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Nattich-Rak M, Pomorska A, Batys P, Adamczyk Z. Adsorption kinetic of myoglobin on mica and silica - Role of electrostatic interactions. Colloids Surf B Biointerfaces 2020; 198:111436. [PMID: 33234411 DOI: 10.1016/j.colsurfb.2020.111436] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/08/2020] [Accepted: 10/20/2020] [Indexed: 01/25/2023]
Abstract
Adsorption kinetics of myoglobin molecules on mica and silica was studied using the atomic force microscopy (AFM), the colloid enhancement and the quartz microbalance (QCM) methods. Measurements were carried out for the NaCl concentration of 0.01 and 0.15 M as a function of pH comprising pH 7.4 stabilized by the PBS buffer. The electrophoretic mobility measurements enabled to derive the molecules zeta potential as a function of pH. The isoelectric point appearing at pH 5, is lower than that predicted from the theoretical calculations of the nominal dissociation charge. The AFM investigations confirmed that myoglobin molecules irreversibly adsorb at pH 3.5 yielding well-defined layers of single molecules. These layers were characterized using the colloid enhancement method involving polymer microparticles for pH range 3-9. The microparticle deposition kinetics was adequately interpreted in terms of a hybrid random sequential adsorption model. It is confirmed that the myoglobin layers exhibit a negligible zeta potential at pH equal to 5 in accordance with the electrophoretic mobility measurements. Analogous adsorption kinetic measurements were performed for the silica substrate using QCM and AFM. It is observed that myoglobin molecules irreversibly adsorb at pH 3.5 forming stable layers of single molecules. On the other hand, its adsorption kinetics at larger pHs was much slower exhibiting a poorly defined maximum coverage. This was attributed to aggregation of the myoglobin solutions due to their vanishing charge. The kinetic QCM runs were adequately interpreted in terms of a theoretical model combining the Smoluchowski aggregation theory with the convective diffusion mass transfer theory.
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Affiliation(s)
- Małgorzata Nattich-Rak
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Science, Niezapominajek 8, 30-239, Cracow, Poland.
| | - Agata Pomorska
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Science, Niezapominajek 8, 30-239, Cracow, Poland
| | - Piotr Batys
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Science, Niezapominajek 8, 30-239, Cracow, Poland
| | - Zbigniew Adamczyk
- Jerzy Haber Institute of Catalysis and Surface Chemistry Polish Academy of Science, Niezapominajek 8, 30-239, Cracow, Poland.
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Haouz A, Glandieres JM, Zentz C, Pin S, Ramstein J, Tauc P, Brochon JC, Alpert B. Solvent effects on horse apomyoglobin dynamics. Biochemistry 1998; 37:3013-9. [PMID: 9485453 DOI: 10.1021/bi972236u] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The effects of the solvent conditions (buffer pH 9, 8, or 7 or buffer pH 6.5 alone or mixed with 3.2% ethanol or 6.2% formamide) on the protein dynamics of horse apomyoglobin were investigated through tryptophan fluorescence quenching, spectra, and decay properties. Raising the pH (which induces discontinuous protein conformation changes) increases the structural fluctuations inside the hydrophobic A, G, and H helix core. Mixed solutions containing either 3.2% ethanol or 6.2% formamide (which redistribute water molecules on the protein surface) produce protein dynamics changes in the vicinity of the two Trp residues, without inducing particular constraints on these very residues. Formamide increases, in the same way, the polarity and the protein flexibility while ethanol reduces both. The present fluorescence work also shows that, whatever the outside solvent, the two Trp residues W7 and W14, embedded in the A, G, and H helix core, are equally and statistically reached by small molecules diffusing inside the protein matrix. Hydrogen-tritium exchange measurements on the protein in mixed solvents reveal that the dynamics of the A, G, and H helix cluster and of the B and E helixes are greatly influenced by the nature of the outside medium. A small amount of formamide in the buffer increases the protein fluctuations while an ethanol-water mixture reduces them. We suggest that the hydratation state of the protein surface could be the relevant parameter of the protein dynamics.
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Affiliation(s)
- A Haouz
- Laboratoire de Biologie Physico-Chimique, Universite Denis Diderot, 2 place Jussieu, 75251 Paris Cedex 05, France
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Sire O, Zentz C, Pin S, Chinsky L, Turpin PY, Martel P, Wong PTT, Alpert B. Long-Range Effects in Liganded Hemoglobin Investigated by Neutron and UV Raman Scattering, FTIR, and CD Spectroscopies. J Am Chem Soc 1997. [DOI: 10.1021/ja9703786] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Olivier Sire
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Christian Zentz
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Serge Pin
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Laurent Chinsky
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Pierre-Yves Turpin
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Pierre Martel
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Patrick T. T. Wong
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
| | - Bernard Alpert
- Contribution from the Laboratoire de Biologie Physico-Chimique, Université Paris 7, 2 place Jussieu, 75251 Paris cedex 05, France, Laboratoire de Physico-Chimie Biomoléculaire et Cellulaire, CNRS UA 2056, Université Paris 6, 4 place Jussieu, 75252 Paris cedex 05, France, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, Ontario K0J 1J0, Canada, and University of Ottawa, Faculty of Medicine, 451 Smyth, Ottawa, Ontario K1H 8M5, Canada
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