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A Long Journey into the Investigation of the Structure–Dynamics–Function Paradigm in Proteins through the Activities of the Palermo Biophysics Group. BIOPHYSICA 2022. [DOI: 10.3390/biophysica2040040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
An overview of the biophysics activity at the Department of Physics and Chemistry Emilio Segrè of the University of Palermo is given. For forty years, the focus of the research has been on the protein structure–dynamics–function paradigm, with the aim of understanding the molecular basis of the relevant mechanisms and the key role of solvent. At least three research lines are identified; the main results obtained in collaboration with other groups in Italy and abroad are presented. This review is dedicated to the memory of Professors Massimo Ugo Palma, Maria Beatrice Palma Vittorelli, and Lorenzo Cordone, which were the founders of the Palermo School of Biophysics. We all have been, directly or indirectly, their pupils; we miss their enthusiasm for scientific research, their deep physical insights, their suggestions, their strict but always constructive criticisms, and, most of all, their friendship. This paper is dedicated also to the memory of Prof. Hans Frauenfelder, whose pioneering works on nonexponential rebinding kinetics, protein substates, and energy landscape have inspired a large part of our work in the field of protein dynamics.
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2
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Oligomerization processes limit photoactivation and recovery of the Orange Carotenoid Protein. Biophys J 2022; 121:2849-2872. [PMID: 35794830 PMCID: PMC9388578 DOI: 10.1016/j.bpj.2022.07.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 05/17/2022] [Accepted: 07/01/2022] [Indexed: 11/23/2022] Open
Abstract
The Orange Carotenoid Protein (OCP) is a photoactive protein involved in cyanobacterial photoprotection, by quenching of the excess of light harvested energy. The photoactivation mechanism remains elusive, in part due to absence of data pertaining to the timescales over which protein structural changes take place. It also remains unclear whether or not oligomerization of the dark-adapted and light-adapted OCP could play a role in the regulation of its energy quenching activity. Here, we probed photo-induced structural changes in OCP by a combination of static and time-resolved X-ray scattering and steady-state and transient optical spectroscopy in the visible range. Our results suggest that oligomerization partakes in regulation of the OCP photocycle, with different oligomers slowing down the overall thermal recovery of the dark-adapted state of OCP. They furthermore reveal that upon non-photoproductive excitation, a numbed-state forms, which remains in a non-photoexcitable structural state for at least ∼0.5 μs after absorption of a first photon.
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3
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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: 20] [Impact Index Per Article: 6.7] [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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4
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More than a Confinement: “Soft” and “Hard” Enzyme Entrapment Modulates Biological Catalyst Function. Catalysts 2019. [DOI: 10.3390/catal9121024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Catalysis makes chemical and biochemical reactions kinetically accessible. From a technological point of view, organic, inorganic, and biochemical catalysis is relevant for several applications, from industrial synthesis to biomedical, material, and food sciences. A heterogeneous catalyst, i.e., a catalyst confined in a different phase with respect to the reagents’ phase, requires either its physical confinement in an immobilization matrix or its physical adsorption on a surface. In this review, we will focus on the immobilization of biological catalysts, i.e., enzymes, by comparing hard and soft immobilization matrices and their effect on the modulation of the catalysts’ function. Indeed, unlike smaller molecules, the catalytic activity of protein catalysts depends on their structure, conformation, local environment, and dynamics, properties that can be strongly affected by the immobilization matrices, which, therefore, not only provide physical confinement, but also modulate catalysis.
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Yang C, Choi M, Kim JG, Kim H, Muniyappan S, Nozawa S, Adachi SI, Henning R, Kosheleva I, Ihee H. Protein Structural Dynamics of Wild-Type and Mutant Homodimeric Hemoglobin Studied by Time-Resolved X-Ray Solution Scattering. Int J Mol Sci 2018; 19:ijms19113633. [PMID: 30453670 PMCID: PMC6274816 DOI: 10.3390/ijms19113633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 11/09/2018] [Accepted: 11/14/2018] [Indexed: 01/30/2023] Open
Abstract
The quaternary transition between the relaxed (R) and tense (T) states of heme-binding proteins is a textbook example for the allosteric structural transition. Homodimeric hemoglobin (HbI) from Scapharca inaequivalvis is a useful model system for investigating the allosteric behavior because of the relatively simple quaternary structure. To understand the cooperative transition of HbI, wild-type and mutants of HbI have been studied by using time-resolved X-ray solution scattering (TRXSS), which is sensitive to the conformational changes. Herein, we review the structural dynamics of HbI investigated by TRXSS and compare the results of TRXSS with those of other techniques.
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Affiliation(s)
- Cheolhee Yang
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
- Center for Nanomaterials and Chemical Reactions, Institute of Basic Science (IBS), Daejeon 34141, Korea.
| | - Minseo Choi
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
- Center for Nanomaterials and Chemical Reactions, Institute of Basic Science (IBS), Daejeon 34141, Korea.
| | - Jong Goo Kim
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
- Center for Nanomaterials and Chemical Reactions, Institute of Basic Science (IBS), Daejeon 34141, Korea.
| | - Hanui Kim
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
- Center for Nanomaterials and Chemical Reactions, Institute of Basic Science (IBS), Daejeon 34141, Korea.
| | - Srinivasan Muniyappan
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
- Center for Nanomaterials and Chemical Reactions, Institute of Basic Science (IBS), Daejeon 34141, Korea.
| | - Shunsuke Nozawa
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
| | - Shin-Ichi Adachi
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
- Department of Materials Structure Science, School of High Energy Accelerator Science, The Graduate University for Advanced Studies, 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan.
| | - Robert Henning
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL 60637, USA.
| | - Irina Kosheleva
- Center for Advanced Radiation Sources, The University of Chicago, Chicago, IL 60637, USA.
| | - Hyotcherl Ihee
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Korea.
- Center for Nanomaterials and Chemical Reactions, Institute of Basic Science (IBS), Daejeon 34141, Korea.
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6
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Cho HS, Schotte F, Stadnytskyi V, DiChiara A, Henning R, Anfinrud P. Dynamics of Quaternary Structure Transitions in R-State Carbonmonoxyhemoglobin Unveiled in Time-Resolved X-ray Scattering Patterns Following a Temperature Jump. J Phys Chem B 2018; 122:11488-11496. [PMID: 30285440 DOI: 10.1021/acs.jpcb.8b07414] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It is well-known that tetrameric hemoglobin binds ligands cooperatively by undergoing a ligand-induced T → R quaternary structure transition, a structure-function relationship that has long served as a model system for understanding allostery in proteins. However, kinetic studies of the reverse, R → T quaternary structure transition following photolysis of carbonmonoxyhemoglobin (HbCO) reveal complex behavior that may be better explained by the presence of two different R quaternary structures coexisting in thermal equilibrium. Indeed, we report here time-resolved small- and wide-angle X-ray scattering (SAXS/WAXS) patterns of HbCO following a temperature jump that not only provide unambiguous evidence for more than one R state, but also unveil the time scale for interconversion between them. Since the time scale for the photolysis-induced R → T transition is likely different for different R-states, this structural heterogeneity must be accounted for to properly explain the kinetic heterogeneity observed in time-resolved spectroscopic studies following photolysis of HbCO.
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Affiliation(s)
- Hyun Sun Cho
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases , National Institutes of Health , Bethesda , Maryland 220892-0520 , United States
| | - Friedrich Schotte
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases , National Institutes of Health , Bethesda , Maryland 220892-0520 , United States
| | - Valentyn Stadnytskyi
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases , National Institutes of Health , Bethesda , Maryland 220892-0520 , United States
| | - Anthony DiChiara
- Argonne National Laboratory , 9700 S. Cass Ave. , Argonne , Illinois 60439 , United States
| | - Robert Henning
- Center for Advanced Radiation Sources , University of Chicago , Chicago , Illinois 60637 , United States
| | - Philip Anfinrud
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases , National Institutes of Health , Bethesda , Maryland 220892-0520 , United States
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7
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Chang S, Mizuno M, Ishikawa H, Mizutani Y. Tertiary dynamics of human adult hemoglobin fixed in R and T quaternary structures. Phys Chem Chem Phys 2018; 20:3363-3372. [PMID: 29260810 DOI: 10.1039/c7cp06287g] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Protein dynamics of human adult hemoglobin and its mutants restricted in R and T quaternary states following ligand photolysis were studied by time-resolved resonance Raman spectroscopy. In the time-resolved spectra, we observed spectral changes of in-plane stretching modes of heme and the iron-histidine stretching mode of the Fe-His bond for all the hemoglobin samples. The βD99N mutant, which adopts the R state in both the ligand-bound and the deoxy forms, showed similar temporal behaviors in time-resolved resonance Raman spectra as wild-type recombinant hemoglobin until 10 μs, consistent with the fact that the mutant undergoes only the tertiary structural changes in the R state. The βN102T mutant, which adopts the T state in both the ligand-bound and the deoxy forms, showed much slower tertiary structural changes, suggesting that the EF helical motion is decelerated by the change of the intersubunit interactions. The present data indicate that the allosteric kinetic response between the interhelical hydrogen bonds of the EF helices and the intersubunit hydrogen bonds is bidirectional. The implications of these results for understanding the allosteric pathway of Hb are discussed in detail.
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Affiliation(s)
- Shanyan Chang
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
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Mizutani Y. Time-Resolved Resonance Raman Spectroscopy and Application to Studies on Ultrafast Protein Dynamics. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2017. [DOI: 10.1246/bcsj.20170218] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yasuhisa Mizutani
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043
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9
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Gell DA. Structure and function of haemoglobins. Blood Cells Mol Dis 2017; 70:13-42. [PMID: 29126700 DOI: 10.1016/j.bcmd.2017.10.006] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Revised: 10/29/2017] [Accepted: 10/30/2017] [Indexed: 12/18/2022]
Abstract
Haemoglobin (Hb) is widely known as the iron-containing protein in blood that is essential for O2 transport in mammals. Less widely recognised is that erythrocyte Hb belongs to a large family of Hb proteins with members distributed across all three domains of life-bacteria, archaea and eukaryotes. This review, aimed chiefly at researchers new to the field, attempts a broad overview of the diversity, and common features, in Hb structure and function. Topics include structural and functional classification of Hbs; principles of O2 binding affinity and selectivity between O2/NO/CO and other small ligands; hexacoordinate (containing bis-imidazole coordinated haem) Hbs; bacterial truncated Hbs; flavohaemoglobins; enzymatic reactions of Hbs with bioactive gases, particularly NO, and protection from nitrosative stress; and, sensor Hbs. A final section sketches the evolution of work on the structural basis for allosteric O2 binding by mammalian RBC Hb, including the development of newer kinetic models. Where possible, reference to historical works is included, in order to provide context for current advances in Hb research.
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Affiliation(s)
- David A Gell
- School of Medicine, University of Tasmania, TAS 7000, Australia.
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Chen WR, Yu Y, Zulfajri M, Lin PC, Wang CC. Phthalide Derivatives from Angelica Sinensis Decrease Hemoglobin Oxygen Affinity: A New Allosteric-Modulating Mechanism and Potential Use as 2,3-BPG Functional Substitutes. Sci Rep 2017; 7:5504. [PMID: 28710372 PMCID: PMC5511246 DOI: 10.1038/s41598-017-04554-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Accepted: 05/16/2017] [Indexed: 11/09/2022] Open
Abstract
Angelica sinensis (AS), one of the most versatile herbal medicines remains widely used due to its multi-faceted pharmacologic activities. Besides its traditional use as the blood-nourishing tonic, its anti-hypertensive, anti-cardiovascular, neuroprotective and anti-cancer effects have been reported. Albeit the significant therapeutic effects, how AS exerts such diverse efficacies from the molecular level remains elusive. Here we investigate the influences of AS and four representative phthalide derivatives from AS on the structure and function of hemoglobin (Hb). From the spectroscopy and oxygen equilibrium experiments, we show that AS and the chosen phthalides inhibited the oxygenated Hb from transforming into the high-affinity “relaxed” (R) state, decreasing Hb’s oxygen affinity. It reveals that phthalides cooperate with the endogenous Hb modulator, 2,3-bisphosphoglycerate (2,3-BPG) to synergetically regulate Hb allostery. From the docking modeling, phthalides appear to interact with Hb mainly through its α1/α2 interface, likely strengthening four (out of six) Hb “tense” (T) state stabilizing salt-bridges. A new allosteric-modulating mechanism is proposed to rationalize the capacity of phthalides to facilitate Hb oxygen transport, which may be inherently correlated with the therapeutic activities of AS. The potential of phthalides to serve as 2,3-BPG substitutes/supplements and their implications in the systemic biology and preventive medicine are discussed.
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Affiliation(s)
- Wei-Ren Chen
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, 80424, Republic of China
| | - Youqing Yu
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, 80424, Republic of China
| | - Muhammad Zulfajri
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, 80424, Republic of China
| | - Ping-Cheng Lin
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, 80424, Republic of China
| | - Chia C Wang
- Department of Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan, 80424, Republic of China. .,Aerosol Science Research Center, National Sun Yat-sen University, Kaohsiung, Taiwan, 80424, Republic of China.
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11
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Lal J, Maccarini M, Fouquet P, Ho NT, Ho C, Makowski L. Modulation of hemoglobin dynamics by an allosteric effector. Protein Sci 2017; 26:505-514. [PMID: 27977887 PMCID: PMC5326564 DOI: 10.1002/pro.3099] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 12/03/2016] [Accepted: 12/07/2016] [Indexed: 11/24/2022]
Abstract
Hemoglobin (Hb) is an extensively studied paradigm of proteins that alter their function in response to allosteric effectors. Models of its action have been used as prototypes for structure‐function relationships in many proteins, and models for the molecular basis of its function have been deeply studied and extensively argued. Recent reports suggest that dynamics may play an important role in its function. Relatively little is known about the slow, correlated motions of hemoglobin subunits in various structural states because experimental and computational strategies for their characterization are challenging. Allosteric effectors such as inositol hexaphosphate (IHP) bind to both deoxy‐Hb and HbCO, albeit at different sites, leading to a lowered oxygen affinity. The manner in which these effectors impact oxygen binding is unclear and may involve changes in structure, dynamics or both. Here we use neutron spin echo measurements accompanied by wide‐angle X‐ray scattering to show that binding of IHP to HbCO results in an increase in the rate of coordinated motions of Hb subunits relative to one another with little if any change in large scale structure. This increase of large‐scale dynamics seems to be coupled with a decrease in the average magnitude of higher frequency modes of individual residues. These observations indicate that enhanced dynamic motions contribute to the functional changes induced by IHP and suggest that they may be responsible for the lowered oxygen affinity triggered by these effectors.
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Affiliation(s)
- Jyotsana Lal
- Biosciences Division, Argonne National Laboratory, Argonne, Illinois, 60439
| | - Marco Maccarini
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - Peter Fouquet
- Institut Laue-Langevin, CS 20156, 38042 Grenoble Cedex 9, France
| | - Nancy T Ho
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213
| | - Chien Ho
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213
| | - Lee Makowski
- Biosciences Division, Argonne National Laboratory, Argonne, Illinois, 60439.,Department of Bioengineering, Northeastern University, Boston, Massachusetts, 02115
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12
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Ghazal A, Lafleur JP, Mortensen K, Kutter JP, Arleth L, Jensen GV. Recent advances in X-ray compatible microfluidics for applications in soft materials and life sciences. LAB ON A CHIP 2016; 16:4263-4295. [PMID: 27731448 DOI: 10.1039/c6lc00888g] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The increasingly narrow and brilliant beams at X-ray facilities reduce the requirements for both sample volume and data acquisition time. This creates new possibilities for the types and number of sample conditions that can be examined but simultaneously increases the demands in terms of sample preparation. Microfluidic-based sample preparation techniques have emerged as elegant alternatives that can be integrated directly into the experimental X-ray setup remedying several shortcomings of more traditional methods. We review the use of microfluidic devices in conjunction with X-ray measurements at synchrotron facilities in the context of 1) mapping large parameter spaces, 2) performing time resolved studies of mixing-induced kinetics, and 3) manipulating/processing samples in ways which are more demanding or not accessible on the macroscale. The review covers the past 15 years and focuses on applications where synchrotron data collection is performed in situ, i.e. directly on the microfluidic platform or on a sample jet from the microfluidic device. Considerations such as the choice of materials and microfluidic designs are addressed. The combination of microfluidic devices and measurements at large scale X-ray facilities is still emerging and far from mature, but it definitely offers an exciting array of new possibilities.
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Affiliation(s)
- Aghiad Ghazal
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark.
| | - Josiane P Lafleur
- Dept. of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Kell Mortensen
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark.
| | - Jörg P Kutter
- Dept. of Pharmacy, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen, Denmark
| | - Lise Arleth
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark.
| | - Grethe V Jensen
- Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark.
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13
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Esquerra RM, Bibi BM, Tipgunlakant P, Birukou I, Soman J, Olson JS, Kliger DS, Goldbeck RA. Role of Heme Pocket Water in Allosteric Regulation of Ligand Reactivity in Human Hemoglobin. Biochemistry 2016; 55:4005-17. [PMID: 27355904 PMCID: PMC4978812 DOI: 10.1021/acs.biochem.6b00081] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Water molecules can enter the heme pockets of unliganded myoglobins and hemoglobins, hydrogen bond with the distal histidine, and introduce steric barriers to ligand binding. The spectrokinetics of photodissociated CO complexes of human hemoglobin and its isolated α and β chains were analyzed for the effect of heme hydration on ligand rebinding. A strong coupling was observed between heme hydration and quaternary state. This coupling may contribute significantly to the 20-60-fold difference between the R- and T-state bimolecular CO binding rate constants and thus to the modulation of ligand reactivity that is the hallmark of hemoglobin allostery. Heme hydration proceeded over the course of several kinetic phases in the tetramer, including the R to T quaternary transition. An initial 150 ns hydration phase increased the R-state distal pocket water occupancy, nw(R), to a level similar to that of the isolated α (∼60%) and β (∼10%) chains, resulting in a modest barrier to ligand binding. A subsequent phase, concurrent with the first step of the R → T transition, further increased the level of heme hydration, increasing the barrier. The final phase, concurrent with the final step of the allosteric transition, brought the water occupancy of the T-state tetramer, nw(T), even higher and close to full occupancy in both the α and β subunits (∼90%). This hydration level could present an even larger barrier to ligand binding and contribute significantly to the lower iron reactivity of the T state toward CO.
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Affiliation(s)
- Raymond M. Esquerra
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132, United States
| | - Bushra M. Bibi
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132, United States
| | - Pooncharas Tipgunlakant
- Department of Chemistry and Biochemistry, San Francisco State University, San Francisco, California 94132, United States
| | - Ivan Birukou
- Department of Biochemistry and Cell Biology and W. M. Keck Center for Computational Biology, Rice University, Houston, Texas 77005, United States
| | - Jayashree Soman
- Department of Biochemistry and Cell Biology and W. M. Keck Center for Computational Biology, Rice University, Houston, Texas 77005, United States
| | - John S. Olson
- Department of Biochemistry and Cell Biology and W. M. Keck Center for Computational Biology, Rice University, Houston, Texas 77005, United States
| | - David S. Kliger
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
| | - Robert A. Goldbeck
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064, United States
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14
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Ramírez CL, Petruk A, Bringas M, Estrin DA, Roitberg AE, Marti MA, Capece L. Coarse-Grained Simulations of Heme Proteins: Validation and Study of Large Conformational Transitions. J Chem Theory Comput 2016; 12:3390-7. [DOI: 10.1021/acs.jctc.6b00278] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Claudia L. Ramírez
- Dto.
de Química Inorgánica, Analítica y Química
Física, Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/INQUIMAE-CONICET, Buenos Aires, C1428EGA, Argentina
- Dto.
de Química Biologica Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/IQUIBICEN-CONICET, Buenos Aires, C1428EGA, Argentina
| | - Ariel Petruk
- Dto.
de Química Inorgánica, Analítica y Química
Física, Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/INQUIMAE-CONICET, Buenos Aires, C1428EGA, Argentina
| | - Mauro Bringas
- Dto.
de Química Inorgánica, Analítica y Química
Física, Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/INQUIMAE-CONICET, Buenos Aires, C1428EGA, Argentina
| | - Dario A. Estrin
- Dto.
de Química Inorgánica, Analítica y Química
Física, Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/INQUIMAE-CONICET, Buenos Aires, C1428EGA, Argentina
| | - Adrian E. Roitberg
- Department
of Chemistry, University of Florida, Gainesville, Florida 32611-7200, United States
| | - Marcelo A. Marti
- Dto.
de Química Biologica Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/IQUIBICEN-CONICET, Buenos Aires, C1428EGA, Argentina
| | - Luciana Capece
- Dto.
de Química Inorgánica, Analítica y Química
Física, Fac. de Ciencias Exactas y Naturales, Univ. de Buenos Aires/INQUIMAE-CONICET, Buenos Aires, C1428EGA, Argentina
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15
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16
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Khadeeva L, Kaszub W, Lorenc M, Malfant I, Buron-Le Cointe M. Two-Step Photon Absorption Driving the Chemical Reaction in the Model Ruthenium Nitrosyl System [Ru(py)4Cl(NO)](PF6)2·1/2H2O. Inorg Chem 2016; 55:4117-23. [DOI: 10.1021/acs.inorgchem.5b02572] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Liya Khadeeva
- Institut de Physique
de Rennes, UMR UR1-CNRS 6251, Université Rennes 1, avenue du général
Leclerc, Rennes 35042 Cedex, France
| | - Wawrzyniec Kaszub
- Institut de Physique
de Rennes, UMR UR1-CNRS 6251, Université Rennes 1, avenue du général
Leclerc, Rennes 35042 Cedex, France
| | - Maciej Lorenc
- Institut de Physique
de Rennes, UMR UR1-CNRS 6251, Université Rennes 1, avenue du général
Leclerc, Rennes 35042 Cedex, France
| | - Isabelle Malfant
- Laboratoire de Chimie de Coordination, CNRS UPR 8241, 205 route
de Narbonne, Toulouse 31077
Cedex, France
| | - Marylise Buron-Le Cointe
- Institut de Physique
de Rennes, UMR UR1-CNRS 6251, Université Rennes 1, avenue du général
Leclerc, Rennes 35042 Cedex, France
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17
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Kim JG, Muniyappan S, Oang KY, Kim TW, Yang C, Kim KH, Kim J, Ihee H. Cooperative protein structural dynamics of homodimeric hemoglobin linked to water cluster at subunit interface revealed by time-resolved X-ray solution scattering. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2016; 3:023610. [PMID: 27158635 PMCID: PMC4833754 DOI: 10.1063/1.4947071] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 04/06/2016] [Indexed: 05/30/2023]
Abstract
Homodimeric hemoglobin (HbI) consisting of two subunits is a good model system for investigating the allosteric structural transition as it exhibits cooperativity in ligand binding. In this work, as an effort to extend our previous study on wild-type and F97Y mutant HbI, we investigate structural dynamics of a mutant HbI in solution to examine the role of well-organized interfacial water cluster, which has been known to mediate intersubunit communication in HbI. In the T72V mutant of HbI, the interfacial water cluster in the T state is perturbed due to the lack of Thr72, resulting in two less interfacial water molecules than in wild-type HbI. By performing picosecond time-resolved X-ray solution scattering experiment and kinetic analysis on the T72V mutant, we identify three structurally distinct intermediates (I1, I2, and I3) and show that the kinetics of the T72V mutant are well described by the same kinetic model used for wild-type and F97Y HbI, which involves biphasic kinetics, geminate recombination, and bimolecular CO recombination. The optimized kinetic model shows that the R-T transition and bimolecular CO recombination are faster in the T72V mutant than in the wild type. From structural analysis using species-associated difference scattering curves for the intermediates, we find that the T-like deoxy I3 intermediate in solution has a different structure from deoxy HbI in crystal. In addition, we extract detailed structural parameters of the intermediates such as E-F distance, intersubunit rotation angle, and heme-heme distance. By comparing the structures of protein intermediates in wild-type HbI and the T72V mutant, we reveal how the perturbation in the interfacial water cluster affects the kinetics and structures of reaction intermediates of HbI.
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Affiliation(s)
| | | | | | | | | | | | - Jeongho Kim
- Department of Chemistry, Inha University , Incheon 402-751, South Korea
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18
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Yang C, Choi J, Ihee H. The time scale of the quaternary structural changes in hemoglobin revealed using the transient grating technique. Phys Chem Chem Phys 2015; 17:22571-5. [PMID: 26272458 DOI: 10.1039/c5cp03059e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The quaternary structural transition between the R and T states of human hemoglobin was investigated using the transient grating technique. The results presented herein reveal that the quaternary structural change accompanied by the R-T transition occurs within a few microseconds.
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Affiliation(s)
- Cheolhee Yang
- Department of Chemistry, KAIST, Daejeon 305-701, Republic of Korea.
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19
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Brinkmann LUL, Hub JS. Anisotropic time-resolved solution X-ray scattering patterns from explicit-solvent molecular dynamics. J Chem Phys 2015; 143:104108. [DOI: 10.1063/1.4930013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Levin U. L. Brinkmann
- Institute for Microbiology and Genetics, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | - Jochen S. Hub
- Institute for Microbiology and Genetics, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
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20
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Levantino M, Yorke BA, Monteiro DC, Cammarata M, Pearson AR. Using synchrotrons and XFELs for time-resolved X-ray crystallography and solution scattering experiments on biomolecules. Curr Opin Struct Biol 2015; 35:41-8. [PMID: 26342489 DOI: 10.1016/j.sbi.2015.07.017] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 07/27/2015] [Accepted: 07/31/2015] [Indexed: 11/17/2022]
Abstract
Time-resolved structural information is key to understand the mechanism of biological processes, such as catalysis and signalling. Recent developments in X-ray sources as well as data collection and analysis methods are making routine time-resolved X-ray crystallography and solution scattering experiments a real possibility for structural biologists. Here we review the information that can be obtained from these techniques and discuss the considerations that must be taken into account when designing a time-resolved experiment.
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Affiliation(s)
- Matteo Levantino
- Department of Physics and Chemistry, University of Palermo, Palermo 90128, Italy
| | - Briony A Yorke
- Hamburg Centre for Ultrafast Imaging & Institute of Nanostructure and Solid State Physics, University of Hamburg, Hamburg 22607, Germany
| | - Diana Cf Monteiro
- Astbury Centre for Structural Molecular Biology & School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
| | - Marco Cammarata
- Department of Physics, UMR UR1-CNRS 6251, University of Rennes 1, Rennes 35042, France
| | - Arwen R Pearson
- Hamburg Centre for Ultrafast Imaging & Institute of Nanostructure and Solid State Physics, University of Hamburg, Hamburg 22607, Germany.
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21
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Motion of proximal histidine and structural allosteric transition in soluble guanylate cyclase. Proc Natl Acad Sci U S A 2015; 112:E1697-704. [PMID: 25831539 DOI: 10.1073/pnas.1423098112] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
We investigated the changes of heme coordination in purified soluble guanylate cyclase (sGC) by time-resolved spectroscopy in a time range encompassing 11 orders of magnitude (from 1 ps to 0.2 s). After dissociation, NO either recombines geminately to the 4-coordinate (4c) heme (τG1 = 7.5 ps; 97 ± 1% of the population) or exits the heme pocket (3 ± 1%). The proximal His rebinds to the 4c heme with a 70-ps time constant. Then, NO is distributed in two approximately equal populations (1.5%). One geminately rebinds to the 5c heme (τG2 = 6.5 ns), whereas the other diffuses out to the solution, from where it rebinds bimolecularly (τ = 50 μs with [NO] = 200 μM) forming a 6c heme with a diffusion-limited rate constant of 2 × 10(8) M(-1)⋅s(-1). In both cases, the rebinding of NO induces the cleavage of the Fe-His bond that can be observed as an individual reaction step. Saliently, the time constant of bond cleavage differs depending on whether NO binds geminately or from solution (τ5C1 = 0.66 μs and τ5C2 = 10 ms, respectively). Because the same event occurs with rates separated by four orders of magnitude, this measurement implies that sGC is in different structural states in both cases, having different strain exerted on the Fe-His bond. We show here that this structural allosteric transition takes place in the range 1-50 μs. In this context, the detection of NO binding to the proximal side of sGC heme is discussed.
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22
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Affiliation(s)
- Yue Yuan
- Department of Biological Sciences Carnegie Mellon University Pittsburgh, PA 15213
| | - Ming F. Tam
- Department of Biological Sciences Carnegie Mellon University Pittsburgh, PA 15213
| | - Virgil Simplaceanu
- Department of Biological Sciences Carnegie Mellon University Pittsburgh, PA 15213
| | - Chien Ho
- Department of Biological Sciences Carnegie Mellon University Pittsburgh, PA 15213
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23
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Jones EM, Monza E, Balakrishnan G, Blouin GC, Mak PJ, Zhu Q, Kincaid JR, Guallar V, Spiro TG. Differential control of heme reactivity in alpha and beta subunits of hemoglobin: a combined Raman spectroscopic and computational study. J Am Chem Soc 2014; 136:10325-39. [PMID: 24991732 PMCID: PMC4353013 DOI: 10.1021/ja503328a] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Indexed: 12/05/2022]
Abstract
The use of hybrid hemoglobin (Hb), with mesoheme substituted for protoheme, allows separate monitoring of the α or β hemes along the allosteric pathway. Using resonance Raman (rR) spectroscopy in silica gel, which greatly slows protein motions, we have observed that the Fe-histidine stretching frequency, νFeHis, which is a monitor of heme reactivity, evolves between frequencies characteristic of the R and T states, for both α or β chains, prior to the quaternary R-T and T-R shifts. Computation of νFeHis, using QM/MM and the conformational search program PELE, produced remarkable agreement with experiment. Analysis of the PELE structures showed that the νFeHis shifts resulted from heme distortion and, in the α chain, Fe-His bond tilting. These results support the tertiary two-state model of ligand binding (Henry et al., Biophys. Chem. 2002, 98, 149). Experimentally, the νFeHis evolution is faster for β than for α chains, and pump-probe rR spectroscopy in solution reveals an inflection in the νFeHis time course at 3 μs for β but not for α hemes, an interval previously shown to be the first step in the R-T transition. In the α chain νFeHis dropped sharply at 20 μs, the final step in the R-T transition. The time courses are fully consistent with recent computational mapping of the R-T transition via conjugate peak refinement by Karplus and co-workers (Fischer et al., Proc. Natl. Acad. Sci. U. S. A. 2011, 108, 5608). The effector molecule IHP was found to lower νFeHis selectively for α chains within the R state, and a binding site in the α1α2 cleft is suggested.
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Affiliation(s)
- Eric M. Jones
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States
| | - Emanuele Monza
- Joint
BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, c/Jordi Girona 29, 08034 Barcelona, Spain
| | - Gurusamy Balakrishnan
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States
| | - George C. Blouin
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States
| | - Piotr J. Mak
- Department
of Chemistry, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - Qianhong Zhu
- Department
of Chemistry, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - James R. Kincaid
- Department
of Chemistry, Marquette University, Milwaukee, Wisconsin 53233, United States
| | - Victor Guallar
- Joint
BSC-IRB Research Program in Computational Biology, Barcelona Supercomputing Center, c/Jordi Girona 29, 08034 Barcelona, Spain
- Institució
Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010 Barcelona, Spain
| | - Thomas G. Spiro
- Department
of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, United States
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24
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Takayanagi M, Kurisaki I, Nagaoka M. Non-site-specific allosteric effect of oxygen on human hemoglobin under high oxygen partial pressure. Sci Rep 2014; 4:4601. [PMID: 24710521 PMCID: PMC3978498 DOI: 10.1038/srep04601] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 03/12/2014] [Indexed: 12/11/2022] Open
Abstract
Protein allostery is essential for vital activities. Allosteric regulation of human hemoglobin (HbA) with two quaternary states T and R has been a paradigm of allosteric structural regulation of proteins. It is widely accepted that oxygen molecules (O2) act as a “site-specific” homotropic effector, or the successive O2 binding to the heme brings about the quaternary regulation. However, here we show that the site-specific allosteric effect is not necessarily only a unique mechanism of O2 allostery. Our simulation results revealed that the solution environment of high O2 partial pressure enhances the quaternary change from T to R without binding to the heme, suggesting an additional “non-site-specific” allosteric effect of O2. The latter effect should play a complementary role in the quaternary change by affecting the intersubunit contacts. This analysis must become a milestone in comprehensive understanding of the allosteric regulation of HbA from the molecular point of view.
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Affiliation(s)
- Masayoshi Takayanagi
- 1] Venture Business Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan [2] Graduate School of Information Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan [3] Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Honmachi, Kawaguchi 332-0012, Japan
| | - Ikuo Kurisaki
- Graduate School of Information Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Masataka Nagaoka
- 1] Graduate School of Information Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan [2] Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Honmachi, Kawaguchi 332-0012, Japan
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25
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Hwan Kim K, Kim J, Hyuk Lee J, Ihee H. Topical Review: Molecular reaction and solvation visualized by time-resolved X-ray solution scattering: Structure, dynamics, and their solvent dependence. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2014; 1:011301. [PMID: 26798770 PMCID: PMC4711596 DOI: 10.1063/1.4865234] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 01/17/2014] [Indexed: 05/16/2023]
Abstract
Time-resolved X-ray solution scattering is sensitive to global molecular structure and can track the dynamics of chemical reactions. In this article, we review our recent studies on triiodide ion (I3 (-)) and molecular iodine (I2) in solution. For I3 (-), we elucidated the excitation wavelength-dependent photochemistry and the solvent-dependent ground-state structure. For I2, by combining time-slicing scheme and deconvolution data analysis, we mapped out the progression of geminate recombination and the associated structural change in the solvent cage. With the aid of X-ray free electron lasers, even clearer observation of ultrafast chemical events will be made possible in the near future.
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Affiliation(s)
| | - Jeongho Kim
- Department of Chemistry, Inha University , Incheon 402-751, South Korea
| | - Jae Hyuk Lee
- Department of Chemistry, KAIST , Daejeon 305-701, South Korea
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26
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Mandal SS, Cristiglio V, Lindner P, Bhattacharyya AJ. Small-angle neutron scattering studies of hemoglobin confined inside silica tubes of varying sizes. Chemphyschem 2013; 15:302-9. [PMID: 24339406 DOI: 10.1002/cphc.201300863] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 11/14/2013] [Indexed: 11/08/2022]
Abstract
In addition to the chemical nature of the surface, the dimensions of the confining host exert a significant influence on confined protein structures; this results in immense biological implications, especially those concerning the enzymatic activities of the protein. This study probes the structure of hemoglobin (Hb), a model protein, confined inside silica tubes with pore diameters that vary by one order of magnitude (≈20-200 nm). The effect of confinement on the protein structure is probed by comparison with the structure of the protein in solution. Small-angle neutron scattering (SANS), which provides information on protein tertiary and quaternary structures, is employed to study the influence of the tube pore diameter on the structure and configuration of the confined protein in detail. Confinement significantly influences the structural stability of Hb and the structure depends on the Si-tube pore diameter. The high radius of gyration (Rg) and polydispersity of Hb in the 20 nm diameter Si-tube indicates that Hb undergoes a significant amount of aggregation. However, for Si-tube diameters greater or equal to 100 nm, the Rg of Hb is found to be in very close proximity to that obtained from the protein data bank (PDB) reported structure (Rg of native Hb=23.8 Å). This strongly indicates that the protein has a preference for the more native-like non-aggregated state if confined inside tubes of diameter greater or equal to 100 nm. Further insight into the Hb structure is obtained from the distance distribution function, p(r), and ab initio models calculated from the SANS patterns. These also suggest that the Si-tube size is a key parameter for protein stability and structure.
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Affiliation(s)
- Soumit S Mandal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012 (India), Fax: (+91) 80-23601310
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27
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Changeux JP. 50 years of allosteric interactions: the twists and turns of the models. Nat Rev Mol Cell Biol 2013; 14:819-29. [DOI: 10.1038/nrm3695] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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28
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Changeux JP. The concept of allosteric interaction and its consequences for the chemistry of the brain. J Biol Chem 2013; 288:26969-26986. [PMID: 23878193 DOI: 10.1074/jbc.x113.503375] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Throughout this Reflections article, I have tried to follow up on the genesis in the 1960s and subsequent evolution of the concept of allosteric interaction and to examine its consequences within the past decades, essentially in the field of the neuroscience. The main conclusion is that allosteric mechanisms built on similar structural principles operate in bacterial regulatory enzymes, gene repressors (and the related nuclear receptors), rhodopsin, G-protein-coupled receptors, neurotransmitter receptors, ion channels, and so on from prokaryotes up to the human brain yet with important features of their own. Thus, future research on these basic cybernetic sensors is expected to develop in two major directions: at the elementary level, toward the atomic structure and molecular dynamics of the conformational changes involved in signal recognition and transduction, but also at a higher level of organization, the contribution of allosteric mechanisms to the modulation of brain functions.
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Affiliation(s)
- Jean-Pierre Changeux
- Collège de France, 75005 Paris and the Institut Pasteur, 75724 Paris Cedex 15, France.
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29
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Inoguchi N, Oshlo JR, Natarajan C, Weber RE, Fago A, Storz JF, Moriyama H. Deer mouse hemoglobin exhibits a lowered oxygen affinity owing to mobility of the E helix. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:393-8. [PMID: 23545644 PMCID: PMC3614163 DOI: 10.1107/s1744309113005708] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 02/27/2013] [Indexed: 11/10/2022]
Abstract
The deer mouse, Peromyscus maniculatus, exhibits altitude-associated variation in hemoglobin oxygen affinity. To examine the structural basis of this functional variation, the structure of the hemoglobin was solved. Recombinant hemoglobin was expressed in Escherichia coli and was purified by ion-exchange chromatography. Recombinant hemoglobin was crystallized by the hanging-drop vapor-diffusion method using polyethylene glycol as a precipitant. The obtained orthorhombic crystal contained two subunits in the asymmetric unit. The refined structure was interpreted as the aquo-met form. Structural comparisons were performed among hemoglobins from deer mouse, house mouse and human. In contrast to human hemoglobin, deer mouse hemoglobin lacks the hydrogen bond between α1Trp14 in the A helix and α1Thr67 in the E helix owing to the Thr67Ala substitution. In addition, deer mouse hemoglobin has a unique hydrogen bond at the α1β1 interface between residues α1Cys34 and β1Ser128.
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Affiliation(s)
- Noriko Inoguchi
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Jake R. Oshlo
- Nebraska Wesleyan University, Lincoln, Nebraska, USA
| | | | - Roy E. Weber
- Zoophysiology, Department of Biological Sciences, Aarhus University, Aarhus, Denmark
| | - Angela Fago
- Zoophysiology, Department of Biological Sciences, Aarhus University, Aarhus, Denmark
| | - Jay F. Storz
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
| | - Hideaki Moriyama
- School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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30
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Marzen S, Garcia HG, Phillips R. Statistical mechanics of Monod-Wyman-Changeux (MWC) models. J Mol Biol 2013; 425:1433-60. [PMID: 23499654 DOI: 10.1016/j.jmb.2013.03.013] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 03/03/2013] [Accepted: 03/04/2013] [Indexed: 11/27/2022]
Abstract
The 50th anniversary of the classic Monod-Wyman-Changeux (MWC) model provides an opportunity to survey the broader conceptual and quantitative implications of this quintessential biophysical model. With the use of statistical mechanics, the mathematical implementation of the MWC concept links problems that seem otherwise to have no ostensible biological connection including ligand-receptor binding, ligand-gated ion channels, chemotaxis, chromatin structure and gene regulation. Hence, a thorough mathematical analysis of the MWC model can illuminate the performance limits of a number of unrelated biological systems in one stroke. The goal of our review is twofold. First, we describe in detail the general physical principles that are used to derive the activity of MWC molecules as a function of their regulatory ligands. Second, we illustrate the power of ideas from information theory and dynamical systems for quantifying how well the output of MWC molecules tracks their sensory input, giving a sense of the "design" constraints faced by these receptors.
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Affiliation(s)
- Sarah Marzen
- Department of Physics, University of California Berkeley, Berkeley, CA 94720-7300, USA
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31
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Tekpinar M, Zheng W. Coarse-grained and all-atom modeling of structural states and transitions in hemoglobin. Proteins 2012; 81:240-52. [PMID: 22987685 DOI: 10.1002/prot.24180] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 08/27/2012] [Accepted: 09/10/2012] [Indexed: 11/08/2022]
Abstract
Hemoglobin (Hb), an oxygen-binding protein composed of four subunits (α1, α2, β1, and β2), is a well-known example of allosteric proteins that are capable of cooperative ligand binding. Despite decades of studies, the structural basis of its cooperativity remains controversial. In this study, we have integrated coarse-grained (CG) modeling, all-atom simulation, and structural data from X-ray crystallography and wide-angle X-ray scattering (WAXS), aiming to probe dynamic properties of the two structural states of Hb (T and R state) and the transitions between them. First, by analyzing the WAXS data of unliganded and liganded Hb, we have found that the structural ensemble of T or R state is dominated by one crystal structure of Hb with small contributions from other crystal structures of Hb. Second, we have used normal mode analysis to identify two distinct quaternary rotations between the α1β1 and α2β2 dimer, which drive the transitions between T and R state. We have also identified the hot-spot residues whose mutations are predicted to greatly change these quaternary motions. Third, we have generated a CG transition pathway between T and R state, which predicts a clear order of quaternary and tertiary changes involving α and β subunits in Hb. Fourth, we have used the accelerated molecular dynamics to perform an all-atom simulation starting from the T state of Hb, and we have observed a transition toward the R state of Hb. Further analysis of crystal structural data and the all-atom simulation trajectory has corroborated the order of quaternary and tertiary changes predicted by CG modeling.
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Affiliation(s)
- Mustafa Tekpinar
- Physics Department, University at Buffalo, Buffalo, New York 14260, USA
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32
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Levantino M, Spilotros A, Cammarata M, Schirò G, Ardiccioni C, Vallone B, Brunori M, Cupane A. The Monod-Wyman-Changeux allosteric model accounts for the quaternary transition dynamics in wild type and a recombinant mutant human hemoglobin. Proc Natl Acad Sci U S A 2012; 109:14894-9. [PMID: 22927385 PMCID: PMC3443182 DOI: 10.1073/pnas.1205809109] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The acknowledged success of the Monod-Wyman-Changeux (MWC) allosteric model stems from its efficacy in accounting for the functional behavior of many complex proteins starting with hemoglobin (the paradigmatic case) and extending to channels and receptors. The kinetic aspects of the allosteric model, however, have been often neglected, with the exception of hemoglobin and a few other proteins where conformational relaxations can be triggered by a short and intense laser pulse, and monitored by time-resolved optical spectroscopy. Only recently the application of time-resolved wide-angle X-ray scattering (TR-WAXS), a direct structurally sensitive technique, unveiled the time scale of hemoglobin quaternary structural transition. In order to test the generality of the MWC kinetic model, we carried out a TR-WAXS investigation in parallel on adult human hemoglobin and on a recombinant protein (HbYQ) carrying two mutations at the active site [Leu(B10)Tyr and His(E7)Gln]. HbYQ seemed an ideal test because, although exhibiting allosteric properties, its kinetic and structural properties are different from adult human hemoglobin. The structural dynamics of HbYQ unveiled by TR-WAXS can be quantitatively accounted for by the MWC kinetic model. Interestingly, the main structural change associated with the R-T allosteric transition (i.e., the relative rotation and translation of the dimers) is approximately 10-fold slower in HbYQ, and the drop in the allosteric transition rate with ligand saturation is steeper. Our results extend the general validity of the MWC kinetic model and reveal peculiar thermodynamic properties of HbYQ. A possible structural interpretation of the characteristic kinetic behavior of HbYQ is also discussed.
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Affiliation(s)
- Matteo Levantino
- Department of Physics, University of Palermo, Via Archirafi 36, I-90123 Palermo, Italy
| | - Alessandro Spilotros
- Department of Physics, University of Palermo, Via Archirafi 36, I-90123 Palermo, Italy
| | - Marco Cammarata
- Institut de Physique de Rennes, Centre National de la Recherche Scientifique, 263 Avenue Général Leclerc, 35042 Rennes, France; and
| | - Giorgio Schirò
- Department of Physics, University of Palermo, Via Archirafi 36, I-90123 Palermo, Italy
| | - Chiara Ardiccioni
- Department of Biochemical Sciences, and Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza—University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Beatrice Vallone
- Department of Biochemical Sciences, and Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza—University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Maurizio Brunori
- Department of Biochemical Sciences, and Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza—University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Antonio Cupane
- Department of Physics, University of Palermo, Via Archirafi 36, I-90123 Palermo, Italy
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33
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Kim K, Muniyappan S, Oang KY, Kim JG, Nozawa S, Sato T, Koshihara SY, Henning R, Kosheleva I, Ki H, Kim Y, Kim TW, Kim J, Adachi SI, Ihee H. Direct observation of cooperative protein structural dynamics of homodimeric hemoglobin from 100 ps to 10 ms with pump-probe X-ray solution scattering. J Am Chem Soc 2012; 134:7001-8. [PMID: 22494177 PMCID: PMC3337689 DOI: 10.1021/ja210856v] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Indexed: 01/11/2023]
Abstract
Proteins serve as molecular machines in performing their biological functions, but the detailed structural transitions are difficult to observe in their native aqueous environments in real time. For example, despite extensive studies, the solution-phase structures of the intermediates along the allosteric pathways for the transitions between the relaxed (R) and tense (T) forms have been elusive. In this work, we employed picosecond X-ray solution scattering and novel structural analysis to track the details of the structural dynamics of wild-type homodimeric hemoglobin (HbI) from the clam Scapharca inaequivalvis and its F97Y mutant over a wide time range from 100 ps to 56.2 ms. From kinetic analysis of the measured time-resolved X-ray solution scattering data, we identified three structurally distinct intermediates (I(1), I(2), and I(3)) and their kinetic pathways common for both the wild type and the mutant. The data revealed that the singly liganded and unliganded forms of each intermediate share the same structure, providing direct evidence that the ligand photolysis of only a single subunit induces the same structural change as the complete photolysis of both subunits does. In addition, by applying novel structural analysis to the scattering data, we elucidated the detailed structural changes in the protein, including changes in the heme-heme distance, the quaternary rotation angle of subunits, and interfacial water gain/loss. The earliest, R-like I(1) intermediate is generated within 100 ps and transforms to the R-like I(2) intermediate with a time constant of 3.2 ± 0.2 ns. Subsequently, the late, T-like I(3) intermediate is formed via subunit rotation, a decrease in the heme-heme distance, and substantial gain of interfacial water and exhibits ligation-dependent formation kinetics with time constants of 730 ± 120 ns for the fully photolyzed form and 5.6 ± 0.8 μs for the partially photolyzed form. For the mutant, the overall kinetics are accelerated, and the formation of the T-like I(3) intermediate involves interfacial water loss (instead of water entry) and lacks the contraction of the heme-heme distance, thus underscoring the dramatic effect of the F97Y mutation. The ability to keep track of the detailed movements of the protein in aqueous solution in real time provides new insights into the protein structural dynamics.
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Affiliation(s)
- Kyung
Hwan Kim
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Srinivasan Muniyappan
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Key Young Oang
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Jong Goo Kim
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Shunsuke Nozawa
- Photon Factory,
Institute of
Materials Structure Science, High Energy Accelerator
Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki
305-0801, Japan
| | - Tokushi Sato
- Photon Factory,
Institute of
Materials Structure Science, High Energy Accelerator
Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki
305-0801, Japan
| | - Shin-ya Koshihara
- Department
of Chemistry and Materials
Science, Tokyo Institute of Technology and
CREST, Japan Science and Technology Agency (JST), Meguro-ku, Tokyo 152-8551, Japan
| | - Robert Henning
- Center for Advanced Radiation
Sources, The University of Chicago, Chicago,
Illinois 60637, United States
| | - Irina Kosheleva
- Center for Advanced Radiation
Sources, The University of Chicago, Chicago,
Illinois 60637, United States
| | - Hosung Ki
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Youngmin Kim
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Tae Wu Kim
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Jeongho Kim
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
| | - Shin-ichi Adachi
- Photon Factory,
Institute of
Materials Structure Science, High Energy Accelerator
Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki
305-0801, Japan
- PRESTO, Japan Science
and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi,
Saitama 332-0012, Japan
| | - Hyotcherl Ihee
- Center for Time-Resolved Diffraction,
Department of Chemistry, Graduate School of Nanoscience & Technology
(WCU), KAIST, Daejeon, 305-701, Republic
of Korea
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Jones EM, Balakrishnan G, Spiro TG. Heme reactivity is uncoupled from quaternary structure in gel-encapsulated hemoglobin: a resonance Raman spectroscopic study. J Am Chem Soc 2012; 134:3461-71. [PMID: 22263778 PMCID: PMC3307588 DOI: 10.1021/ja210126j] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Encapsulation of hemoglobin (Hb) in silica gel preserves structure and function but greatly slows protein motion, thereby providing access to intermediates along the allosteric pathway that are inaccessible in solution. Resonance Raman (RR) spectroscopy with visible and ultraviolet laser excitation provides probes of heme reactivity and of key tertiary and quaternary contacts. These probes were monitored in gels after deoxygenation of oxyHb and after CO binding to deoxyHb, which initiate conformational change in the R-T and T-R directions, respectively. The spectra establish that quaternary structure change in the gel takes a week or more but that the evolution of heme reactivity, as monitored by the Fe-histidine stretching vibration, ν(FeHis), is completed within two days, and is therefore uncoupled from the quaternary structure. Within each quaternary structure, the evolving ν(FeHis) frequencies span the full range of values between those previously associated with the high- and low-affinity end states, R and T. This result supports the tertiary two-state (TTS) model, in which the Hb subunits can adopt high- and low-affinity tertiary structures, r and t, within each quaternary state. The spectra also reveal different tertiary pathways, involving the breaking and reformation of E and F interhelical contacts in the R-T direction but not the T-R direction. In the latter, tertiary motions are restricted by the T quaternary contacts.
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Affiliation(s)
- Eric M. Jones
- Department of Chemistry, University of Washington, Box 351700, Seattle Washington 98195-1700 USA
| | - Gurusamy Balakrishnan
- Department of Chemistry, University of Washington, Box 351700, Seattle Washington 98195-1700 USA
| | - Thomas G. Spiro
- Department of Chemistry, University of Washington, Box 351700, Seattle Washington 98195-1700 USA
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35
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Abstract
The Monod-Wyman-Changeux (MWC) model was conceived in 1965 to account for the signal transduction and cooperative properties of bacterial regulatory enzymes and hemoglobin. It was soon extended to pharmacological receptors for neurotransmitters and other macromolecular entities involved in intracellular and intercellular communications. Five decades later, the two main hypotheses of the model are reexamined on the basis of a variety of regulatory proteins with known X-ray structures: (a) Regulatory proteins possess an oligomeric structure with symmetry properties, and (b) the allosteric interactions between topographically distinct sites are mediated by a conformational transition established between a few preestablished states with conservation of symmetry and ligand-directed conformational selection. Several well-documented examples are adequately represented by the MWC model, yet a few possible exceptions are noted. New questions are raised concerning the dynamics of the allosteric transitions and more complex supramolecular ensembles.
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Affiliation(s)
- Jean-Pierre Changeux
- Collège de France & Institut Pasteur, URA CNRS 2182, Paris Cedex 15 75724, France.
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36
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Changeux JP, Edelstein S. Conformational selection or induced fit? 50 years of debate resolved. F1000 BIOLOGY REPORTS 2011; 3:19. [PMID: 21941598 PMCID: PMC3169905 DOI: 10.3410/b3-19] [Citation(s) in RCA: 183] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Exactly 50 years ago, biochemists raised the question of the mechanism of the conformational change that mediates “allosteric” interactions between regulatory sites and biologically active sites in regulatory/receptor proteins. Do the different conformations involved already exist spontaneously in the absence of the regulatory ligands (Monod-Wyman-Changeux), such that the complementary protein conformation would be selected to mediate signal transduction, or do particular ligands induce the receptor to adopt the conformation best suited to them (Koshland-Nemethy-Filmer—induced fit)? This is not just a central question for biophysics, it also has enormous importance for drug design. Recent advances in techniques have allowed detailed experimental and theoretical comparisons with the formal models of both scenarios. Also, it has been shown that mutated receptors can adopt constitutively active confirmations in the absence of ligand. There have also been demonstrations that the atomic resolution structures of the same protein are essentially the same whether ligand is bound or not. These and other advances in past decades have produced a situation where the vast majority of the data using different categories of regulatory proteins (including regulatory enzymes, ligand-gated ion channels, G protein-coupled receptors, and nuclear receptors) support the conformational selection scheme of signal transduction.
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Affiliation(s)
- Jean-Pierre Changeux
- Collège de France and Institut PasteurCNRS URA 2182, 25 rue du Dr Roux, 75015 ParisFrance
| | - Stuart Edelstein
- European Bioinformatics Institute and University of GenevaWellcome Trust Genome Campus, Hinxton, CB10 1SDUK
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37
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Bellavia G, Giuffrida S, Cottone G, Cupane A, Cordone L. Protein thermal denaturation and matrix glass transition in different protein-trehalose-water systems. J Phys Chem B 2011; 115:6340-6. [PMID: 21488647 DOI: 10.1021/jp201378y] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Biopreservation by saccharides is a widely studied issue due to its scientific and technological importance; in particular, ternary amorphous protein-saccharide-water systems are extensively exploited to model the characteristics of the in vivo biopreservation process. We present here a differential scanning calorimetry (DSC) study on amorphous trehalose-water systems with embedded different proteins (myoglobin, lysozyme, BSA, hemoglobin), which differ for charge, surface, and volume properties. In our study, the protein/trehalose molar ratio is kept constant at 1/40, while the water/sugar molar ratio is varied between 2 and 300; results are compared with those obtained for binary trehalose-water systems. DSC upscans offer the possibility of investigating, in the same measurement, the thermodynamic properties of the matrix (glass transition, T(g)) and the functional properties of the encapsulated protein (thermal denaturation, T(den)). At high-to-intermediate hydration, the presence of the proteins increases the glass transition temperature of the encapsulating matrix. The effect mainly depends on size properties, and it can be ascribed to confinement exerted by the protein on the trehalose-water solvent. Conversely, at low hydration, lower T(g) values are measured in the presence of proteins: the lack of water promotes sugar-protein interactions, thus weakening the confinement effect and softening the matrix with respect to the binary system. A parallel T(den) increase is also observed; remarkably, this stabilization can reach ∼70 K at low hydration, a finding potentially of high biotechnological relevance. A linear relationship between T(g) and T(den) is also observed, in line with previous results; this finding suggests that collective water-trehalose interactions, responsible for the glass transition, also influence the protein denaturation.
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Affiliation(s)
- Giuseppe Bellavia
- Dipartimento di Fisica, Università di Palermo and CNISM,Via Archirafi 36, I-90123 Palermo, Italy
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38
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Abstract
Large conformational transitions play an essential role in the function of many proteins, but experiments do not provide the atomic details of the path followed in going from one end structure to the other. For the hemoglobin tetramer, the transition path between the unliganded (T) and tetraoxygenated (R) structures is not known, which limits our understanding of the cooperative mechanism in this classic allosteric system, where both tertiary and quaternary changes are involved. The conjugate peak refinement algorithm is used to compute an unbiased minimum energy path at atomic detail between the two end states. Although the results confirm some of the proposals of Perutz [Perutz MF (1970) Stereochemistry of cooperative effects in haemoglobin. Nature 228:726-734], the subunit motions do not follow the textbook description of a simple rotation of one αβ-dimer relative to the other. Instead, the path consists of two sequential quaternary rotations, each involving different subdomains and axes. The quaternary transitions are preceded and followed by phases of tertiary structural changes. The results explain the recent photodissociation measurements, which suggest that the quaternary transition has a fast (2 μs) as well as a slow (20 μs) component and provide a testable model for single molecule FRET experiments.
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39
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Affiliation(s)
- Thomas G Spiro
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA.
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