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O'Brien WG, Berka V, Tsai AL, Zhao Z, Lee CC. CD73 and AMPD3 deficiency enhance metabolic performance via erythrocyte ATP that decreases hemoglobin oxygen affinity. Sci Rep 2015; 5:13147. [PMID: 26249166 PMCID: PMC4650700 DOI: 10.1038/srep13147] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 07/22/2015] [Indexed: 12/15/2022] Open
Abstract
Erythrocytes are the key target in 5′-AMP induced hypometabolism. To understand how regulation of endogenous erythrocyte AMP levels modulates systemic metabolism, we generated mice deficient in both CD73 and AMPD3, the key catabolic enzymes for extracellular and intra-erythrocyte AMP, respectively. Under physiological conditions, these mice displayed enhanced capacity for physical activity accompanied by significantly higher food and oxygen consumption, compared to wild type mice. Erythrocytes from Ampd3−/− mice exhibited higher half-saturation pressure of oxygen (p50) and about 3-fold higher levels of ATP and ADP, while they maintained normal 2,3-bisphosphoglycerate (2,3-BPG), methemoglobin levels and intracellular pH. The affinity of mammalian hemoglobin for oxygen is thought to be regulated primarily by 2,3-BPG levels and pH (the Bohr effect). However, our results show that increased endogenous levels of ATP and ADP, but not AMP, directly increase the p50 value of hemoglobin. Additionally, the rise in erythrocyte p50 directly correlates with an enhanced capability of systemic metabolism.
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Affiliation(s)
- William G O'Brien
- Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, Texas, USA 77030
| | - Vladimir Berka
- Division of Hematology, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA 77030
| | - Ah-Lim Tsai
- Division of Hematology, Department of Internal Medicine, University of Texas Health Science Center, Houston, Texas, USA 77030
| | - Zhaoyang Zhao
- Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, Texas, USA 77030
| | - Cheng Chi Lee
- Department of Biochemistry and Molecular Biology, University of Texas Health Science Center, Houston, Texas, USA 77030
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Tabushi I, Nishiya T. Artificial Allosteric System 5. Allosteric Gain, Total Cooperativity and Local Cooperativity as Appropriate Indices for Allosteric Effect. Isr J Chem 2013. [DOI: 10.1002/ijch.198800004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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3
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Kuznetsova NP, Panarin EF, Gudkin LR, Mishaeva RN. Biologically active polymer systems based on hemoglobin. Russ Chem Bull 2013. [DOI: 10.1007/s11172-013-0002-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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4
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Duarte CD, Greferath R, Nicolau C, Lehn JM. myo-Inositol trispyrophosphate: a novel allosteric effector of hemoglobin with high permeation selectivity across the red blood cell plasma membrane. Chembiochem 2011; 11:2543-8. [PMID: 21086482 DOI: 10.1002/cbic.201000499] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
myo-Inositol trispyrophosphate (ITPP), a novel membrane-permeant allosteric effector of hemoglobin (Hb), enhances the regulated oxygen release capacity of red blood cells, thus counteracting the effects of hypoxia in diseases such as cancer and cardiovascular ailments. ITPP-induced shifting of the oxygen-hemoglobin equilibrium curve in red blood cells (RBCs) was inhibited by DIDS and NAP-taurine, indicating that band 3 protein, an anion transporter mainly localized on the RBC membrane, allows ITPP entry into RBCs. The maximum intracellular concentration of ITPP, determined by ion chromatography, was 5.5×10(-3) M, whereas a drop in concentration to the limit of detection was observed in NAP-taurine-treated RBCs. The dissociation constant of ITPP binding to RBC ghosts was found to be 1.72×10(-5) M. All data obtained indicate that ITPP uptake is mediated by band 3 protein and is thus highly tissue-selective towards RBCs, a feature of major importance for its potential therapeutic use.
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Affiliation(s)
- Carolina D Duarte
- Institut de Science et d'Ingénierie Supramoléculaires, Université de Strasbourg, 8 allée Gaspard Monge, 67000 Strasbourg, France
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Abstract
Much of our understanding of human physiology, and of many aspects of pathology, has its antecedents in laboratory and clinical studies of hemoglobin. Over the last century, knowledge of the genetics, functions, and diseases of the hemoglobin proteins has been refined to the molecular level by analyses of their crystallographic structures and by cloning and sequencing of their genes and surrounding DNA. In the last few decades, research has opened up new paradigms for hemoglobin related to processes such as its role in the transport of nitric oxide and the complex developmental control of the alpha-like and beta-like globin gene clusters. It is noteworthy that this recent work has had implications for understanding and treating the prevalent diseases of hemoglobin, especially the use of hydroxyurea to elevate fetal hemoglobin in sickle cell disease. It is likely that current research will also have significant clinical implications, as well as lessons for other aspects of molecular medicine, the origin of which can be largely traced to this research tradition.
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6
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Rose ZB. The enzymology of 2,3-bisphosphoglycerate. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 51:211-53. [PMID: 6255773 DOI: 10.1002/9780470122969.ch5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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7
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Weber RE, Ostojic H, Fago A, Dewilde S, Van Hauwaert ML, Moens L, Monge C. Novel mechanism for high-altitude adaptation in hemoglobin of the Andean frog Telmatobius peruvianus. Am J Physiol Regul Integr Comp Physiol 2002; 283:R1052-60. [PMID: 12376398 DOI: 10.1152/ajpregu.00292.2002] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In contrast to birds and mammals, no information appears to be available on the molecular adaptations for O(2) transport in high-altitude ectothermic vertebrates. We investigated Hb of the aquatic Andean frog Telmatobius peruvianus from 3,800-m altitude as regards isoform differentiation, sensitivity to allosteric cofactors, and primary structures of the alpha- and beta-chains, and we carried out comparative O(2)-binding measurements on Hb of lowland Xenopus laevis. The three T. peruvianus isoHbs show similar functional properties. The high O(2) affinity of the major component results from an almost complete obliteration of chloride sensitivity, which correlates with two alpha-chain modifications: blockage of the NH(2)-terminal residues and replacement by nonpolar Ala of polar residues Ser and Thr found at position alpha131(H14) in human and X. leavis Hbs, respectively. The data indicate adaptive significance of alpha-chain chloride-binding sites in amphibians, in contrast to human Hb where chloride appears mainly to bind in the cavity between the beta-chains. The findings are discussed in relation to other strategies for high-altitude adaptations in amphibians.
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Affiliation(s)
- Roy E Weber
- Department of Zoophysiology, University of Aarhus, 131 C. F. Møllers Alle, DK 8000 Aarhus C, Denmark.
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8
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Metzler DE, Metzler CM, Sauke DJ. How Macromolecules Associate. Biochemistry 2001. [DOI: 10.1016/b978-012492543-4/50010-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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9
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Hull EL, Conover DL, Foster TH. Carbogen-induced changes in rat mammary tumour oxygenation reported by near infrared spectroscopy. Br J Cancer 1999; 79:1709-16. [PMID: 10206281 PMCID: PMC2362819 DOI: 10.1038/sj.bjc.6690272] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We have evaluated the ability of steady-state, radially-resolved, broad-band near infrared diffuse reflectance spectroscopy to measure carbogen-induced changes in haemoglobin oxygen saturation (SO2) and total haemoglobin concentration in a rat R3230 mammary adenocarcinoma model in vivo. Detectable shifts toward higher saturations were evident in all tumours (n = 16) immediately after the onset of carbogen breathing. The SO2 reached a new equilibrium within 1 min and remained approximately constant during 200-300 s of administration. The return to baseline saturation was more gradual when carbogen delivery was stopped. The degree to which carbogen increased SO2 was variable among tumours, with a tendency for tumours with lower initial SO2 to exhibit larger changes. Tumour haemoglobin concentrations at the time of peak enhancement were also variable. In the majority of cases, haemoglobin concentration decreased in response to carbogen, indicating that increased tumour blood volume was not responsible for the observed elevation in SO2. We observed no apparent relationship between the extent of the change in tumour haemoglobin concentration and the magnitude of the change in the saturation. Near infrared diffuse reflectance spectroscopy provides a rapid, non-invasive means of monitoring spatially averaged changes in tumour haemoglobin oxygen saturation induced by oxygen modifiers.
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Affiliation(s)
- E L Hull
- Department of Physics and Astronomy, University of Rochester, NY 14627, USA
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11
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Groebe DR, Busch MR, Tsao TY, Luh FY, Tam MF, Chung AE, Gaskell M, Liebhaber SA, Ho C. High-level production of human alpha- and beta-globins in insect cells. Protein Expr Purif 1992; 3:134-41. [PMID: 1422217 DOI: 10.1016/s1046-5928(05)80097-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
High-level production of human alpha- and beta-globins in cultured Spodoptera frugiperda (Sf-9) cells infected with recombinant baculoviruses is described. The expressed globins are produced to 70-140 mg protein/liter of cell culture or 5-10% of the total cellular protein. Two recombinant baculoviruses for alpha-globin, H alpha and H beta alpha, differ in their construction in that the 5'-untranslated region of the beta-globin gene is inserted 5' to the alpha-globin mRNA coding region in H beta alpha. This insertion results in a 40% increase in yield of alpha-globin over that of H alpha. Consistent with previous observations of the processing of recombinant proteins in Sf-9 cells, both alpha- and beta-globins expressed in Sf-9 cells are correctly processed to remove the initiating methionine from the amino termini of the globins. Sequencing of the expressed globins in Sf-9 cells confirms their identity with globins purified from human normal adult hemoglobin.
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Affiliation(s)
- D R Groebe
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
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13
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Poyart C, Schaad O, Kister J, Galacteros F, Edelstein SJ, Blouquit Y, Arous N. Hemoglobin Saint Mandé [beta 102 (G4) Asn----Tyr]. Functional studies and structural modeling reveal an altered T state. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 194:343-8. [PMID: 2269272 DOI: 10.1111/j.1432-1033.1990.tb15624.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Oxygen equilibrium studies of purified hemoglobin Saint Mandé (Hb SM) [beta 102 (G4) Asn----Tyr] reveal a decreased oxygen affinity and cooperativity but to a lesser extent than found for Hb Kansas (beta 102 Thr). The low affinity of Hb SM depends on environmental conditions: eliminating chloride or raising the pH greatly elevated the ratio of p50 of Hb SM to that of Hb A. The alkaline Bohr effect is reduced by about 40%. The effects of anions (chloride, organophosphates) binding to deoxy Hb SM are also reduced. These data indicate that the functional properties of Hb SM are intermediary between Hb A and Hb Kansas. In addition, molecular graphics modeling of Hb SM in the oxy and deoxy structures indicate the possibility of a new hydrogen bond in the T state between beta(1)102 Tyr and alpha(2)42 Tyr. Stabilisation of the T state in this manner is a plausible explanation for several of the effects observed.
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Affiliation(s)
- C Poyart
- Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine Paris-Sud, France
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14
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Marden MC, Kister J, Poyart C. Fitting abnormal oxygen equilibrium curves of hemoglobin. Biophys Chem 1990; 37:363-9. [PMID: 2149519 DOI: 10.1016/0301-4622(90)88035-q] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A growing number of oxygen equilibrium curves for hemoglobin (Hb) mutants, post-translational modifications, or the binding of potent new effectors of Hb cannot be fitted adequately with the two-state model. Examples are curves showing double maxima in the derivative of the Hill plot, or slopes of less than unity. We present such examples of modified hemoglobins and strong effectors in this study and calculate at which substate level the two-state model differs from the data. Analysis of hemoglobin oxygen equilibrium curves is reconsidered using the two-state model extended to allow variation of the individual substate probabilities. In this way the effect on the equilibrium due to perturbations in energy of each substate can be studied as a diagnostic tool.
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15
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Abstract
High-resolution 1H-NMR spectroscopy has been used to investigate the molecular basis of the Bohr effect in human normal adult hemoglobin in the presence of anions which serve as heterotropic effectors, i.e., Cl-, Pi, and 2,3-diphosphoglycerate. The individual H+ equilibria of 22-26 histidyl residues of hemoglobin in both deoxy and carbonmonoxy forms have been measured under buffer conditions chosen to demonstrate the effects of anion binding. The results indicate that beta 2His residues are binding sites for Cl- and Pi in both deoxy and carbonmonoxy forms, and that the affinity of this site for these anions is greater in the deoxy form. Recently assigned, the resonance of beta 146His does not show evidence of involvement in anion binding. The results also indicate that the binding of 2,3-diphosphoglycerate at the central cavity between the two beta-chains in deoxyhemoglobin involves the beta 2His residues, and that the 2,3-diphosphoglycerate-binding site in carbonmonoxyhemoglobin may remain similar to that in deoxyhemoglobin. The interactions of Cl-, Pi and 2,3-diphosphoglycerate also result in changes in the pK values for other surface histidyl residues which vary in both magnitude and direction. The array of pK changes is specific for the interaction of each effector. The participation of beta 2His in the Bohr effect demonstrates that this residue can release or capture protons, depending on its protonation properties and its linkage to anion binding, and therefore provides an excellent illustration of the variable roles of a given amino acid. Although beta 146His does not bind anions, its contributions to the Bohr effect are substantially affected by the presence of anions. These results demonstrate that long-range electrostatic and/or conformational effects of anions binding play significant roles in the molecular basis of the Bohr effect of hemoglobin.
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Affiliation(s)
- M R Busch
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213
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16
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Pinilla M, Jimeno P, Moreno M, Luque J. Fractionation in two-phase systems of red cells during rat development: changes in pyruvate kinase and bisphosphoglycerate mutase activities in relation to red cell switching. Mol Cell Biochem 1990; 94:37-44. [PMID: 2166231 DOI: 10.1007/bf00223560] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
An inverse relationship between 2,3-bisphosphoglycerate levels and the ratio calculated from pyruvate kinase and bisphosphoglycerate mutase activities has been observed in red populations of rats during animal development. Counter-current distribution in aqueous two-phase systems of these cells populations shows a displacement of distribution profiles towards the high-numbered cavities of the rotor as animal ages. Heterogeneity of cells after distribution is only observed during the switching process from fetal to adult red cells taking place along the postnatal stage of development. Values for the pyruvate kinase/bisphosphoglycerate mutase ratio in these fractions suggest the separation of fetal (liver) from adult (bone marrow) red cells.
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Affiliation(s)
- M Pinilla
- Departamento de Bioquìmica y Biologia Molecular, Universidad de Alcalà de Henares, Madrid, Spain
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17
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Holland RA, Tibben EA, Hallam JF. Interaction between organic phosphates and sheep hemoglobins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1990; 277:191-7. [PMID: 1710868 DOI: 10.1007/978-1-4684-8181-5_24] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Measurements have been made of the effect of the organic phosphate 2,3-DPG and inositol hexaphosphate (IP6) on the OEC of sheep hemoglobins A, B, and F. A thin film method (HEM-O-SCAN) was used and the hemoglobin concentration was about one quarter to one third of that normally found in red cells. All experiments were in bis-tris-saline buffer and in the absence of CO2. At low concentrations of IP6 and at concentrations of 2,3-DPG similar to red cell concentrations, the OEC was right-shifted in all cases, P50 being increased by a factor of 1.58-1.84 by IP6 and by a factor of 1.41-1.59 by 2,3-DPG. The value of Hill n, the index of cooperativity was not generally changed by 2,3-DPG but was decreased by IP6.
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Affiliation(s)
- R A Holland
- School of Physiology and Pharmacology, University of New South Wales, Kensington, Australia
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18
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Berman PA, Black DA, Human L, Harley EH. Oxypurine cycle in human erythrocytes regulated by pH, inorganic phosphate, and oxygen. J Clin Invest 1988; 82:980-6. [PMID: 2458389 PMCID: PMC303611 DOI: 10.1172/jci113707] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The effect of pH, PO2, and inorganic phosphate on the uptake and metabolism of hypoxanthine by erythrocytes has been studied. Uptake of hypoxanthine and accumulation of inosine 5'-monophosphate (IMP) were markedly increased at acid pH, high external phosphate concentrations, and low PO2. Release of accumulated IMP as hypoxanthine occurred at alkaline pH values and low external phosphate concentrations. Conditions favoring IMP accumulation gave rise, in the absence of hypoxanthine, to a corresponding increase in 5'-phosphoribosyl-1-pyrophosphate. Intracellular phosphate concentrations were markedly pH dependent and a model is presented whereby hypoxanthine uptake and release are controlled by intracellular concentrations of inorganic phosphate and 2,3-bisphosphoglycerate. These allosteric effectors influence, in opposing ways, two enzymes governing IMP accumulation, namely 5'-phosphoribosyl-1-pyrophosphate synthetase and 5'-nucleotidase. These metabolic properties suggest that the erythrocyte could play a role in the removal of hypoxanthine from anoxic tissue.
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Affiliation(s)
- P A Berman
- Department of Chemical Pathology, University of Cape Town Medical School, South Africa
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19
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Schmidt W, Maassen N, Trost F, Böning D. Training induced effects on blood volume, erythrocyte turnover and haemoglobin oxygen binding properties. EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY AND OCCUPATIONAL PHYSIOLOGY 1988; 57:490-8. [PMID: 3396563 DOI: 10.1007/bf00417998] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The effect of three weeks ergometer training (Tr) 5 times a week for 45 min at 70% VO2max by 6 subjects on erythrocyte turnover and haemoglobin O2 affinity has been studied. Increased reticulocytosis could be observed from the second day after beginning Tr until a few days after its end, probably caused by increased erythropoietin release by the kidney. Erythrocyte destruction was most pronounced in the first and markedly reduced in the third week of Tr. Elevated glutamate oxalacetate transaminase activity and creatine as well as lowered mean corpuscular haemoglobin indicate a younger erythrocyte population in the first week of recovery. Total blood volume increased during the course of Tr by 700 ml, mainly caused by a raised plasma volume (74%). Red cell volume increased later with maximal values one week after Tr (+280 ml). In this week the standard oxygen dissociation curve was most shifted to the right (P50 increased from 3.77 +/- 0.05 kPa to 3.99 +/- 0.07 kPa) and the Bohr coefficients had their lowest values. Both effects are completely explainable by the haemoglobin O2 binding properties of young erythrocytes. After training, all parameters of physical performance (VO2max, maximal workload, heart rate during rest and exercise) were markedly improved, indicating fast adaptation mechanisms. The increased erythrocyte turnover, including higher erythropoiesis, seems to be one important part of these effects.
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Affiliation(s)
- W Schmidt
- Abteilung für Sport- und Arbeitsphysiologie, Medizinische Hochschule Hannover, Federal Republic of Germany
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Carmona P, Rodriguez ML. Hydrogen bonds between protein side chains and phosphates and their role in biological calcification. Biophys Chem 1987; 28:161-7. [PMID: 2447975 DOI: 10.1016/0301-4622(87)80085-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Poly(L-histidine)-phosphate (H2PO4-, HPO4(2-)) and poly(L-glutamate)-phosphate systems (residue/phosphate, 1:1) in the presence of Ca2+ are studied by infrared spectroscopy. In the poly(L-histidine)-phosphate systems N...HOP in equilibrium NH+...O-P hydrogen bonds are formed where most phosphate protons are found at the histidine ring. With an increase in the degree of hydration the proportion of the proton limiting structure NH+...O-P increases. In the poly(L-glutamate)-dihydrogen phosphate system most phosphate protons are found at the carboxylate groups. Different behavior is observed for poly(L-glutamate)-hydrogen phosphate mixtures, where the residence time of the phosphate proton at the hydrogen acceptor carboxylate group is very short. This residence time increases, however, with increasing humidity. All these results support the triphasic theory of biological calcification involving a tripartite protein-calcium-phosphate complex where these hydrogen bonds can be present. The behavior of these hydrogen bonds can also explain the formation of a nidus of calcium phosphate salts in calcium oxalate-containing urinary calculi.
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Affiliation(s)
- P Carmona
- Instituto de Optica (CSIC), Madrid, Spain
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21
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Kister J, Poyart C, Edelstein SJ. Oxygen-organophosphate linkage in hemoglobin A. The double hump effect. Biophys J 1987; 52:527-35. [PMID: 3676434 PMCID: PMC1330043 DOI: 10.1016/s0006-3495(87)83242-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
At low concentrations of chloride ions, and in the presence of nonsaturating concentrations of organophosphates, the oxygen equilibrium curves (OEC) for solutions of human adult hemoglobin exhibit a biphasic shape conveniently revealed by graphical analysis of the first derivative of the Hill equation with a characteristic form that we call "the double hump effect." This shape, observed for sub-saturating concentrations of organophosphates, stands in marked contrast to the simple lateral shifts of the OEC represented largely by scaling factors when pH or chloride are varied. In the case of protons or chloride, there is a self-buffering effect due to the presence of a large reservoir of proton or chloride binding sites not necessarily linked to oxygen, whereas such sites do not exist in the case of organophosphates. In addition, in the former case, we are dealing with curves measured at constant activity of the effector, while in the latter, at constant concentration. In the presence of saturating concentrations of inositol hexaphosphate (IHP), at low chloride concentration, the entire OEC is shifted to the right, including both its upper and lower asymptotes, indicating a decrease in the intrinsic oxygen affinities of both the T and R states. Theoretical considerations leading to a successful modeling of OEC obtained under nonsaturating and saturating concentrations of IHP required an expanded two-state allosteric model in which IHP-dependent variations in oxygen association constants for both the T and R conformations are taken into account.
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Affiliation(s)
- J Kister
- Institut National de la Santé et de la Recherche Médicale, Hôpital de Bicêtre, Le Kremlin-Bicetre, France
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22
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Kister J, Poyart C, Edelstein SJ. An expanded two-state allosteric model for interactions of human hemoglobin A with nonsaturating concentrations of 2,3-diphosphoglycerate. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)45319-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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23
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Fantl WJ, Di Donato A, Manning JM, Rogers PH, Arnone A. Specifically carboxymethylated hemoglobin as an analogue of carbamino hemoglobin. Solution and X-ray studies of carboxymethylated hemoglobin and X-ray studies of carbamino hemoglobin. J Biol Chem 1987. [DOI: 10.1016/s0021-9258(18)45263-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Schmidt W, Böning D, Braumann KM. Red cell age effects on metabolism and oxygen affinity in humans. RESPIRATION PHYSIOLOGY 1987; 68:215-25. [PMID: 3602618 DOI: 10.1016/s0034-5687(87)80007-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Hemoglobin-oxygen-binding characteristics and essential influencing factors were investigated in human erythrocytes of different age separated by density gradient centrifugation. The most important age-dependent changes of the cell milieu are losses of K+, organic phosphates and water; the latter also leads to an increased concentration of negative charges on Hb. This augments the Donnan effect, which is only partly compensated for by a decrease of DPG-. The oxygen dissociation curve of the oldest fraction (P50 23.4 mm Hg) is shifted to the left compared to young cells (P50 29.2 mm Hg), and Hills 'n' is decreased (old cells 2.31, young cells 2.74). The Bohr effect for CO2 increases in the old population (BCCO2 at 50% SO2 -0.63 and -0.24 for old and young erythrocytes, respectively). This effect is less pronounced for the Bohr coefficients for lactic acid (delta BCLac 0.09). Most cell age-dependent alterations of Hb-O2-binding (including BCCO2) are explainable by opposite alterations of [Hb] and [DPG], causing the change of the ratio [DPG]/[Hb] from 1.3 to 0.7 during the aging process of the erythrocytes. Minor effects may result from aging of the Hb-molecule itself.
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25
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Girard F, Kister J, Bohn B, Poyart C. Functional properties of hemoglobin in human red cells. I. Oxygen equilibrium curves and DPG binding. RESPIRATION PHYSIOLOGY 1987; 68:227-38. [PMID: 3602619 DOI: 10.1016/s0034-5687(87)80008-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Oxygen equilibrium curves (OEC) for human red blood cells (RBC) have revealed a large asymmetry with an nmax value reached at approximately 90% saturation. This contrasts with the symmetrical shape of the OEC for diluted HbA solutions. We prepared resealed red blood cells (RRBC) through controlled hemolysis and resealing in order to obtain a low Hb concentration (approximately equal to 60 g/L) and DPG/Hb4 molar ratio ranging from 0.2 to 4. When the DPG/Hb4 was close to unity, OEC still showed a large asymmetry. On the contrary, the OEC became symmetrical when DPG/Hb4 was either negligible or 3-4 fold the normal value. The asymmetrical OEC for intact RBC can be fitted with a theoretical model taking into account the variations of free DPG concentration during oxygenation. We conclude that the asymmetrical shape of OEC observed in intact fresh RBC is not due to the high protein concentration present in the RBC but to a functional heterogeneity of Hb due to the changes of the free 2,3-diphosphoglycerate (DPG) concentration during oxygenation.
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Roche E, Knecht E, Grisolía S. 2,3-Bisphosphoglycerate protects mitochondrial and cytosolic proteins from proteolytic inactivation. Biochem Biophys Res Commun 1987; 142:680-7. [PMID: 3548716 DOI: 10.1016/0006-291x(87)91468-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
2,3-bisphosphoglycerate at physiological concentration similar to that found in many tissues protects effectively ornithine transcarbamoylase (OTC) from proteolytic inactivation by broken lysosomes. 2,3-bisphosphoglycerate protects also many other mitochondrial and cytosolic proteins, such as glutamate dehydrogenase (GDH) an glyceraldehyde-3-phosphate dehydrogenase (GAPDH), from proteolysis by broken lysosomes and other proteases. It is, thus, suggested that 2,3-bisphosphoglycerate may play an important role in the control of the degradative rates of some proteins, which may explain its high concentration in certain cells.
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Burget U, Zundel G. Proton polarizability and proton transfer in histidine-phosphate hydrogen bonds as a function of cations present: ir investigations. Biopolymers 1987; 26:95-108. [PMID: 3801599 DOI: 10.1002/bip.360260111] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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Carreras J, Bartrons R, Climent F, Cusso R. Bisphosphorylated metabolites of glycerate, glucose, and fructose: functions, metabolism and molecular pathology. Clin Biochem 1986; 19:348-58. [PMID: 3555887 DOI: 10.1016/s0009-9120(86)80008-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
2,3-Bisphosphoglycerate, glucose 1,6-P2 and fructose 2,6-P2 have been recognized as regulatory signals implicated in the control of metabolism, oxygen affinity of red cells and other cellular functions. The alterations of their metabolism constitute a novel area in molecular pathology. The concentration of 2,3-bisphosphoglycerate in erythrocytes changes in a number of pathological conditions. An inherited deficiency of the multifunctional enzyme involved in the synthesis and breakdown of 2,3-bisphosphoglycerate in erythrocytes has been reported. The levels of glucose 1,6-P2 are reduced in the liver and in the muscle of rats with experimentally induced diabetes. In muscle of genetically dystrophic mice a decrease in the levels of glucose 1,6-P2 has been found, probably resulting from enhancement of glucose 1,6-P2 phosphatase activity. Fructose 2,6-P2 levels are decreased in the liver of experimental diabetic mice and rats, and elevated in the liver of genetically obese animals.
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Poillon WN, Kim BC, Welty EV, Walder JA. The effect of 2,3-diphosphoglycerate on the solubility of deoxyhemoglobin S. Arch Biochem Biophys 1986; 249:301-5. [PMID: 3753004 DOI: 10.1016/0003-9861(86)90006-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Although highly charged polyanions, such as inositol hexaphosphate, have been clearly shown to decrease the solubility of deoxyhemoglobin S, the effect of 2,3-diphosphoglycerate (DPG), the endogenous allosteric effector within the red cell, has been more controversial. In this work we have compared the effect of DPG on the solubility of native deoxyhemoglobin S and a derivative in which the DPG binding site is blocked by cross-linking the two beta 82 lysine residues. At pH 6.6 and 30 degrees C the solubility of deoxyhemoglobin S was found to be decreased by 15% (i.e., from 18.8 to 16.0 g/dl) in the presence of saturating concentrations of DPG. Under the same conditions DPG had no effect on the solubility of the cross-linked derivative. This result establishes unequivocally that the binding of DPG within the beta cleft directly facilitates the polymerization of deoxyhemoglobin S. Under physiological conditions, the solubility of deoxyhemoglobin S was found to be decreased by 6% in the presence of an equimolar concentration of DPG. A solubility decrease of this magnitude is sufficient to enhance the tendency of SS cells to sickle and may exacerbate the clinical symptoms of sickle cell disease.
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31
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Benesch RE, Benesch R, Kwong S, McCord JM. Binding of diphosphoglycerate and ATP to oxyhemoglobin dimers. J Mol Biol 1986; 190:481-5. [PMID: 3783709 DOI: 10.1016/0022-2836(86)90016-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The relative affinity of diphosphoglycerate and ATP for hemoglobin dimers and tetramers can be measured under conditions where the protein is in large molar excess over the polyphosphate. Binding of both compounds to dimers was about 25 times stronger than to tetramers in the case of the three low-spin hemoglobins, oxyhemoglobin, carboxyhemoglobin and cyanomethemoglobin. The mutation in hemoglobin Kansas leads to an increased dissociation into alpha beta dimers. The increase in diphosphoglycerate binding by this hemoglobin was in good agreement with that expected from the dimer-tetramer dissociation constant over a wide range of hemoglobin concentrations. In contrast to the liganded hemoglobins, both deoxyhemoglobin and aquomethemoglobin bind the two polyanions as tetramers.
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32
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Burget U, Zundel G. Lysine—phosphate hydrogen bonds and hydrogen-bonded chains with large proton polarizability in polylysine—phosphate systems: ir investigations. J Mol Struct 1986. [DOI: 10.1016/0022-2860(86)87032-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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33
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Arnone A, Rogers PH, Benesch RE, Benesch R, Kwong S. The interaction of folylpolyglutamates with deoxyhemoglobin. Identification of the binding site. J Biol Chem 1986. [DOI: 10.1016/s0021-9258(17)38461-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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34
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Yanagawa S, Hitomi K, Sasaki R, Chiba H. Isolation and characterization of cDNA encoding rabbit reticulocyte 2,3-bisphosphoglycerate synthase. Gene 1986; 44:185-91. [PMID: 3023182 DOI: 10.1016/0378-1119(86)90181-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
We have isolated and sequenced a cDNA clone containing the entire coding region of rabbit reticulocyte 2,3-bisphosphoglycerate (DPG) synthase. The cDNA was verified by translation of the hybridization-selected RNA and by demonstrating identity of the deduced amino acid (aa) sequence to the sequences of CNBr peptides of the purified enzyme. The aa sequence of the enzyme was homologous to the reported sequence of the human enzyme [Haggarty et al., EMBO J. 2 (1983) 1213-1220], especially in the N-terminal half (aa 1-142). Northern blot analysis of rabbit reticulocyte poly(A)+ RNA revealed a single species of mRNA with about 1700 nucleotides.
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35
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Poillon WN, Robinson MD, Kim BC. Deoxygenated sickle hemoglobin. Modulation of its solubility by 2,3-diphosphoglycerate and other allosteric polyanions. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(17)38660-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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36
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Ryall RG, Ellis RH, Wenzel AK. Insensitivity of erythrocyte 2,3-bisphosphoglycerate to changes in extracellular phosphate concentration in vitro. Ann Clin Biochem 1985; 22 ( Pt 3):291-6. [PMID: 3927814 DOI: 10.1177/000456328502200312] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Erythrocytes maintained in vitro under controlled conditions at pH 7.40 were unable to respond to changes in extracellular phosphate concentrations with changes in intracellular 2,3-bisphosphoglycerate content over an 8 h incubation period. Increased extracellular phosphate concentrations did not retard the rate at which 2,3-bisphosphoglycerate concentrations fell when erythrocytes were incubated at pH 7.10. Elevated extracellular phosphate concentrations did not increase the rate of recovery of intracellular 2,3-bisphosphoglycerate concentrations when erythrocytes were returned to pH 7.40 having been incubated at pH 7.10. The rate at which 2,3-bisphosphoglycerate concentrations increased under these latter conditions was too slow to counterbalance any effect that adjustment of blood pH may have on the position of the haemoglobin-oxygen dissociation curve during treatment of diabetic ketoacidosis.
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Bardakjian J, Leclerc L, Blouquit Y, Oules O, Rafaillat D, Arous N, Bohn B, Poyart C, Rosa J, Galacteros F. A new case of hemoglobin Providence (alpha 2 beta 2 82 (EF6) Lys----Asn or Asp) discovered in a French Caucasian family. Structural and functional studies. Hemoglobin 1985; 9:333-48. [PMID: 3935609 DOI: 10.3109/03630268508997009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
A new case of Hb Providence was discovered in a French caucasian family presenting a mild polycythemia. Structural and functional studies of the two abnormal fractions (Hb Providence Asn and Asp) have been performed. These confirm the abnormal characteristics of Hb Providence described previously. Red cells containing Hb Providence were fractionated with a Percoll Albumin density gradient. The respective amounts of the two components were determined in the youngest and oldest cells. We observed a slight increase of Hb Providence Asp from 34 to 37% during the life span of the erythrocytes which confirms that the deamidation of Hb Providence Asn to Hb Providence Asp is a fast process, already present and close to its maximum, in the reticulocytes. Both abnormal components are stable in the presence of isopropanol.
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38
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Wells RM, Weber RE. Fixed acid and carbon dioxide Bohr effects as functions of hemoglobin-oxygen saturation and erythrocyte pH in the blood of the frog, Rana temporaria. Pflugers Arch 1985; 403:7-12. [PMID: 3920641 DOI: 10.1007/bf00583274] [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: 01/08/2023]
Abstract
Using a thin film, dynamic recording technique, the pH sensitivity of the oxygen equilibrium (Bohr effect) of whole blood in the frog Rana temporaria, and its dependence on CO2 and fixed acids and on plasma and erythrocyte pH values were measured. Under standard conditions (20 degrees C, PCO2 = 14.7 mm Hg, pH = 7.65) the oxygen equilibrium could be described by a P50 value of 38 mm Hg and n50 of 1.8 Hill plots of the oxygen equilibria showed increased cooperativity in oxygen binding with increasing saturation (n20 congruent to 1.2, n80 congruent to 4.0). Values of fixed acid and CO2 Bohr factors (phi AH and phi CO2, respectively) were similar at specific saturations (S20, 50, 80) but showed saturation dependence with high values occurring at high saturation. The same statements also hold for the intracellular Bohr factors (derived from the relation between blood P50 and erythrocyte pH) although the values of both phi AH and phi CO2 now were greater than those related to blood pH.
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39
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Docherty JC, Brown SB. Haem degradation in human haemoglobin in vitro. Separation of the contribution of the alpha- and beta-subunits. Biochem J 1984; 222:401-6. [PMID: 6477522 PMCID: PMC1144192 DOI: 10.1042/bj2220401] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Human haemoglobin was prepared containing [14C]haem in either the alpha- or the beta-subunits. Coupled oxidation of such hybrid haemoglobins with ascorbate and O2 showed that the biliverdin produced by the alpha-subunits contained approx. 55% alpha-isomer and 45% beta-isomer, whereas that produced by the beta-subunits contained approx. 75% alpha-isomer and 25% beta-isomer. Coupled oxidation of isolated alpha- and beta-subunits gave approx. 70% alpha-isomer, 30% beta-isomer and 78% alpha-isomer, 22% beta-isomer respectively. These results are consistent with calculations of differences in the haem environment in the two subunit types.
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40
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The interaction of hemoglobin with the cytoplasmic domain of band 3 of the human erythrocyte membrane. J Biol Chem 1984. [DOI: 10.1016/s0021-9258(18)90956-7] [Citation(s) in RCA: 228] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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41
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Rochette J, Varet B, Boissel JP, Clough K, Labie D, Wajcman H, Bohn B, Magne P, Poyart C. Structure and function of Hb Saint-Jacques (α2β2 140 (H18) Ala → Thr): A new high-oxygen-affinity variant with altered bisphosphoglycerate binding. ACTA ACUST UNITED AC 1984; 785:14-21. [PMID: 6546525 DOI: 10.1016/0167-4838(84)90228-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A low P50 value in a fresh red blood cell suspension was discovered in a polycythemic patient (Hb 19 g X dl-1). Routine acid and alkaline electrophoreses of the hemolysate were identical to normal hemolysate. Isoelectrofocusing (pH gradient 6-8) did not reveal any abnormal band whether performed with the fully liganded or deoxygenated samples. Precise analyses of the oxygen dissociation curves of the propositus' red cells demonstrated a biphasic Hill plot, a normal Bohr effect and low interaction with 2,3-bisphosphoglycerate (2,3-DPG). Studies on the unfractionated hemolysate confirmed these observations and the inhibition of the effect of organic phosphates. Structural studies were carried out on the mixture of beta A + beta X chains and revealed the presence of two beta Tp14 peptides. Sequencing the abnormal beta Tp14 peptide showed the substitution Ala----Thr of the beta 140 (H18) residue. This new variant was named Hb Saint-Jacques. Examination of the three dimensional model of HbAo indicates that the substitution beta 140 (H18) Ala----Thr induces van der Waals interactions with the nearby lysine-82 (EF6) and leucine-81 (EF5) and a displacement of the EF corner of the beta chains. This is likely to change the normal position of the lysine-82 (EF6), a major anionic binding site in the central cavity between the two beta chains. Functional studies confirm the interpretation of a steric hindrance inhibiting the binding of large organic phosphates to Hb Saint-Jacques.
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Abstract
Vanadium is distributed extensively in nature. It is a trace element and is present in almost all living organisms including man. Even though vanadium was originally recognized for its ability to inhibit membrane Na+-K+-ATPase, various laboratory studies now document that this element has the capacity to affect the activity of various intracellular enzyme systems and may modify their physiological functions. Vanadium may be an essential element for normal development and may play an important role in various homeostatic mechanisms, and thus vanadium deficiency may prove to be an important concern. Abnormalities in biological disposition of vanadium may be involved in the pathogenesis of certain neurological disorders or cardiovascular diseases. While the essentiality of this element for living organisms is yet to be established with certainty, vanadium has become an increasingly important element and is used extensively in various heavy industries such as steel, oil, etc.; thus, the incidence of exposure to toxic levels of vanadium to industrial workers has been an increasing concern for toxicologists. To date, little information is available on the physiological or pharmacological actions of vanadium; hence, it is difficult to reach any definitive conclusion concerning its biological significance, essentiality and its role in pathological states. An attempt has been made in this review to broadly document what is known of various biological actions of vanadium.
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Benesch RE, Benesch R, Kwong S, Baugh CM. A pteroylpolyglutamate binds to tetramers in deoxyhemoglobin but to dimers in oxyhemoglobin. Proc Natl Acad Sci U S A 1983; 80:6202-5. [PMID: 6578504 PMCID: PMC394263 DOI: 10.1073/pnas.80.20.6202] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The binding of a physiological concentration of pteroylhepta(glutamate) to oxy- and deoxyhemoglobin in large excess was measured by ultrafiltration. The variation of free to bound folate with hemoglobin concentration showed that a single molecule of the pteroylpolyglutamate is bound by deoxyhemoglobin tetramers and by alpha beta dimers in oxyhemoglobin. Although the binding sites are different, the affinity constants are the same and very similar to the 2,3-bisphosphoglycerate binding energy. Nevertheless, in view of the small proportion of dimers in oxyhemoglobin much more pteroylhepta(glutamate) is bound by deoxyhemoglobin over a wide range of hemoglobin concentrations. Because even 2% deoxyhemoglobin is enough to bind all of the erythrocyte folate as polyglutamate, the bulk of it will be bound at physiological oxygen pressures. Free folate could only be expected in fully oxygenated erythrocytes. Therefore, the reaction of pteroylpolyglutamates with hemoglobin represents an oxygenation-dependent storage mechanism that can account for the 40-fold excess of the vitamin in the erythrocyte over the amounts in the serum. Because methotrexate is also converted to polyglutamate derivatives in the erythrocyte, this drug is likely to be concentrated and stored there by the same mechanism.
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Thillet J, Chu AH, Romeo P, Tsapis A, Ackers GK. Effects of anions on the ligand-linked subunit assembly of human hemoglobin: the mutual effects of Cl- and EDTA. Hemoglobin 1983; 7:141-57. [PMID: 6423574 DOI: 10.3109/03630268309048643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We have studied the mutual effects of chloride ion and EDTA on the dimer-tetramer assembly of human deoxyhemoglobin and oxyhemoglobin. It is found that these two anions have similar but interdependent effects. In low C1- (.01 M) increasing concentrations of EDTA are found to decrease both forward and reverse rate constants for deoxyhemoglobin, whereas no effect is observed at 0.1 M C1-. These results suggest that binding of anions at the alpha 1 beta 2 intersubunit contact may stabilize both the dimeric and tetrameric forms of the deoxy molecule, thus inhibiting both the dissociation and reassociation reactions. The overall effects of EDTA and low C1- on the dimer-tetramer equilibrium constants are found to be distinctly different in deoxy and oxyhemoglobins with a major effect on the oxy form. These findings establish validity of the results from previous thermodynamic studies carried out in approximately physiological C1- concentrations along with the small amounts of EDTA which are used to minimize artifacts of oxidation. As observed for deoxyhemoglobin, it is found that in 0.1 M C1- ion there is no further effect of EDTA on the oxyhemoglobin dimer-tetramer equilibrium.
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Abstract
2,3-Bisphosphoglycerate accumulates in mammalian erythrocytes, where it facilitates the supply of oxygen to the tissues by binding to hemoglobin. Regulatory properties of 2,3-bisphosphoglycerate synthase and phosphatase are discussed. The 2,3-bisphosphoglycerate concentration was shown to rise linearly along with the hemoglobin level during erythroid differentiation. The accumulation of 2,3-bisphosphoglycerate was primarily attributable to an increase in 2,3-bisphosphoglycerate synthase. Antibody-binding studies showed that the increased activity is achieved solely through an increase in the amount of enzyme. It was shown that 2,3-bisphosphoglycerate synthase was synthesized in nucleated erythroid precursor cells and also in anucleated reticulocytes. The mRNA of this protein appears to be fairly stable in reticulocytes. Coordinate expression of hemoglobin and 2,3-bisphosphoglycerate synthase was found during dimethylsulfoxide-induced differentiation of Friend erythroleukemia cells. 2,3-Bisphosphoglycerate rose concomitantly.
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Imaizumi K, Imai K, Tyuma I. Linkage between carbon dioxide binding and four-step oxygen binding to hemoglobin. J Mol Biol 1982; 159:703-19. [PMID: 6815332 DOI: 10.1016/0022-2836(82)90109-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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48
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Ackers GK, Benesch RE, Edalji R. Effects of inositol hexasulfate on the oxygen affinity of hemoglobin: verification of the integral function theory of thermodynamic linkage. Biochemistry 1982; 21:875-9. [PMID: 7074057 DOI: 10.1021/bi00534a010] [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: 01/23/2023]
Abstract
A detailed series of experimental measurements have been carried out to investigate the effects of inositol hexasulfate (IHS) on the oxygen binding curves of human hemoglobin. The data provide a critical test of the integral function theory for the mutual interaction of two ligands binding to a nondissociating macromolecule [Ackers, G. K. (1979) Biochemistry 18, 3372-3380]. This theory, which is required for cases where the fractions of bound and unbound ligands are of comparable magnitude, was found to predict quantitatively the observed effects. The experimentally determined variation of the median oxygen concentration with IHS concentration was analyzed by least-squares methods to determine the IHS binding constants for unliganded and fully oxygenated hemoglobin. The derived constants are in good agreement with independent estimates of their values, providing further verification of the theoretical treatment. General aspects of the integral function approach to thermodynamic linkage are briefly outlined. The importance of this approach for treating physiological situations is discussed.
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Benesch R, Benesch R, Kwong S, Acharya A, Manning J. Labeling of hemoglobin with pyridoxal phosphate. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)68194-9] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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50
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Horiuchi K. Some characteristics of beta-naphthyl oligophosphates as allosteric effectors of human hemoglobin. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1982; 14:601-8. [PMID: 7106359 DOI: 10.1016/0020-711x(82)90043-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
1. Fluorescent organic phosphates. beta-naphthyl oligophosphates, were found to interact with human hemoglobin, and to lower the oxygen affinity. The magnitude of the allosteric effect depended on the number of phosphoric groups in each compound. 2. In analogy with inositol hexaphosphate (IHP). beta-naphthyl tetraphosphate (beta-NapP4) was found to interact with oxyhemoglobin. Therefore, the spectral changes in oxyhemoglobin and carboxyhemoglobin induced by beta-NapP4 and IHP were compared. 3. The extent of spectral changes in oxyhemoglobin induced by beta-NapP4 was smaller than that induced by IHP, whereas the extent of spectral changes in carboxyhemoglobin induced by beta-NapP4 was about twice that by IHP. 4. These results indicate that there is a structural difference between oxyhemoglobin and carboxyhemoglobin.
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