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Tsuneshige A, Tokoro T. Cooperative oxygen binding in beta-semihemoglobins caused by a chemical modification in the alpha1beta1 interface. J Inorg Biochem 2023; 246:112264. [PMID: 37290360 DOI: 10.1016/j.jinorgbio.2023.112264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/25/2023] [Accepted: 05/20/2023] [Indexed: 06/10/2023]
Abstract
A beta-semihemoglobin is an alpha-beta dimer of hemoglobin (Hb) in which the beta-subunit carries heme, while the alpha-subunit is heme-less, in apo form. It is characterised by displaying a high affinity for oxygen, and absence of cooperative binding of oxygen. We have modified chemically the residue beta112Cys (G14), located adjacent to the alpha1beta1 interface, and studied the impact of such a modification on the oligomeric state and oxygenation properties of the derivatives. We also studied the impact of modifying beta93Cys (F9) since its modification was unavoidable. For this, we used N-Ethyl maleimide and iodoacetamide. For the alkylation of beta112Cys (G14) in isolated subunits, we used N-Ethyl maleimide, iodoacetamide, or additionally, 4,4'-Dithiopyridine. Seven native and chemically modified beta-subunit derivatives were prepared and analysed. Only those derivatives treated with iodoacetamide showed oxygenation properties that were indistinguishable from those of native beta-subunits. These derivatives were then converted into their respective semihemoglobin forms, and four additional derivatives were prepared and analysed .in terms of ligation-linked oligomeric state, and oxygenation function, and contrasted against native Hb and unmodified beta-subunits. Strikingly, beta-semiHbs with modifications in beta112Cys showed indications of cooperative oxygen binding in various degrees, which suggested the possibility of assembly of two beta-semiHbs. The derivative modified with 4-Thiopyridine in beta112Cys showed a highly cooperative binding of oxygen (nmax = 1.67). A plausible allosteric scheme that could explain allostery in beta-semiHb system is suggested.
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Affiliation(s)
- Antonio Tsuneshige
- Department of Frontier Bioscience, Faculty of Bioscience and Applied Chemistry, Hosei University, Tokyo 184-8584, Japan; Research Center for Micro-Nano Technology, Hosei University, Tokyo 184-0003, Japan.
| | - Tatsunori Tokoro
- Department of Frontier Bioscience, Faculty of Bioscience and Applied Chemistry, Hosei University, Tokyo 184-8584, Japan
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2
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Ciaccio C, Coletta A, Coletta M. Role of hemoglobin structural-functional relationships in oxygen transport. Mol Aspects Med 2021; 84:101022. [PMID: 34509280 DOI: 10.1016/j.mam.2021.101022] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 09/02/2021] [Accepted: 09/03/2021] [Indexed: 10/20/2022]
Abstract
The molecular mechanism of O2 binding to hemoglobin (Hb) has been critically reviewed on the basis of the information built up in the last decades. It allows to describe in detail from the kinetic and thermodynamic viewpoint the process of O2 uptake in the lungs and release to the tissues, casting some light on the physiological and pathological aspects of this process. The relevance of structural-functional relationships for O2 binding is particularly outlined in the case of poorly vascularized tissues, such as retina, briefly discussing of strategies employed for optimization of oxygen supply to this type of tissues.
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Affiliation(s)
- Chiara Ciaccio
- Department of Clinical Sciences and Translational Medicine, University of Roma Tor Vergata, Via Montpellier 1, I-00133 Roma, Italy
| | | | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Roma Tor Vergata, Via Montpellier 1, I-00133 Roma, Italy; IRCCS Fondazione Bietti, Rome, Italy.
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3
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Oxygen dissociation from ferrous oxygenated human hemoglobin:haptoglobin complexes confirms that in the R-state α and β chains are functionally heterogeneous. Sci Rep 2019; 9:6780. [PMID: 31043649 PMCID: PMC6494993 DOI: 10.1038/s41598-019-43190-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 04/15/2019] [Indexed: 01/25/2023] Open
Abstract
The adverse effects of extra-erythrocytic hemoglobin (Hb) are counterbalanced by several plasma proteins devoted to facilitate the clearance of free heme and Hb. In particular, haptoglobin (Hp) traps the αβ dimers of Hb, which are delivered to the reticulo-endothelial system by CD163 receptor-mediated endocytosis. Since Hp:Hb complexes show heme-based reactivity, kinetics of O2 dissociation from the ferrous oxygenated human Hp1-1:Hb and Hp2-2:Hb complexes (Hp1-1:Hb(II)-O2 and Hp2-2:Hb(II)-O2, respectively) have been determined. O2 dissociation from Hp1-1:Hb(II)-O2 and Hp2-2:Hb(III)-O2 follows a biphasic process. The relative amplitude of the fast and slow phases ranges between 0.47 and 0.53 of the total amplitude, with values of koff1 (ranging between 25.6 ± 1.4 s-1 and 29.1 ± 1.3 s-1) being about twice faster than those of koff2 (ranging between 13.8 ± 1.6 s-1 and 16.1 ± 1.2 s-1). Values of koff1 and koff2 are essentially the same independently on whether O2 dissociation has been followed after addition of a dithionite solution or after O2 displacement by a CO solution in the presence of dithionite. They correspond to those reported for the dissociation of the first O2 molecule from tetrameric Hb(II)-O2, indicating that in the R-state α and β chains are functionally heterogeneous and the tetramer and the dimer behave identically. Accordingly, the structural conformation of the α and β chains of the Hb dimer bound to Hp corresponds to that of the subunits of the Hb tetramer in the R-state.
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4
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Manipulating hemoglobin oxygenation using silica nanoparticles: a novel prospect for artificial oxygen carriers. Blood Adv 2019; 2:90-94. [PMID: 29365316 DOI: 10.1182/bloodadvances.2017012153] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/14/2017] [Indexed: 12/23/2022] Open
Abstract
Recently, nanoparticles have attracted much attention as new scaffolds for hemoglobin-based oxygen carriers (HBOCs). Indeed, the development of bionanotechnology paves the way for the rational design of blood substitutes, providing that the interaction between the nanoparticles and hemoglobin at a molecular scale and its effect on the oxygenation properties of hemoglobin are finely controlled. Here, we show that human hemoglobin has a high affinity for silica nanoparticles, leading to the adsorption of hemoglobin tetramers on the surface. The adsorption process results in a remarkable retaining of the oxygenation properties of human adult hemoglobin and sickle cell hemoglobin, associated with an increase of the oxygen affinity. The cooperative oxygen binding exhibited by adsorbed hemoglobin and the comparison with the oxygenation properties of diaspirin cross-linked hemoglobin confirmed the preservation of the tetrameric structure of hemoglobin loaded on silica nanoparticles. Our results show that silica nanoparticles can act as an effector for human native and mutant hemoglobin. Manipulating hemoglobin oxygenation using nanoparticles opens the way to the design of novel HBOCs.
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Proteomic Analysis of Thiol Modifications and Assessment of Structural Changes in Hemoglobin Induced by the Aniline Metabolites N-Phenylhydroxylamine and Nitrosobenzene. Sci Rep 2017; 7:14794. [PMID: 29093547 PMCID: PMC5665987 DOI: 10.1038/s41598-017-14653-w] [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: 01/10/2017] [Accepted: 10/13/2017] [Indexed: 11/19/2022] Open
Abstract
MS-based proteomic analysis was combined with in silico quantum mechanical calculations to improve understanding of protein adduction by N-phenylhydroxylamine (PhNHOH) and nitrosobenzene (NOB), metabolic products of aniline. In vitro adduction of model peptides containing nucleophilic sidechains (Cys, His, and Lys) and selected proteins (bovine and human hemoglobin and β-lactoglobulin-A) were characterized. Peptide studies identified the Cys thiolate as the most reactive nucleophile for these metabolites, a result consistent with in silico calculations of reactivity parameters. For PhNHOH, sulfinamides were identified as the primary adduction products, which were stable following tryptic digestion. Conversely, reactions with NOB yielded an additional oxidized adduct, the sulfonamide. In vitro exposure of human whole blood to PhNHOH and NOB demonstrated that only sulfinamides were formed. In addition to previously reported adduction of β93Cys of human Hb, two novel sites of adduction were found; α104Cys and β112Cys. We also report CD and UV-Vis spectroscopy studies of adducted human Hb that revealed loss of α-helical content and deoxygenation. The results provide additional understanding of the covalent interaction of aromatic amine metabolites with protein nucleophiles.
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6
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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: 108] [Impact Index Per Article: 15.4] [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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7
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Devineau S, Zargarian L, Renault JP, Pin S. Structure and Function of Adsorbed Hemoglobin on Silica Nanoparticles: Relationship between the Adsorption Process and the Oxygen Binding Properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:3241-3252. [PMID: 28263607 DOI: 10.1021/acs.langmuir.6b04281] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The connection between the mechanisms of protein adsorption on nanoparticles and the structural and functional properties of the adsorbed protein often remains unclear. We investigate porcine hemoglobin adsorption on silica nanoparticles, and we analyze the structural and functional modifications of adsorbed hemoglobin by UV-vis spectrophotometry, circular dichroism, and oxygen binding measurement. The structural analysis of adsorbed hemoglobin on silica nanoparticles reveals a significant loss of secondary structure and a preservation of the heme electronic structure. However, adsorbed hemoglobin retains its quaternary structure and exhibits an enhanced oxygen affinity with cooperative binding. Moreover, the structural and functional modifications are fully reversible after complete desorption from silica nanoparticles at pH 8.7. The tunable adsorption and desorption of hemoglobin on SNPs with pH change, and the full control of hemoglobin activity by pH, temperature, and the addition of inorganic phosphate effectors opens the way to an interesting system whereby protein adsorption on nanoparticles can allow for full control over hemoglobin oxygen binding activity. Our results suggest that adsorption of hemoglobin on silica nanoparticles leads to a new structural, functional, and dynamic state with full reversibility in a way that significantly differs from protein denaturation.
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Affiliation(s)
- Stéphanie Devineau
- LIONS, NIMBE, CEA, CNRS, Université Paris-Saclay , CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Loussiné Zargarian
- LBPA, ENS de Cachan, CNRS, Université Paris-Saclay , 94235 Cachan Cedex, France
| | - Jean Philippe Renault
- LIONS, NIMBE, CEA, CNRS, Université Paris-Saclay , CEA Saclay, 91191 Gif-sur-Yvette, France
| | - Serge Pin
- LIONS, NIMBE, CEA, CNRS, Université Paris-Saclay , CEA Saclay, 91191 Gif-sur-Yvette, France
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8
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Zhao Q. A thermodynamic and theoretical view for enzyme regulation. BIOCHEMISTRY (MOSCOW) 2015; 80:1-7. [DOI: 10.1134/s0006297915010010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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Kadirvelraj R, Custer GS, Keul ND, Sennett NC, Sidlo AM, Walsh RM, Wood ZA. Hysteresis in human UDP-glucose dehydrogenase is due to a restrained hexameric structure that favors feedback inhibition. Biochemistry 2014; 53:8043-51. [PMID: 25478983 DOI: 10.1021/bi500594x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Human UDP-α-d-glucose-6-dehydrogenase (hUGDH) displays hysteresis because of a slow isomerization from an inactive state (E*) to an active state (E). Here we show that the structure of E* constrains hUGDH in a conformation that favors feedback inhibition at physiological pH. The feedback inhibitor UDP-α-d-xylose (UDP-Xyl) competes with the substrate UDP-α-d-glucose for the active site. Upon binding, UDP-Xyl triggers an allosteric switch that changes the structure and affinity of the intersubunit interface to form a stable but inactive horseshoe-shaped hexamer. Using sedimentation velocity studies and a new crystal structure, we show that E* represents a stable conformational intermediate between the active and feedback-inhibited conformations. Because the allosteric switch occludes the cofactor and substrate binding sites in the inactive hexamer, the intermediate conformation observed in the crystal structure is consistent with the E* transient observed in relaxation studies. Steady-state analysis shows that the E* conformation enhances the affinity of hUGDH for the allosteric inhibitor UDP-Xyl by 8.6-fold (Ki = 810 nM). We present a model in which the constrained quaternary structure permits a small effector molecule to leverage a disproportionately large allosteric response.
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Affiliation(s)
- Renuka Kadirvelraj
- Department of Biochemistry & Molecular Biology, University of Georgia , Athens, Georgia 30602, United States
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10
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O'Neill JS, Feeney KA. Circadian redox and metabolic oscillations in mammalian systems. Antioxid Redox Signal 2014; 20:2966-81. [PMID: 24063592 PMCID: PMC4038991 DOI: 10.1089/ars.2013.5582] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Accepted: 09/25/2013] [Indexed: 01/06/2023]
Abstract
SIGNIFICANCE A substantial proportion of mammalian physiology is organized around the day/night cycle, being regulated by the co-ordinated action of numerous cell-autonomous circadian oscillators throughout the body. Disruption of internal timekeeping, by genetic or environmental perturbation, leads to metabolic dysregulation, whereas changes in metabolism affect timekeeping. RECENT ADVANCES While gene expression cycles are essential for the temporal coordination of normal physiology, it has become clear that rhythms in metabolism and redox balance are cell-intrinsic phenomena, which may regulate gene expression cycles reciprocally, but persist in their absence. For example, a circadian rhythm in peroxiredoxin oxidation was recently observed in isolated human erythrocytes, fibroblast cell lines in vitro, and mouse liver in vivo. CRITICAL ISSUES Mammalian timekeeping is a cellular phenomenon. While we understand many of the cellular systems that contribute to this biological oscillation's fidelity and robustness, a comprehensive mechanistic understanding remains elusive. Moreover, the formerly clear distinction between "core clock components" and rhythmic cellular outputs is blurred since several outputs, for example, redox balance, can feed back to regulate timekeeping. As with any cyclical system, establishing causality becomes problematic. FUTURE DIRECTIONS A detailed molecular understanding of the temporal crosstalk between cellular systems, and the coincidence detection mechanisms that allow a cell to discriminate clock-relevant from irrelevant stimuli, will be essential as we move toward an integrated model of how this daily biological oscillation works. Such knowledge will highlight new avenues by which the functional consequences of circadian timekeeping can be explored in the context of human health and disease.
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Affiliation(s)
- John S O'Neill
- MRC Laboratory of Molecular Biology , Cambridge, United Kingdom
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11
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Shibayama N, Sugiyama K, Tame JRH, Park SY. Capturing the Hemoglobin Allosteric Transition in a Single Crystal Form. J Am Chem Soc 2014; 136:5097-105. [DOI: 10.1021/ja500380e] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Naoya Shibayama
- Division
of Biophysics, Department of Physiology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
| | - Kanako Sugiyama
- Drug
Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Tsurumi, Yokohama, 230-0045, Japan
| | - Jeremy R. H. Tame
- Drug
Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Tsurumi, Yokohama, 230-0045, Japan
| | - Sam-Yong Park
- Drug
Design Laboratory, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro, Tsurumi, Yokohama, 230-0045, Japan
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12
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Abstract
Circadian (∼24 hour) clocks are fundamentally important for coordinated physiology in organisms as diverse as cyanobacteria and humans. All current models of the molecular circadian clockwork in eukaryotic cells are based on transcription-translation feedback loops. Non-transcriptional mechanisms in the clockwork have been difficult to study in mammalian systems. We circumvented these problems by developing novel assays using human red blood cells, which have no nucleus (or DNA) and therefore cannot perform transcription. Our results show that transcription is not required for circadian oscillations in humans, and that non-transcriptional events seem to be sufficient to sustain cellular circadian rhythms. Using red blood cells, we found that peroxiredoxins, highly conserved antioxidant proteins, undergo ∼24-hour redox cycles, which persist for many days under constant conditions (that is, in the absence of external cues). Moreover, these rhythms are entrainable (that is, tunable by environmental stimuli) and temperature-compensated, both key features of circadian rhythms. We anticipate that our findings will facilitate more sophisticated cellular clock models, highlighting the interdependency of transcriptional and non-transcriptional oscillations in potentially all eukaryotic cells.
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Affiliation(s)
- John S. O’Neill
- Department of Clinical Neurosciences, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Addenbrooke’s Hospital, Cambridge CB2 0QQ, United Kingdom
| | - Akhilesh B. Reddy
- Department of Clinical Neurosciences, University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Addenbrooke’s Hospital, Cambridge CB2 0QQ, United Kingdom
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13
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Asmundson AL, Taber AM, van der Walde A, Lin DH, Olson JS, Anthony-Cahill SJ. Coexpression of human alpha- and circularly permuted beta-globins yields a hemoglobin with normal R state but modified T state properties. Biochemistry 2009; 48:5456-65. [PMID: 19397368 DOI: 10.1021/bi900216p] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
For the first time, a circularly permuted human beta-globin (cpbeta) has been coexpressed with human alpha-globin in bacterial cells and shown to associate to form alpha-cpbeta hemoglobin in solution. Flash photolysis studies of alpha-cpbeta show markedly biphasic CO and O(2) kinetics with the amplitudes for the fast association phases being dominant due the presence of large amounts of high-affinity liganded hemoglobin dimers. Extensive dimerization of liganded but not deoxygenated alpha-cpbeta was observed by gel chromatography. The rate constants for O(2) and CO binding to the R state forms of alpha-cpbeta are almost identical to those of native HbA (k'(R(CO)) approximately 5.0 microM(-1) s(-1); k'(R(O(2))) approximately 50 microM(-1) s(-1)), and the rate of O(2) dissociation from fully oxygenated alpha-cpbeta is also very similar to that observed for HbA (k(R(O(2))) approximately 21-28 s(-1)). When the equilibrium deoxyHb form of alpha-cpbeta is reacted with CO in rapid mixing experiments, the observed time courses are monophasic and the observed bimolecular association rate constant is approximately 1.0 microM(-1) s(-1), which is intermediate between the R state rate measured in partial photolysis experiments (approximately 5 microM(-1) s(-1)) and that observed for T state deoxyHbA (k'(T(CO)) approximately 0.1 to 0.2 microM(-1) s(-1)). Thus the deoxygenated permutated beta subunits generate an intermediate, higher affinity, deoxyHb quaternary state. This conclusion is supported by equilibrium oxygen binding measurements in which alpha-cpbeta exhibits a P(50) of approximately 1.5 mmHg and a low n-value (approximately 1.3) at pH 7, 20 degrees C, compared to 8.5 mmHg and n approximately 2.8 for native HbA under identical, dilute conditions.
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Affiliation(s)
- Anna L Asmundson
- Department of Chemistry, Western Washington University, Bellingham, Washington 98225-9150, USA
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14
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Harris DR, Palmer AF. Modern cross-linking strategies for synthesizing acellular hemoglobin-based oxygen carriers. Biotechnol Prog 2009; 24:1215-25. [PMID: 19194934 DOI: 10.1002/btpr.85] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Unmodified cell-free hemoglobin (Hb) is structurally unstable when transfused into the blood stream (Valeri et al., Artif Cells Blood Substit Immobil Biotechnol. 2000;28:451-475; Chan et al., Toxicol Pathol. 2000;28:635-642; Eike, Dissertation, 2005; Eike and Palmer, Biotechnol Prog. 2004;20:946-952). This review examines some of the latest chemical strategies used over the last 5 years to intra- and intermolecularly cross-link Hb, thereby stabilizing its quaternary structure. Therefore, this work will address the following aspects: (1) site-specific chemical modifications of Hb and (2) non-site-specific chemical modifications of Hb, including, but not limited to, PolyHeme, Hemopure, Oxyglobin, and SOD-Hb. Current strategies for synthesizing PEGylated Hb is outside the scope of this review and will not be discussed herein. For a more thorough review of PEGylated Hb, the reader is directed to the following works: Cabrales and Friedman, Transfus Alternatives in Transfus Med. 2007;9:281-293 and Winslow, Biochim Biophys Acta, 2008;1784(10):1382-1386.
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Affiliation(s)
- David Raphael Harris
- Dept. of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, OH 43210, USA
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15
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Ciaccio C, Coletta A, De Sanctis G, Marini S, Coletta M. Cooperativity and allostery in haemoglobin function. IUBMB Life 2008; 60:112-23. [DOI: 10.1002/iub.6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Bonafe CF, Matsukuma AY, Matsuura MS. ATP-induced tetramerization and cooperativity in hemoglobin of lower vertebrates. J Biol Chem 1999; 274:1196-8. [PMID: 9880485 DOI: 10.1074/jbc.274.3.1196] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The importance of intraerythrocytic organic phosphates in the allosteric control of oxygen binding to vertebrate hemoglobin (Hb) is well recognized and is correlated with conformational changes of the tetramer. ATP is a major allosteric effector of snake Hb, since the absence of this nucleotide abolishes the Hb cooperativity. This effect may be related to the molecular weight of about 32,000 for this Hb, which is compatible with the dimeric form. ATP induces a pH-dependent tetramerization of deoxyHb that leads to the recovery of cooperativity. This phenomenon may be partially explained by two amino acid replacements in the beta chains (CD2 Glu-43 --> Thr and G3 Glu-101 --> Val), which result in the loss of two negative charges at the alpha1beta2 interface and favors the dissociation into dimers. The ATP-dependent dimer left arrow over right arrow tetramer may be physiologically important among ancient animal groups that have similar mutations and display variations in blood pH that are governed by these animals' metabolic state. The enormous loss of free energy of association that accompanies Hb oxygenation, and which is also observed at a much lower intensity in higher vertebrate Hbs, must be taken into consideration in allosteric models. We propose that the transition from a myoglobin-like protein to an allosteric one may be of evolutionary significance.
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Affiliation(s)
- C F Bonafe
- Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas, 13083-970, Campinas, São Paulo, Brazil
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17
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Brittain T. Role of dimerization in the control of the functioning of the human haemoglobin mutant haemoglobin Howick (beta 37 Trp-->Gly). Biochem J 1994; 300 ( Pt 2):553-6. [PMID: 8002962 PMCID: PMC1138197 DOI: 10.1042/bj3000553] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Haemoglobin Howick shows a high oxygen affinity (p50 = 1 mmHg) and a low co-operativity (n = 1.3). Equilibrium studies show the protein to be essentially totally dimeric in the oxygenated form. A wide range of rapid kinetic experiments indicate that the deoxygenated form of the protein exists in a tetramer<-->dimer equilibrium with an associated equilibrium constant of 3 microM. These kinetic data also indicate that the oxygenated form of the protein exists in a tetramer<-->dimer equilibrium with an associated equilibrium constant of 35 mM, and furthermore clearly identifies a large increase in the rate of the tetramer-to-dimer dissociation process as the origin of the vastly increased dissociation equilibrium constants. Simulations of the protein-concentration-dependence of the oxygen-binding properties of haemoglobin Howick, based on the measured equilibrium parameters, closely fits the experimental data. The change in dimerization constant for the deoxygenated form of the protein corresponds remarkably well to the free-energy change predicted for the simple transfer of the amino acid side chain at position beta 37 from a hydrophobic to a hydrophilic environment during the dimerization process.
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Affiliation(s)
- T Brittain
- Department of Biochemistry, University of Auckland, New Zealand
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18
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Shibayama N, Imai K, Morimoto H, Saigo S. Oxygen equilibrium properties of asymmetric nickel(II)-iron(II) hybrid hemoglobin. Biochemistry 1993; 32:8792-8. [PMID: 8364027 DOI: 10.1021/bi00085a009] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Asymmetric Ni(II)-Fe(II) hybrid hemoglobin, XL[alpha(Fe)beta(Fe)][alpha(Ni)beta(Ni)], in which the alpha 1 beta 1 dimer containing ferrous protoporphyrin IX and the complementary alpha 2 beta 2 dimer containing Ni(II) protoporphyrin IX were cross-linked between Lys-82 beta 1 and Lys-82 beta 2 by reaction with bis(3,5-dibromosalicyl) fumarate, was synthesized and characterized. We have previously shown that (i) Ni(II) protoporphyrin IX, which binds neither oxygen nor carbon monoxide, mimics a fixed deoxyheme with respect to its effect on the oxygen equilibrium properties of the counterpart iron subunits in both symmetric Ni(II)-Fe(II) hybrid Hbs [Shibayama, N., Morimoto, H., & Miyazaki, G. (1986) J. Mol. Biol. 192, 323-329] and (ii) the cross-linking used in this study little affects the oxygen equilibrium properties of hemoglobin [Shibayama, N., Imai, K., Hirata, H., Hiraiwa, H., Morimoto, H., & Saigo, S. (1991) Biochemistry 30, 8158-8165]. These remarkable features of our model allowed us to measure the oxygen equilibrium curves for the first two steps of oxygen binding to the alpha 1 beta 1 dimer within the hemoglobin tetramer. At all pH values examined, the affinities of this asymmetric hybrid for the first oxygen molecule are as low as those of native hemoglobin. The hybrid did not show cooperative oxygen binding at pH 6.4, while significant cooperativity was observed with rising pH; i.e., the Hill coefficient was increased from 1.41 to 1.53 upon a pH change from 7.4 to 8.4. The electronic absorption spectrum of Ni(II) protoporphyrin IX in the alpha 2 subunit was changed upon carbon monoxide (or oxygen) binding to the alpha 1 beta 1 dimer.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- N Shibayama
- Department of Physics, Jichi Medical School, Tochigi, Japan
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19
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Doyle ML, Lew G, Turner GJ, Rucknagel D, Ackers GK. Regulation of oxygen affinity by quaternary enhancement: does hemoglobin Ypsilanti represent an allosteric intermediate? Proteins 1992; 14:351-62. [PMID: 1438174 DOI: 10.1002/prot.340140304] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Recent crystallographic studies on the mutant human hemoglobin Ypsilanti (beta 99 Asp-->Tyr) have revealed a previously unknown quaternary structure called "quaternary Y" and suggested that the new structure may represent an important intermediate in the cooperative oxygenation pathway of normal hemoglobin. Here we measure the oxygenation and subunit assembly properties of hemoglobin Ypsilanti and five additional beta 99 mutants (Asp beta 99-->Val, Gly, Asn, Ala, His) to test for consistency between their energetics and those of the intermediate species of normal hemoglobin. Overall regulation of oxygen affinity in hemoglobin Ypsilanti is found to originate entirely from 2.6 kcal of quaternary enhancement, such that the tetramer oxygenation affinity is 85-fold higher than for binding to the dissociated dimers. Equal partitioning of this regulatory energy among the four tetrameric binding steps (0.65 kcal per oxygen) leads to a noncooperative isotherm with extremely high affinity (pmedian = .14 torr). Temperature and pH studies of dimer-tetramer assembly and sulfhydryl reaction kinetics suggest that oxygenation-dependent structural changes in hemoglobin Ypsilanti are small. These properties are quite different from the recently characterized allosteric intermediate, which has two ligands bound on the same side of the alpha 1 beta 2 interface (see ref. 1 for review). The combined results do, however, support the view that quaternary Y may represent the intermediate cooperativity state of normal hemoglobin that binds the last oxygen.
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Affiliation(s)
- M L Doyle
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110
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20
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Ackers GK, Johnson ML. Analysis of hemoglobin oxygenation from combined equilibrium and kinetic data. Is quaternary enhancement necessary? Biophys Chem 1990; 37:265-79. [PMID: 2285788 DOI: 10.1016/0301-4622(90)88026-o] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
An experimental approach based on four independent techniques, in which kinetic and equilibrium measurements of subunit assembly reactions are combined with concentration-dependent oxygen-binding curves, has previously been used to resolve parameters of the linkage system for human hemoglobin over a wide range of conditions [(G.K. Ackers and H.R. Halvorson, Proc. Natl. Acad. Sci. U.S.A. 71 (1974) 4312; F.C. Mills et al., Biochemistry 15 (1976) 1093; M.L. Johnson et al., Biochemistry 15 (1976) 5363). Throughout this extensive body of results it has been found that the affinity for binding oxygen to tetramers at the fourth step exceeds the mean affinity of dissociated dimers. The existence of this "quaternary enhancement" effect has recently been questioned by Gibson and Edelstein (J. Biol. Chem. 262 (1987) 516) and by Philo and Lary (J. Biol. Chem. 265 (1990) 139) on the basis of kinetically derived oxygen-binding constants that do not exhibit quaternary enhancement. These authors have also suggested that quaternary enhancement might not be necessary to explain the oxygen-binding data mentioned above. In this study, we have explored the effect of constraining the numerical analysis of oxygen-binding data against the new kinetically derived binding constants. It is found that the sets of linkage constants which are compatible with both the oxygen-binding data and the new kinetically derived dimer binding constant require both quaternary enhancement and substantial dimer cooperativity. Increasing the dimer cooperativity to compensate completely for quaternary enhancement requires both dimeric and tetrameric binding constants that disagree with the kinetically derived values. Thus, the quaternary enhancement effect cannot be eliminated by readjustment of the remaining constants of the linkage system. Possible sources of the discrepancy between the kinetically derived binding constants and the otherwise self-consistent data from the other four techniques are discussed.
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Affiliation(s)
- G K Ackers
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110
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21
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Smith SE, Brittain T, Wells RM. A kinetic and equilibrium study of ligand binding to the monomeric and dimeric haem-containing globins of two chitons. Biochem J 1988; 252:673-8. [PMID: 3421917 PMCID: PMC1149201 DOI: 10.1042/bj2520673] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The radular muscles of the amphineuran molluscs Amaurochiton glaucus and Sipharochiton pelliserpentis contain both a dimeric and a monomeric form of myoglobin. The dimeric form of the protein is composed of two polypeptide chains covalently linked to each other via one or more disulphide bonds. The dimeric protein shows co-operative O2-binding curves. Kinetic investigations indicate that CO binding is co-operative in the dimeric protein, subsequent to full photolysis, but mono-exponential following 10% photolysis. O2 recombination following part photolysis is mono-exponential in the dimeric form, whereas O2 dissociation kinetics indicates the presence of chain heterogeneity. The monomeric form of the protein exhibits mono-exponential time courses in all the experimental situations explored. Although the rate constants associated with the reactions of individual dimer and monomer molecular species are very different, the two species of chiton investigated show remarkably similar properties when compared with each other. All the reactions studied are pH-independent in the range pH 6-8. Amino acid analysis indicates that the monomeric units that combine to form the dimeric species are not identical with the naturally occurring monomeric form. A comparison is made between the chiton myoglobins and other similar O2-binding proteins.
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Affiliation(s)
- S E Smith
- Department of Biochemistry, University of Auckland, New Zealand
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The linkage between oxygenation and subunit association in human hemoglobin Kansas. Concentration dependence of the oxygen binding equilibria. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(19)86327-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Steinmeier RC, Parkhurst LJ. Oxygen and carbon monoxide equilibria and the kinetics of oxygen binding by the cooperative dimeric hemoglobin of Thyonella gemmata. Biochemistry 1979; 18:4645-51. [PMID: 497157 DOI: 10.1021/bi00588a027] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Mills F, Ackers G. Thermodynamic studies on the oxygenation and subunit association of human hemoglobin. Temperature dependence of the linkage between dimer-tetramer association and oxygenation state. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(17)30155-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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BEEK GGM, ZUIDERWEG ERP, BRUIN SH. The Binding of Protons and Inositol Hexakisphosphate to Ligated and Unligated Human Des-Arg141alpha-hemoglobin. ACTA ACUST UNITED AC 1978. [DOI: 10.1111/j.1432-1033.1978.tb12749.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Valdes R, Ackers GK. Self-association of hemoglobin betaSH chains is linked to oxygenation. Proc Natl Acad Sci U S A 1978; 75:311-4. [PMID: 24215 PMCID: PMC411237 DOI: 10.1073/pnas.75.1.311] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Self-association of unliganded beta(SH) chains into tetramers (4 beta(1) [unk] beta(4)) is experimentally found to be energetically less favorable (DeltaG(0) = -19.05 +/- 0.30 kcal) than the corresponding oligomerization of fully oxygenated chains (4 beta(1)X [unk] beta(4)X(4); DeltaG(0) = -22.45 +/- 0.35 kcal). Hence the tetramers must bind oxygen with a higher affinity than that of dissociated chains. Calculations are presented showing why this affinity difference is not easily detected. The linkage is in a direction opposite to that exhibited by normal hemoglobin A, in which oligomerization of high-affinity unliganded dimers (2 alphabeta [unk] alpha(2)beta(2)) leads to tetramers with decreased oxygen affinity. In contrast, the oligomerization of high-affinity, unliganded beta(SH) chains leads to tetramers with even higher affinity. The results imply the existence of at least two conformational states for beta chains. Effects of inositol hexaphosphate on beta chain association were investigated. Inositol hexaphosphate was found to have no measurable effect at pH 7.4, in contrast to pH 7 where very pronounced effects have been observed. Some theoretical aspects of the linkages are presented and the relationship of the findings to concepts of structural transition and allosteric regulation is discussed. In contrast to the beta chains, self-association of alpha chains into dimers was found to occur with the same free energy in both unliganded and fully oxygenated states. Thus, the self-association of alpha chains is not linked to oxygenation.
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Sasaki J, Imamura T, Yanase T. Hemoglobin Hirose, a human hemoglobin variant with a substitution at the alpha1beta2 interface. Subunit dissociation and the equilibria and kinetics of ligand binding. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)38273-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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29
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Raap A, Van Leeuwen JW, Rollema HS, De Bruin SH. Pulse-radiolytic studies on the spin-state transitions in aquomethemoglobin after reduction of a single heme group. FEBS Lett 1977; 81:111-4. [PMID: 902764 DOI: 10.1016/0014-5793(77)80939-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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31
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DeYoung A, Pennelly RR, Tan-Wilson AL, Noble RW. Kinetic studies on the binding affinity of human hemoglobin for the 4th carbon monoxide molecule, L4. J Biol Chem 1976. [DOI: 10.1016/s0021-9258(17)33000-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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32
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Winslow RM, Charache S. Hemoglobin Richmond. Subunit dissociation and oxygen equilibrium properties. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)41022-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Abstract
It is our purpose to review recent experiments on haemoglobin in order to discuss them in terms of the two state model of cooperativity. Excellent previous reviews are available of the chemistry of haemoglobin (Antonini & Brunori, 1971; Gibson, 1959b) which are referred to when possible. The plethora of data necessitates that a selection must be made in a review. An intentionally wide range of experiments is selected to exhibit
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Fung LW, Ho C. A proton nuclear magnetic resonance study of the quaternary structure of human homoglobins in water. Biochemistry 1975; 14:2526-35. [PMID: 1138870 DOI: 10.1021/bi00682a036] [Citation(s) in RCA: 91] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Proton nuclear magnetic resonance spectra of human hemoglobins in water reveal several exchangeable protons which are indicators of the quaternary structures of both the liganded and unliganded molecules. A comparison of the spectra of normal human adult hemoglobin with those of mutant hemoglobins Chesapeake (FG4alpha92 Arg yields Leu), Titusville (G1alpha94 Asp yields Asn), M Milwaukee (E11beta67 Val yields Glu), Malmo (FG4beta97 His yields Gln), Kempsey (G1beta99 Asp yields Asn), Yakima (G1beta99 Asp yields His), and New York (G15beta113 Val yields Glu), as well as with those of chemically modified hemoglobins Des-Arg(alpha141), Des-His(beta146), NES (on Cys-beta93)-Des-Arg(alpha141), and spin-labeled hemoglobin [Cys-beta93 reacted with N-(1-oxyl-2,2,6,6-tetramethyl-4-piperidinyl)iodoacetamide], suggests that the proton in the important hydrogen bond between the tyrosine at C7alpha42 and the aspartic acid at G1beta99, which anchors the alpha1beta2 subunits of deoxyhemoglobin (a characteristic feature of the deoxy quaternary structure), is responsible for the resonance at -9.4 ppm from water at 27 degrees. Another exchangeable proton resonance which occurs at -6.4 ppm from H2O is a spectroscopic indicator of the deoxy structure. A resonance at -5.8 ppm from H2O, which is an indicator of the oxy conformation, is believed to originate from the hydrogen bond between the aspartic acid at G1alpha94 and the asparagine at G4beta102 in the alpha1beta2 subunit interface (a characteristic feature of the oxy quaternary structure). In the spectrum of methemoglobin at pH 6.2 both the -6.4- and the -5.8ppm resonances are present but not the -9.4-ppm resonance. Upon the addition of inositol hexaphosphate to methemoglobin at pH 6.2, the usual resonance at -9.4 ppm is shifted to -10 ppm and the resonance at 6.4 ppm is not observed. In the spectrum of methemoglobin at pH greater than or equal to 7.6 with or without inositol hexaphosphate, the resonance at -5.8 ppm is present, but not those at -10 and -6.4 ppm, suggesting that methemoglobin at high pH has an oxy-like structure. Two resonances (at -8.2 and -7.3 ppm) which remain invariant in the two quaternary structures could come from exchangeable protons in the alpha1beta1 subunit interface and/or other exchangeable protons in the hemoglobin molecule which undergo no conformational changes during the oxygenation process. These exchangeable proton resonances serve as excellent spectroscopic probes of the quaternary structures of the subunit interfaces in studies of the molecular mechanism of cooperative ligand binding to hemoglobin.
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35
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Hensley P, Edelstein SJ, Wharton DC, Gibson QH. Conformation and spin state in methemoglobin. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)41877-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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36
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Ackers GK, Halvorson HR. The linkage between oxygenation and subunit dissociation in human hemoglobin. Proc Natl Acad Sci U S A 1974; 71:4312-6. [PMID: 4530985 PMCID: PMC433872 DOI: 10.1073/pnas.71.11.4312] [Citation(s) in RCA: 81] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The use of subunit dissociation as a means of probing intersubunit contact energy changes which accompany cooperative ligand binding has been studied for the case of human hemoglobin. An analysis is presented delineating the information that can be obtained from the linkage relationships between ligand binding and subunit dissociation of hemoglobin tetramers into dimers. The analysis defines (a) the variation of the saturation function, Y, with total protein concentration, (b) the variation of the subunit dissociation constant (x)K(2) with ligand concentration (X) and (c) the correlations between changes in dimer-dimer contact energy and the sequential ligand binding steps. Sensitivity of the linkage function has been explored by numerical simulation. It is shown that subunit dissociation may appreciably affect oxygenation curves under usual conditions of measurement and that relying solely on either (x)K(2) or Y may lead to incorrect picutres of the energetics, whereas the combination defines the system much more exactly.
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Janssen LH, de Bruin SH. Some aspects of cooperativity in human hemoglobin. Biophys Chem 1973; 1:130-3. [PMID: 4803121 DOI: 10.1016/0301-4622(73)80010-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Abstract
(19)F-Nuclear magnetic resonance studies of specifically fluorinated hemoglobin derivatives have been used to determine the apparent pK(a) of the histidine beta146 imidazole in deoxyhemoglobin. The titration of this residue was found to be abnormally sharp, particularly in the presence of diphosphoglyceric acid. The explanation advanced for this unusual titration curve may have implications for the mechanism of cooperative ligand binding. The possible role of such ionizations is discussed in light of some chemical evidence that the cooperative binding process is governed to a greater extent by internal nonpolar forces than by electrostatic interactions of exposed groups.
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