: Implications for O 2 binding. Arch Biochem Biophys 2023; 739:109582. [PMID: 36948348 PMCID: PMC10103683 DOI: 10.1016/j.abb.2023.109582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 03/03/2023] [Accepted: 03/19/2023] [Indexed: 03/24/2023]
Affiliation(s)
- Michelle Redhair
- Department of Medicinal Chemistry, Box 357610, University of Washington, Seattle, WA, 98195-7610, USA
| | - Abhinav Nath
- Department of Medicinal Chemistry, Box 357610, University of Washington, Seattle, WA, 98195-7610, USA
| | - John C Hackett
- Department of Chemistry & Biochemistry, Florida International University, 11200 SW 8th St., Miami, FL, 33199, USA
| | - William M Atkins
- Department of Medicinal Chemistry, Box 357610, University of Washington, Seattle, WA, 98195-7610, USA.
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24
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Foroutannejad S, Good LL, Lin C, Carter ZI, Tadesse MG, Lucius AL, Crane BR, Maillard RA. The cofactor-dependent folding mechanism of Drosophila cryptochrome revealed by single-molecule pulling experiments. Nat Commun 2023; 14:1057. [PMID: 36828841 PMCID: PMC9958137 DOI: 10.1038/s41467-023-36701-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 02/10/2023] [Indexed: 02/26/2023] Open
Abstract
The link between cofactor binding and protein activity is well-established. However, how cofactor interactions modulate folding of large proteins remains unknown. We use optical tweezers, clustering and global fitting to dissect the folding mechanism of Drosophila cryptochrome (dCRY), a 542-residue protein that binds FAD, one of the most chemically and structurally complex cofactors in nature. We show that the first dCRY parts to fold are independent of FAD, but later steps are FAD-driven as the remaining polypeptide folds around the cofactor. FAD binds to largely unfolded intermediates, yet with association kinetics above the diffusion-limit. Interestingly, not all FAD moieties are required for folding: whereas the isoalloxazine ring linked to ribitol and one phosphate is sufficient to drive complete folding, the adenosine ring with phosphates only leads to partial folding. Lastly, we propose a dCRY folding model where regions that undergo conformational transitions during signal transduction are the last to fold.
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Affiliation(s)
| | - Lydia L Good
- Department of Chemistry, Georgetown University, Washington, DC, USA
| | - Changfan Lin
- Department of Chemistry & Chemical Biology, Cornell University, Ithaca, NY, USA
| | - Zachariah I Carter
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Mahlet G Tadesse
- Department of Mathematics and Statistics, Georgetown University, Washington, DC, USA
| | - Aaron L Lucius
- Department of Chemistry, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Brian R Crane
- Department of Chemistry & Chemical Biology, Cornell University, Ithaca, NY, USA
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25
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Vauquelin G, Maes D. Competition in drug binding and … the race to equilibrium. Fundam Clin Pharmacol 2023; 37:147-157. [PMID: 35981720 DOI: 10.1111/fcp.12824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 06/30/2022] [Accepted: 08/17/2022] [Indexed: 01/25/2023]
Abstract
Binding kinetics has become a popular topic in pharmacology due to its potential contribution to the selectivity and duration of drug action. Yet, the overall kinetic aspects of complex binding mechanisms are still merely described in terms of elaborate algebraic equations. Interestingly, it has been recommended some 10 years ago to examine such mechanisms in terms of binding fluxes instead of the conventional rate constants. Alike the velocity of product formation in enzymology, those fluxes refer to the velocity by which one target species converts into another one. Novel binding flux-based approaches are utilized to get a better visual insight into the "competition" between two drugs/ligands for a single target as well as between induced fit- and conformational selection pathways for a single ligand within a thermodynamic cycle. The present data were obtained by differential equation-based simulations. Early on, the ligand-binding steps "race" to equilibrium (i.e., when their forward and reverse fluxes are equal) at their individual pace. The overall/global equilibrium is only reached later on. For the competition association assays, this parting might produce a transient "overshoot" of one of the bound target species. A similar overshoot may also show up within a thermodynamic cycle and, at first glance, suggest that the induced fit pathway dominates. Yet, present findings show that under certain circumstances, it could rather be the other way round. Novel binding flux-based approaches offer visually attractive insights into crucial aspects of "complex" binding mechanisms under non-equilibrium conditions.
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Affiliation(s)
- Georges Vauquelin
- Department of Molecular and Biochemical Pharmacology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Dominique Maes
- Structural Biology Brussels, Vrije Universiteit Brussel, Brussels, Belgium
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26
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Integration of smart nanomaterials for highly selective disposable sensors and their forensic applications in amphetamine determination. Electrochim Acta 2023. [DOI: 10.1016/j.electacta.2023.142009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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27
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Meller A, Lotthammer JM, Smith LG, Novak B, Lee LA, Kuhn CC, Greenberg L, Leinwand LA, Greenberg MJ, Bowman GR. Drug specificity and affinity are encoded in the probability of cryptic pocket opening in myosin motor domains. eLife 2023; 12:83602. [PMID: 36705568 PMCID: PMC9995120 DOI: 10.7554/elife.83602] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 01/23/2023] [Indexed: 01/28/2023] Open
Abstract
The design of compounds that can discriminate between closely related target proteins remains a central challenge in drug discovery. Specific therapeutics targeting the highly conserved myosin motor family are urgently needed as mutations in at least six of its members cause numerous diseases. Allosteric modulators, like the myosin-II inhibitor blebbistatin, are a promising means to achieve specificity. However, it remains unclear why blebbistatin inhibits myosin-II motors with different potencies given that it binds at a highly conserved pocket that is always closed in blebbistatin-free experimental structures. We hypothesized that the probability of pocket opening is an important determinant of the potency of compounds like blebbistatin. To test this hypothesis, we used Markov state models (MSMs) built from over 2 ms of aggregate molecular dynamics simulations with explicit solvent. We find that blebbistatin's binding pocket readily opens in simulations of blebbistatin-sensitive myosin isoforms. Comparing these conformational ensembles reveals that the probability of pocket opening correctly identifies which isoforms are most sensitive to blebbistatin inhibition and that docking against MSMs quantitatively predicts blebbistatin binding affinities (R2=0.82). In a blind prediction for an isoform (Myh7b) whose blebbistatin sensitivity was unknown, we find good agreement between predicted and measured IC50s (0.67 μM vs. 0.36 μM). Therefore, we expect this framework to be useful for the development of novel specific drugs across numerous protein targets.
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Affiliation(s)
- Artur Meller
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
- Medical Scientist Training Program, Washington University in St. LouisPhiladelphiaUnited States
| | - Jeffrey M Lotthammer
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
| | - Louis G Smith
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
- Department of Biochemistry and Biophysics, University of PennsylvaniaPhiladelphiaUnited States
| | - Borna Novak
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
- Medical Scientist Training Program, Washington University in St. LouisPhiladelphiaUnited States
| | - Lindsey A Lee
- Molecular, Cellular, and Developmental Biology Department, University of Colorado BoulderBoulderUnited States
- BioFrontiers InstituteBoulderUnited States
| | - Catherine C Kuhn
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
| | - Lina Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
| | - Leslie A Leinwand
- Molecular, Cellular, and Developmental Biology Department, University of Colorado BoulderBoulderUnited States
- BioFrontiers InstituteBoulderUnited States
| | - Michael J Greenberg
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
| | - Gregory R Bowman
- Department of Biochemistry and Molecular Biophysics, Washington University in St. LouisSt LouisUnited States
- Department of Biochemistry and Biophysics, University of PennsylvaniaPhiladelphiaUnited States
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28
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Sung HL, Nesbitt DJ. Ligand-Dependent Volumetric Characterization of Manganese Riboswitch Folding: A High-Pressure Single-Molecule Kinetic Study. J Phys Chem B 2022; 126:9781-9789. [PMID: 36399551 DOI: 10.1021/acs.jpcb.2c06579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Nanoscopic differences in free volume result in pressure-dependent changes in free energies which can therefore impact folding/unfolding stability of biomolecules. Although such effects are typically insignificant under ambient pressure conditions, they are crucially important for deep ocean marine life, where the hydraulic pressure can be on the kilobar scale. In this work, single molecule FRET spectroscopy is used to study the effects of pressure on both the kinetics and overall thermodynamics for folding/unfolding of the manganese riboswitch. Detailed pressure-dependent analysis of the conformational kinetics allows one to extract precision changes (σ ≲ 4-8 Å3) in free volumes not only between the fully folded/unfolded conformations but also with respect to the folding transition state of the manganese riboswitch. This permits first extraction of a novel "reversible work" free energy (PΔV) landscape, which reveals a monotonic increase in manganese riboswitch volume along the folding coordinate. Furthermore, such a tool permits exploration of pressure-dependent effects on both Mn2+ binding and riboswitch folding, which demonstrate that ligand attachment stabilizes the riboswitch under pressure by decreasing the volume increase upon folding (ΔΔV < 0). Such competition between ligand binding and pressure-induced denaturation dynamics could be of significant evolutionary advantage, compensating for a weakening in riboswitch tertiary structure with pressure-mediated ligand binding and promotion of folding response.
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Affiliation(s)
- Hsuan-Lei Sung
- JILA, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309, United States.,Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States
| | - David J Nesbitt
- JILA, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309, United States.,Department of Chemistry, University of Colorado, Boulder, Colorado 80309, United States.,Department of Physics, University of Colorado, Boulder, Colorado 80309, United States
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29
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Fukunishi Y, Higo J, Kasahara K. Computer simulation of molecular recognition in biomolecular system: from in silico screening to generalized ensembles. Biophys Rev 2022; 14:1423-1447. [PMID: 36465086 PMCID: PMC9703445 DOI: 10.1007/s12551-022-01015-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 11/06/2022] [Indexed: 11/29/2022] Open
Abstract
Prediction of ligand-receptor complex structure is important in both the basic science and the industry such as drug discovery. We report various computation molecular docking methods: fundamental in silico (virtual) screening, ensemble docking, enhanced sampling (generalized ensemble) methods, and other methods to improve the accuracy of the complex structure. We explain not only the merits of these methods but also their limits of application and discuss some interaction terms which are not considered in the in silico methods. In silico screening and ensemble docking are useful when one focuses on obtaining the native complex structure (the most thermodynamically stable complex). Generalized ensemble method provides a free-energy landscape, which shows the distribution of the most stable complex structure and semi-stable ones in a conformational space. Also, barriers separating those stable structures are identified. A researcher should select one of the methods according to the research aim and depending on complexity of the molecular system to be studied.
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Affiliation(s)
- Yoshifumi Fukunishi
- Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 2-3-26, Aomi, Koto-Ku, Tokyo, 135-0064 Japan
| | - Junichi Higo
- Graduate School of Information Science, University of Hyogo, 7-1-28 Minatojima Minamimachi, Chuo-Ku, Kobe, Hyogo 650-0047 Japan ,Research Organization of Science and Technology, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577 Japan
| | - Kota Kasahara
- College of Life Sciences, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577 Japan
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30
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Wu F, Jin S, Jiang Y, Jin X, Tang B, Niu Z, Liu X, Zhang Q, Zeng X, Li SZ. Pre-Training of Equivariant Graph Matching Networks with Conformation Flexibility for Drug Binding. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2203796. [PMID: 36202759 PMCID: PMC9685463 DOI: 10.1002/advs.202203796] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 09/07/2022] [Indexed: 05/16/2023]
Abstract
The latest biological findings observe that the motionless "lock-and-key" theory is not generally applicable and that changes in atomic sites and binding pose can provide important information for understanding drug binding. However, the computational expenditure limits the growth of protein trajectory-related studies, thus hindering the possibility of supervised learning. A spatial-temporal pre-training method based on the modified equivariant graph matching networks, dubbed ProtMD which has two specially designed self-supervised learning tasks: atom-level prompt-based denoising generative task and conformation-level snapshot ordering task to seize the flexibility information inside molecular dynamics (MD) trajectories with very fine temporal resolutions is presented. The ProtMD can grant the encoder network the capacity to capture the time-dependent geometric mobility of conformations along MD trajectories. Two downstream tasks are chosen to verify the effectiveness of ProtMD through linear detection and task-specific fine-tuning. A huge improvement from current state-of-the-art methods, with a decrease of 4.3% in root mean square error for the binding affinity problem and an average increase of 13.8% in the area under receiver operating characteristic curve and the area under the precision-recall curve for the ligand efficacy problem is observed. The results demonstrate a strong correlation between the magnitude of conformation's motion in the 3D space and the strength with which the ligand binds with its receptor.
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Affiliation(s)
- Fang Wu
- School of EngineeringWestlake UniversityHangzhou310024China
- MindRank AI Ltd.Hangzhou310000China
| | - Shuting Jin
- MindRank AI Ltd.Hangzhou310000China
- School of InformaticsXiamen UniversityXiamen361005China
| | | | | | | | | | - Xiangrong Liu
- School of InformaticsXiamen UniversityXiamen361005China
| | - Qiang Zhang
- ZJU‐Hangzhou Global Scientific and Technological Innovation CenterHangzhou311200China
- College of Computer Science and TechnologyZhejiang UniversityHangzhou310013China
| | - Xiangxiang Zeng
- School of Information Science and EngineeringHunan UniversityHunan410082China
| | - Stan Z. Li
- School of EngineeringWestlake UniversityHangzhou310024China
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31
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Mollica L, Cupaioli FA, Rossetti G, Chiappori F. An overview of structural approaches to study therapeutic RNAs. Front Mol Biosci 2022; 9:1044126. [PMID: 36387283 PMCID: PMC9649582 DOI: 10.3389/fmolb.2022.1044126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 10/18/2022] [Indexed: 11/07/2023] Open
Abstract
RNAs provide considerable opportunities as therapeutic agent to expand the plethora of classical therapeutic targets, from extracellular and surface proteins to intracellular nucleic acids and its regulators, in a wide range of diseases. RNA versatility can be exploited to recognize cell types, perform cell therapy, and develop new vaccine classes. Therapeutic RNAs (aptamers, antisense nucleotides, siRNA, miRNA, mRNA and CRISPR-Cas9) can modulate or induce protein expression, inhibit molecular interactions, achieve genome editing as well as exon-skipping. A common RNA thread, which makes it very promising for therapeutic applications, is its structure, flexibility, and binding specificity. Moreover, RNA displays peculiar structural plasticity compared to proteins as well as to DNA. Here we summarize the recent advances and applications of therapeutic RNAs, and the experimental and computational methods to analyze their structure, by biophysical techniques (liquid-state NMR, scattering, reactivity, and computational simulations), with a focus on dynamic and flexibility aspects and to binding analysis. This will provide insights on the currently available RNA therapeutic applications and on the best techniques to evaluate its dynamics and reactivity.
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Affiliation(s)
- Luca Mollica
- Department of Medical Biotechnologies and Translational Medicine, L.I.T.A/University of Milan, Milan, Italy
| | | | | | - Federica Chiappori
- National Research Council—Institute for Biomedical Technologies, Milan, Italy
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32
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Bie L, Wang Y, Jiang F, Xiao Z, Zhang L, Wang J. Insights into the binding mode of AS1411 aptamer to nucleolin. Front Mol Biosci 2022; 9:1025313. [PMID: 36262475 PMCID: PMC9574071 DOI: 10.3389/fmolb.2022.1025313] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 09/20/2022] [Indexed: 11/23/2022] Open
Abstract
AS1411 aptamer can function as a recognition probe to detect the cell surface nucleolin overexpressed in cancer cells, however, little is known about their binding process. This study proposed a feasible binding mode for the first time and provided atomic-level descriptions for the high affinity and specific binding of AS1411. The binding pose predicted by docking was screened using knowledge-based criteria, and a microsecond molecular dynamics (MD) simulation showed the stable existence of the predicted structure in the solution. Structural analysis shows that the unique capping of the 5′ end of AS1411 provides the specific binding with RBD1, and the interactions of hydrogen bond, salt bridge, and water-mediated network between AS1411 and RBD1,2 stabilize the binding. The calculation of per-residue decomposition emphasizes the dominant contribution of van der Waals energy and critical residues are screened. Our study provides the molecular basis of this specific binding and can guide rational AS1411-based aptamers design. Further insights require tight collaborations between the experiments and in silico studies.
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Affiliation(s)
- Lihua Bie
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, China
- Laboratory for Advanced Analytical Technologies, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
| | - Yue Wang
- Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, China
| | - Fuze Jiang
- Laboratory for Advanced Analytical Technologies, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
| | - Zhen Xiao
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Suzhou Institute of Systems Medicine, Suzhou, China
| | - Lianjun Zhang
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- Suzhou Institute of Systems Medicine, Suzhou, China
| | - Jing Wang
- Laboratory for Advanced Analytical Technologies, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
- Institute of Environmental Engineering, ETH Zürich, Zürich, Switzerland
- *Correspondence: Jing Wang,
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33
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Fló M, Carrión F, Olivero-Deibe N, Bianchi S, Portela M, Rammauro F, Alvarez B, Pritsch O. Kinetics of Bovine leukemia virus aspartic protease reveals its dimerization and conformational change. PLoS One 2022; 17:e0271671. [PMID: 35867649 PMCID: PMC9307154 DOI: 10.1371/journal.pone.0271671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Accepted: 07/05/2022] [Indexed: 11/28/2022] Open
Abstract
The retropepsin (PR) of the Bovine leukemia virus (BLV) plays, as in other retroviruses, a crucial role in the transition from the non-infective viral particle to the infective virion by processing the polyprotein Gag. PR is expressed as an immature precursor associated with Gag, after an occasional −1 ribosomal frameshifting event. Self-hydrolysis of PR at specific N- and C-terminal sites releases the monomer that dimerizes giving rise to the active protease. We designed a strategy to express BLV PR in E. coli as a fusion protein with maltose binding protein, with a six-histidine tag at its N-terminal end, and bearing a tobacco etch virus protease hydrolysis site. This allowed us to obtain soluble and mature recombinant PR in relatively good yields, with exactly the same amino acid composition as the native protein. As PR presents relative promiscuity for the hydrolysis sites we designed four fluorogenic peptide substrates based on Förster resonance energy transfer (FRET) in order to characterize the activity of the recombinant enzyme. These substrates opened the way to perform kinetic studies, allowing us to characterize the dimer-monomer equilibrium. Furthermore, we obtained kinetic evidence for the existence of a conformational change that enables the interaction with the substrate. These results constitute a starting point for the elucidation of the kinetic properties of BLV-PR, and may be relevant not only to improve the chemical warfare against this virus but also to better understand other viral PRs.
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Affiliation(s)
- Martín Fló
- Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
- Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
- * E-mail: (OP); (MF)
| | - Federico Carrión
- Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
| | | | - Sergio Bianchi
- Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
- Laboratorio de Biomarcadores Moleculares, Departamento de Fisiopatología, Hospital de Clínicas, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Madelón Portela
- Unidad de Bioquímica y Proteómica Analíticas, Institut Pasteur de Montevideo, Facultad de Ciencias, Montevideo, Uruguay
| | - Florencia Rammauro
- Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
- Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
| | - Beatriz Alvarez
- Laboratorio de Enzimología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Otto Pritsch
- Laboratorio de Inmunovirología, Institut Pasteur de Montevideo, Montevideo, Uruguay
- Departamento de Inmunobiología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
- * E-mail: (OP); (MF)
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34
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A litmus test for classifying recognition mechanisms of transiently binding proteins. Nat Commun 2022; 13:3792. [PMID: 35778416 PMCID: PMC9249894 DOI: 10.1038/s41467-022-31374-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 06/15/2022] [Indexed: 11/17/2022] Open
Abstract
Partner recognition in protein binding is critical for all biological functions, and yet, delineating its mechanism is challenging, especially when recognition happens within microseconds. We present a theoretical and experimental framework based on straight-forward nuclear magnetic resonance relaxation dispersion measurements to investigate protein binding mechanisms on sub-millisecond timescales, which are beyond the reach of standard rapid-mixing experiments. This framework predicts that conformational selection prevails on ubiquitin’s paradigmatic interaction with an SH3 (Src-homology 3) domain. By contrast, the SH3 domain recognizes ubiquitin in a two-state binding process. Subsequent molecular dynamics simulations and Markov state modeling reveal that the ubiquitin conformation selected for binding exhibits a characteristically extended C-terminus. Our framework is robust and expandable for implementation in other binding scenarios with the potential to show that conformational selection might be the design principle of the hubs in protein interaction networks. The authors provide a litmus test for the recognition mechanism of transiently binding proteins based on nuclear magnetic resonance and find a conformational selection binding mechanism through concentration-dependent kinetics of ubiquitin and SH3.
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35
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Bálint M, Zsidó BZ, van der Spoel D, Hetényi C. Binding Networks Identify Targetable Protein Pockets for Mechanism-Based Drug Design. Int J Mol Sci 2022; 23:ijms23137313. [PMID: 35806314 PMCID: PMC9267029 DOI: 10.3390/ijms23137313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 06/22/2022] [Accepted: 06/28/2022] [Indexed: 02/01/2023] Open
Abstract
The human genome codes only a few thousand druggable proteins, mainly receptors and enzymes. While this pool of available drug targets is limited, there is an untapped potential for discovering new drug-binding mechanisms and modes. For example, enzymes with long binding cavities offer numerous prerequisite binding sites that may be visited by an inhibitor during migration from a bulk solution to the destination site. Drug design can use these prerequisite sites as new structural targets. However, identifying these ephemeral sites is challenging. Here, we introduce a new method called NetBinder for the systematic identification and classification of prerequisite binding sites at atomic resolution. NetBinder is based on atomistic simulations of the full inhibitor binding process and provides a networking framework on which to select the most important binding modes and uncover the entire binding mechanism, including previously undiscovered events. NetBinder was validated by a study of the binding mechanism of blebbistatin (a potent inhibitor) to myosin 2 (a promising target for cancer chemotherapy). Myosin 2 is a good test enzyme because, like other potential targets, it has a long internal binding cavity that provides blebbistatin with numerous potential prerequisite binding sites. The mechanism proposed by NetBinder of myosin 2 structural changes during blebbistatin binding shows excellent agreement with experimentally determined binding sites and structural changes. While NetBinder was tested on myosin 2, it may easily be adopted to other proteins with long internal cavities, such as G-protein-coupled receptors or ion channels, the most popular current drug targets. NetBinder provides a new paradigm for drug design by a network-based elucidation of binding mechanisms at an atomic resolution.
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Affiliation(s)
- Mónika Bálint
- Pharmacoinformatics Unit, Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti út 12., 7624 Pécs, Hungary; (M.B.); (B.Z.Z.)
| | - Balázs Zoltán Zsidó
- Pharmacoinformatics Unit, Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti út 12., 7624 Pécs, Hungary; (M.B.); (B.Z.Z.)
| | - David van der Spoel
- Department of Cell and Molecular Biology, Uppsala University, Box 596, SE-75124 Uppsala, Sweden;
| | - Csaba Hetényi
- Pharmacoinformatics Unit, Department of Pharmacology and Pharmacotherapy, Medical School, University of Pécs, Szigeti út 12., 7624 Pécs, Hungary; (M.B.); (B.Z.Z.)
- Correspondence:
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36
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Induced fit with replica exchange improves protein complex structure prediction. PLoS Comput Biol 2022; 18:e1010124. [PMID: 35658008 PMCID: PMC9200320 DOI: 10.1371/journal.pcbi.1010124] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 06/15/2022] [Accepted: 04/20/2022] [Indexed: 11/19/2022] Open
Abstract
Despite the progress in prediction of protein complexes over the last decade, recent blind protein complex structure prediction challenges revealed limited success rates (less than 20% models with DockQ score > 0.4) on targets that exhibit significant conformational change upon binding. To overcome limitations in capturing backbone motions, we developed a new, aggressive sampling method that incorporates temperature replica exchange Monte Carlo (T-REMC) and conformational sampling techniques within docking protocols in Rosetta. Our method, ReplicaDock 2.0, mimics induced-fit mechanism of protein binding to sample backbone motions across putative interface residues on-the-fly, thereby recapitulating binding-partner induced conformational changes. Furthermore, ReplicaDock 2.0 clocks in at 150-500 CPU hours per target (protein-size dependent); a runtime that is significantly faster than Molecular Dynamics based approaches. For a benchmark set of 88 proteins with moderate to high flexibility (unbound-to-bound iRMSD over 1.2 Å), ReplicaDock 2.0 successfully docks 61% of moderately flexible complexes and 35% of highly flexible complexes. Additionally, we demonstrate that by biasing backbone sampling particularly towards residues comprising flexible loops or hinge domains, highly flexible targets can be predicted to under 2 Å accuracy. This indicates that additional gains are possible when mobile protein segments are known.
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Mizukami T, Roder H. Advances in Mixer Design and Detection Methods for Kinetics Studies of Macromolecular Folding and Binding on the Microsecond Time Scale. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27113392. [PMID: 35684328 PMCID: PMC9182321 DOI: 10.3390/molecules27113392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/20/2022] [Accepted: 05/21/2022] [Indexed: 11/16/2022]
Abstract
Many important biological processes such as protein folding and ligand binding are too fast to be fully resolved using conventional stopped-flow techniques. Although advances in mixer design and detection methods have provided access to the microsecond time regime, there is room for improvement in terms of temporal resolution and sensitivity. To address this need, we developed a continuous-flow mixing instrument with a dead time of 12 to 27 µs (depending on solution viscosity) and enhanced sensitivity, sufficient for monitoring tryptophan or tyrosine fluorescence changes at fluorophore concentrations as low as 1 µM. Relying on commercially available laser microfabrication services, we obtained an integrated mixer/flow-cell assembly on a quartz chip, based on a cross-channel configuration with channel dimensions and geometry designed to minimize backpressure. By gradually increasing the width of the observation channel downstream from the mixing region, we are able to monitor a reaction progress time window ranging from ~10 µs out to ~3 ms. By combining a solid-state UV laser with a Galvano-mirror scanning strategy, we achieved highly efficient and uniform fluorescence excitation along the flow channel. Examples of applications, including refolding of acid-denatured cytochrome c triggered by a pH jump and binding of a peptide ligand to a PDZ domain, demonstrate the capability of the technique to resolve fluorescence changes down to the 10 µs time regime on modest amounts of reagents.
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Auton M. New & Notable: ThANNCs for kinetically optimizing ITC. Biophys J 2022; 121:2219-2220. [DOI: 10.1016/j.bpj.2022.05.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Revised: 05/16/2022] [Accepted: 05/20/2022] [Indexed: 11/29/2022] Open
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Cryoelectron microscopy of Na +,K +-ATPase in the two E2P states with and without cardiotonic steroids. Proc Natl Acad Sci U S A 2022; 119:e2123226119. [PMID: 35380894 PMCID: PMC9169807 DOI: 10.1073/pnas.2123226119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The E2P state of Na+,K+-ATPase, in which the ATPase is phosphorylated and of low affinity to Na+ with the extracellular gate opened, shows different biochemical properties depending on whether the phosphate is transferred from ATP in the forward reaction or from inorganic phosphate (Pi) in the backward reaction. We present here cryoelectron microscopy structures of Na+,K+-ATPase in the two E2P states, explaining their different biochemical properties established a half century ago. The new electron microscopy maps show previously unseen structural features, including unexpected binding modes of cardiotonic steroids, specific and medically important inhibitors of the ATPase, and stabilization by ATP of the E2P state. Cryoelectron microscopy (cryo-EM) was applied to Na+,K+-ATPase (NKA) to determine the structures of two E2P states, one (E2PATP) formed by ATP and Mg2+ in the forward reaction, and the other (E2PPi) formed by inorganic phosphate (Pi) and Mg2+ in the backward reaction, with and without ouabain or istaroxime, representatives of classical and new-generation cardiotonic steroids (CTSs). These two E2P states exhibit different biochemical properties. In particular, K+-sensitive acceleration of the dephosphorylation reaction is not observed with E2PPi, attributed to the presence of a Mg2+ ion in the transmembrane cation binding sites. The cryo-EM structures of NKA demonstrate that the two E2P structures are nearly identical but Mg2+ in the transmembrane binding cavity is identified only in E2PPi, corroborating the idea that it should be denoted as E2PPi·Mg2+. We can now explain why the absence of transmembrane Mg2+ in E2PATP confers the K+ sensitivity in dephosphorylation. In addition, we show that ATP bridges the actuator (A) and nucleotide binding (N) domains, stabilizing the E2PATP state; CTS binding causes hardly any changes in the structure of NKA, both in E2PATP and E2PPi·Mg2+, indicating that the binding mechanism is conformational selection; and istaroxime binds to NKA, extending its aminoalkyloxime group deep into the cation binding site. This orientation is upside down compared to that of classical CTSs with respect to the steroid ring. Notably, mobile parts of NKA are resolved substantially better in the electron microscopy (EM) maps than in previous X-ray structures, including sugars sticking out from the β-subunit and many phospholipid molecules.
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Koda SI, Saito S. Multimeric structure enables the acceleration of KaiB-KaiC complex formation induced by ADP/ATP exchange inhibition. PLoS Comput Biol 2022; 18:e1009243. [PMID: 35255087 PMCID: PMC8929707 DOI: 10.1371/journal.pcbi.1009243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 03/17/2022] [Accepted: 02/25/2022] [Indexed: 11/19/2022] Open
Abstract
Circadian clocks tick a rhythm with a nearly 24-hour period in a variety of organisms. In the clock proteins of cyanobacteria, KaiA, KaiB, and KaiC, known as a minimum circadian clock, the slow KaiB-KaiC complex formation is essential in determining the clock period. This complex formation, occurring when the C1 domain of KaiC hexamer binds ADP molecules produced by the ATPase activity of C1, is considered to be promoted by accumulating ADP molecules in C1 through inhibiting the ADP/ATP exchange (ADP release) rather than activating the ATP hydrolysis (ADP production). Significantly, this ADP/ATP exchange inhibition accelerates the complex formation together with its promotion, implying a potential role in the period robustness under environmental perturbations. However, the molecular mechanism of this simultaneous promotion and acceleration remains elusive because inhibition of a backward process generally slows down the whole process. In this article, to investigate the mechanism, we build several reaction models of the complex formation with the pre-binding process concerning the ATPase activity. In these models, six KaiB monomers cooperatively and rapidly bind to C1 when C1 binds ADP molecules more than a given threshold while stabilizing the binding-competent conformation of C1. Through comparison among the models proposed here, we then extract three requirements for the simultaneous promotion and acceleration: the stabilization of the binding-competent C1 by KaiB binding, slow ADP/ATP exchange in the binding-competent C1, and relatively fast ADP/ATP exchange occurring in the binding-incompetent C1 in the presence of KaiB. The last two requirements oblige KaiC to form a multimer. Moreover, as a natural consequence, the present models can also explain why the binding of KaiB to C1 reduces the ATPase activity of C1. Circadian clocks tick a rhythm with a nearly 24-hour period in various organisms. The cyanobacterial circadian clock, composed of only three proteins, KaiA, KaiB, and KaiC, has attracted much attention because of its simplicity. The slow KaiB-KaiC complex formation is essential in determining the clock period in this system. Significantly, this complex formation is accelerated together with its promotion, implying a potential role in the period-keeping mechanism. However, this simultaneous promotion and acceleration is theoretically exceptional because this complex formation is promoted by inhibiting a backward process, which generally slows down the whole process. In this article, we investigate the molecular mechanism of this phenomenon by building mathematical models to find that the binding of KaiB to C1 must lower the ADP/ATP exchange of the C1 domain of KaiC via stabilizing the binding-competent conformation of C1. The present results would be of benefit for future investigations on functional roles of the simultaneous promotion and acceleration in the KaiABC oscillator.
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Affiliation(s)
- Shin-ichi Koda
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Okazaki, Aichi, Japan
- School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
- * E-mail: (SK); (SS)
| | - Shinji Saito
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science, Okazaki, Aichi, Japan
- School of Physical Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Aichi, Japan
- * E-mail: (SK); (SS)
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A linear-polymer-based lactoferrin-selective recognition element for an ELISA mimic: A proof of concept. Anal Chim Acta 2022; 1191:339309. [PMID: 35033252 DOI: 10.1016/j.aca.2021.339309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 11/04/2021] [Accepted: 11/18/2021] [Indexed: 11/20/2022]
Abstract
The synthesis of polymers with tailored properties for the recognition of macromolecules such as proteins is challenging. In this work, the synthesis of a new polymer format, a linear polymer (LP), as the selective recognition element for the globular protein lactoferrin (LF) is proposed as a proof-of-concept study. For the synthesis, a solid-phase strategy using the reversible deactivation radical polymerisation (RDRP) mechanism is proposed. This approach, which is usually used in molecular imprinting, involves the immobilisation of LF on the surface of a solid support, but, unlike classical imprinting, a cross-linker in the polymerisation mixture is not required. Consequently, the copolymer is soluble and flexible, thus overcoming the drawbacks associated with traditional synthetic polymers for macromolecule imprinting. This new polymer format has great potential for replacing natural antibodies in bioassays such as enzyme-linked immunosorbent assays (ELISA), dot blot, western blot, or pull-down. In our case, the linear polymer was used as a recognition element to replace natural antibodies in a LF-selective ELISA. The responses of the linear polymer between LF concentrations of 0.1 nM and 0.25 μM were studied, and a significant difference was observed between the non-specific signals and the signals measured in the presence of the polymeric material. Further, the response versus log concentration curves were fitted to a logistic equation, allowing estimation of the EC50 value: 11.8 ± 1.4 nM. We also confirmed the selective detection of LF using the competitive inhibition of the selective LF-biotin conjugate (LF-Bi) binding to the plastic receptor (LP) for closely related proteins (e.g. those having similar molecular weights or isoelectric points) such as human lysozyme, trypsin, and albumin, which are present in human body fluids. The system presents a cross-reactivity value or selectivity of 1.95% for lysozyme, 0.028% for trypsin, and 0.016% for albumin. The applicability of this method for the determination of urine LF levels in inflammatory and infectious diseases of the human urinary tract is also demonstrated.
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Read BJ, Fisher G, Wissett OLR, Machado TFG, Nicholson J, Mitchell JBO, da Silva RG. Allosteric Inhibition of Acinetobacter baumannii ATP Phosphoribosyltransferase by Protein:Dipeptide and Protein:Protein Interactions. ACS Infect Dis 2022; 8:197-209. [PMID: 34928596 DOI: 10.1021/acsinfecdis.1c00539] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
ATP phosphoribosyltransferase (ATPPRT) catalyzes the first step of histidine biosynthesis in bacteria, namely, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate (PRPP) to generate N1-(5-phospho-β-d-ribosyl)-ATP (PRATP) and pyrophosphate. Catalytic (HisGS) and regulatory (HisZ) subunits assemble in a hetero-octamer where HisZ activates HisGS and mediates allosteric inhibition by histidine. In Acinetobacter baumannnii, HisGS is necessary for the bacterium to persist in the lung during pneumonia. Inhibition of ATPPRT is thus a promising strategy for specific antibiotic development. Here, A. baumannii ATPPRT is shown to follow a rapid equilibrium random kinetic mechanism, unlike any other ATPPRT. Histidine noncompetitively inhibits ATPPRT. Binding kinetics indicates histidine binds to free ATPPRT and to ATPPRT:PRPP and ATPPRT:ATP binary complexes with similar affinity following a two-step binding mechanism, but with distinct kinetic partition of the initial enzyme:inhibitor complex. The dipeptide histidine-proline inhibits ATPPRT competitively and likely uncompetitively, respectively, against PRPP and ATP. Rapid kinetics analysis shows His-Pro binds to the ATPPRT:ATP complex via a two-step binding mechanism. A related HisZ that shares 43% sequence identity with A. baumannii HisZ is a tight-binding allosteric inhibitor of A. baumannii HisGS. These findings lay the foundation for inhibitor design against A. baumannii ATPPRT.
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Affiliation(s)
- Benjamin J. Read
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
| | - Gemma Fisher
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
| | - Oliver L. R. Wissett
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
| | - Teresa F. G. Machado
- School of Chemistry, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
| | - John Nicholson
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
| | - John B. O. Mitchell
- School of Chemistry, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
| | - Rafael G. da Silva
- School of Biology, Biomedical Sciences Research Complex, University of St Andrews, St Andrews, Fife KY16 9ST, United Kingdom
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43
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Guengerich FP. Roles of cytochrome P450 enzymes in pharmacology and toxicology: Past, present, and future. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2022; 95:1-47. [PMID: 35953152 PMCID: PMC9869358 DOI: 10.1016/bs.apha.2021.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The development of the cytochrome P450 (P450) field has been remarkable in the areas of pharmacology and toxicology, particularly in drug development. Today it is possible to use the knowledge base and relatively straightforward assays to make intelligent predictions about drug disposition prior to human dosing. Much is known about the structures, regulation, chemistry of catalysis, and the substrate and inhibitor specificity of human P450s. Many aspects of drug-drug interactions and side effects can be understood in terms of P450s. This knowledge has also been useful in pharmacy practice, as well as in the pharmaceutical industry and medical practice. However, there are still basic and practical questions to address regarding P450s and their roles in pharmacology and toxicology. Another aspect is the discovery of drugs that inhibit P450 to treat diseases.
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Basciu A, Callea L, Motta S, Bonvin AM, Bonati L, Vargiu AV. No dance, no partner! A tale of receptor flexibility in docking and virtual screening. VIRTUAL SCREENING AND DRUG DOCKING 2022. [DOI: 10.1016/bs.armc.2022.08.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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45
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NAKATANI K. Possibilities and challenges of small molecule organic compounds for the treatment of repeat diseases. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2022; 98:30-48. [PMID: 35013029 PMCID: PMC8795530 DOI: 10.2183/pjab.98.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 11/11/2021] [Indexed: 06/14/2023]
Abstract
The instability of repeat sequences in the human genome results in the onset of many neurological diseases if the repeats expand above a certain threshold. The transcripts containing long repeats sequester RNA binding proteins. The mechanism of repeat instability involves metastable slip-out hairpin DNA structures. Synthetic organic chemists have focused on the development of small organic molecules targeting repeat DNA and RNA sequences to treat neurological diseases with repeat-binding molecules. Our laboratory has studied a series of small molecules binding to mismatched base pairs and found molecules capable of binding CAG repeat DNA, which causes Huntington's disease upon expansion, CUG repeat RNA, a typical toxic RNA causing myotonic dystrophy type 1, and UGGAA repeat RNA causing spinocerebellar ataxia type 31. These molecules exhibited significant beneficial effects on disease models in vivo, suggesting the possibilities for small molecules as drugs for treating these neurological diseases.
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Affiliation(s)
- Kazuhiko NAKATANI
- SANKEN, The Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka, Japan
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46
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Pelc LA, Koester SK, Kukla CR, Chen Z, Di Cera E. The active site region plays a critical role in Na + binding to thrombin. J Biol Chem 2022; 298:101458. [PMID: 34861239 PMCID: PMC8695361 DOI: 10.1016/j.jbc.2021.101458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/24/2021] [Accepted: 11/26/2021] [Indexed: 11/23/2022] Open
Abstract
The catalytic activity of thrombin and other enzymes of the blood coagulation and complement cascades is enhanced significantly by binding of Na+ to a site >15 Å away from the catalytic residue S195, buried within the 180 and 220 loops that also contribute to the primary specificity of the enzyme. Rapid kinetics support a binding mechanism of conformational selection where the Na+-binding site is in equilibrium between open (N) and closed (N∗) forms and the cation binds selectively to the N form. Allosteric transduction of this binding step produces enhanced catalytic activity. Molecular details on how Na+ gains access to this site and communicates allosterically with the active site remain poorly defined. In this study, we show that the rate of the N∗→N transition is strongly correlated with the analogous E∗→E transition that governs the interaction of synthetic and physiologic substrates with the active site. This correlation supports the active site as the likely point of entry for Na+ to its binding site. Mutagenesis and structural data rule out an alternative path through the pore defined by the 180 and 220 loops. We suggest that the active site communicates allosterically with the Na+ site through a network of H-bonded water molecules that embeds the primary specificity pocket. Perturbation of the mobility of S195 and its H-bonding capabilities alters interaction with this network and influences the kinetics of Na+ binding and allosteric transduction. These findings have general mechanistic relevance for Na+-activated proteases and allosteric enzymes.
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Affiliation(s)
- Leslie A Pelc
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Sarah K Koester
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Cassandra R Kukla
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Zhiwei Chen
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA
| | - Enrico Di Cera
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri, USA.
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47
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Scher Y, Reuveni S. Gated reactions in discrete time and space. J Chem Phys 2021; 155:234112. [PMID: 34937380 DOI: 10.1063/5.0072393] [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] Open
Abstract
How much time does it take for two molecules to react? If a reaction occurs upon contact, the answer to this question boils down to the classic first-passage time problem: find the time it takes for the two molecules to meet. However, this is not always the case as molecules switch stochastically between reactive and non-reactive states. The reaction is then said to be "gated" by the internal states of the molecules involved, which could have a dramatic influence on kinetics. A unified, continuous-time, approach to gated reactions on networks was presented in a recent paper [Scher and Reuveni, Phys. Rev. Lett. 127, 018301 (2021)]. Here, we build on this recent advancement and develop an analogous discrete-time version of the theory. Similar to continuous-time, we employ a renewal approach to show that the gated reaction time can always be expressed in terms of the corresponding ungated first-passage and return times, which yields formulas for the generating function of the gated reaction-time distribution and its corresponding mean and variance. In cases where the mean reaction time diverges, we show that the long-time asymptotics of the gated problem is inherited from its ungated counterpart. However, when molecules spend most of their time non-reactive, an interim regime of slower power-law decay emerges prior to the terminal asymptotics. The discretization of time also gives rise to resonances and anti-resonances, which were absent from the continuous-time picture. These features are illustrated using two case studies that also demonstrate how the general approach presented herein greatly simplifies the analysis of gated reactions.
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Affiliation(s)
- Yuval Scher
- School of Chemistry, The Center for Physics and Chemistry of Living Systems, The Raymond and Beverly Sackler Center for Computational Molecular and Materials Science, and The Mark Ratner Institute for Single Molecule Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Shlomi Reuveni
- School of Chemistry, The Center for Physics and Chemistry of Living Systems, The Raymond and Beverly Sackler Center for Computational Molecular and Materials Science, and The Mark Ratner Institute for Single Molecule Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
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48
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Redhair M, Atkins WM. Analytical and functional aspects of protein-ligand interactions: Beyond induced fit and conformational selection. Arch Biochem Biophys 2021; 714:109064. [PMID: 34715072 DOI: 10.1016/j.abb.2021.109064] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/18/2021] [Accepted: 10/20/2021] [Indexed: 10/20/2022]
Abstract
Ligand-dependent changes in protein conformation are foundational to biology. Historical mechanistic models for substrate-specific proteins are induced fit (IF) and conformational selection (CS), which invoke a change in protein conformation after ligand binds or before ligand binds, respectively. These mechanisms have important, but rarely discussed, functional relevance because IF vs. CS can differentially affect a protein's substrate specificity or promiscuity, and its regulatory properties. The modern view of proteins as conformational ensembles in both ligand free and bound states, together with the realization that most proteins exhibit some substrate promiscuity, demands a deeper interpretation of the historical models and provides an opportunity to improve mechanistic analyses. Here we describe alternative analytical strategies for distinguishing the historical models, including the more complex expanded versions of IF and CS. Functional implications of the different models are described. We provide an alternative perspective based on protein ensembles interacting with ligand ensembles that clarifies how a single protein can 'apparently' exploit different mechanisms for different ligands. Mechanistic information about protein ensembles can be optimized when they are probed with multiple ligands.
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Affiliation(s)
- Michelle Redhair
- Department of Medicinal Chemistry, Box 375610, University of Washington, Seattle, WA, 98177, USA
| | - William M Atkins
- Department of Medicinal Chemistry, Box 375610, University of Washington, Seattle, WA, 98177, USA.
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49
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Bozovic O, Jankovic B, Hamm P. Using azobenzene photocontrol to set proteins in motion. Nat Rev Chem 2021; 6:112-124. [PMID: 37117294 DOI: 10.1038/s41570-021-00338-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2021] [Indexed: 02/06/2023]
Abstract
Controlling the activity of proteins with azobenzene photoswitches is a potent tool for manipulating their biological function. With the help of light, it is possible to change binding affinities, control allostery or manipulate complex biological processes, for example. Additionally, owing to their intrinsically fast photoisomerization, azobenzene photoswitches can serve as triggers that initiate out-of-equilibrium processes. Such switching of the activity initiates a cascade of conformational events that can be accessed with time-resolved methods. In this Review, we show how the potency of azobenzene photoswitching can be combined with transient spectroscopic techniques to disclose the order of events and experimentally observe biomolecular interactions in real time. This strategy will further our understanding of how a protein can accommodate, adapt and readjust its structure to answer an incoming signal, revealing more of the dynamical character of proteins.
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50
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Pandey S, Calvey G, Katz AM, Malla TN, Koua FHM, Martin-Garcia JM, Poudyal I, Yang JH, Vakili M, Yefanov O, Zielinski KA, Bajt S, Awel S, Doerner K, Frank M, Gelisio L, Jernigan R, Kirkwood H, Kloos M, Koliyadu J, Mariani V, Miller MD, Mills G, Nelson G, Olmos JL, Sadri A, Sato T, Tolstikova A, Xu W, Ourmazd A, Spence JCH, Schwander P, Barty A, Chapman HN, Fromme P, Mancuso AP, Phillips GN, Bean R, Pollack L, Schmidt M. Observation of substrate diffusion and ligand binding in enzyme crystals using high-repetition-rate mix-and-inject serial crystallography. IUCRJ 2021; 8:878-895. [PMID: 34804542 PMCID: PMC8562667 DOI: 10.1107/s2052252521008125] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 08/06/2021] [Indexed: 05/22/2023]
Abstract
Here, we illustrate what happens inside the catalytic cleft of an enzyme when substrate or ligand binds on single-millisecond timescales. The initial phase of the enzymatic cycle is observed with near-atomic resolution using the most advanced X-ray source currently available: the European XFEL (EuXFEL). The high repetition rate of the EuXFEL combined with our mix-and-inject technology enables the initial phase of ceftriaxone binding to the Mycobacterium tuberculosis β-lactamase to be followed using time-resolved crystallography in real time. It is shown how a diffusion coefficient in enzyme crystals can be derived directly from the X-ray data, enabling the determination of ligand and enzyme-ligand concentrations at any position in the crystal volume as a function of time. In addition, the structure of the irreversible inhibitor sulbactam bound to the enzyme at a 66 ms time delay after mixing is described. This demonstrates that the EuXFEL can be used as an important tool for biomedically relevant research.
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Affiliation(s)
- Suraj Pandey
- Physics Department, University of Wisconsin-Milwaukee, 3135 North Maryland Avenue, Milwaukee, WI 53211, USA
| | - George Calvey
- School of Applied and Engineering Physics, Cornell University, 254 Clark Hall, Ithaca, NY 14853, USA
| | - Andrea M. Katz
- School of Applied and Engineering Physics, Cornell University, 254 Clark Hall, Ithaca, NY 14853, USA
| | - Tek Narsingh Malla
- Physics Department, University of Wisconsin-Milwaukee, 3135 North Maryland Avenue, Milwaukee, WI 53211, USA
| | - Faisal H. M. Koua
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Jose M. Martin-Garcia
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287-1604, USA
- Institute of Physical Chemistry Rocasolano, Spanish National Research Council, Calle de Serrano 119, 28006 Madrid, Spain
| | - Ishwor Poudyal
- Physics Department, University of Wisconsin-Milwaukee, 3135 North Maryland Avenue, Milwaukee, WI 53211, USA
| | - Jay-How Yang
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287-1604, USA
| | | | - Oleksandr Yefanov
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Kara A. Zielinski
- School of Applied and Engineering Physics, Cornell University, 254 Clark Hall, Ithaca, NY 14853, USA
| | - Sasa Bajt
- Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Salah Awel
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | | | - Matthias Frank
- Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA 94550, USA
| | - Luca Gelisio
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Rebecca Jernigan
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287-1604, USA
| | | | - Marco Kloos
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Valerio Mariani
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- SLAC National Accelerator Laboratory, 2575 Sand Hill Rd, Menlo Park, California 94025, USA
| | - Mitchell D. Miller
- Department of BioSciences, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Grant Mills
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Garrett Nelson
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Jose L. Olmos
- Department of BioSciences, Rice University, 6100 Main Street, Houston, TX 77005, USA
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA 94158, USA
| | - Alireza Sadri
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Tokushi Sato
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Alexandra Tolstikova
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Weijun Xu
- Department of BioSciences, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Abbas Ourmazd
- Physics Department, University of Wisconsin-Milwaukee, 3135 North Maryland Avenue, Milwaukee, WI 53211, USA
| | - John C. H. Spence
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - Peter Schwander
- Physics Department, University of Wisconsin-Milwaukee, 3135 North Maryland Avenue, Milwaukee, WI 53211, USA
| | - Anton Barty
- Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Henry N. Chapman
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Petra Fromme
- School of Molecular Sciences and Biodesign Center for Applied Structural Discovery, Arizona State University, Tempe, AZ 85287-1604, USA
| | - Adrian P. Mancuso
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Victoria 3086, Australia
| | - George N. Phillips
- Department of BioSciences, Rice University, 6100 Main Street, Houston, TX 77005, USA
- Department of Chemistry, Rice University, 6100 Main Street, Houston, TX 77005, USA
| | - Richard Bean
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, 254 Clark Hall, Ithaca, NY 14853, USA
| | - Marius Schmidt
- Physics Department, University of Wisconsin-Milwaukee, 3135 North Maryland Avenue, Milwaukee, WI 53211, USA
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