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External potential modifies memory of solute particles: A particle-viscous bath model. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.117918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Muranyi IS, Otto C, Pickardt C, Osen R, Koehler P, Schweiggert-Weisz U. Influence of the Isolation Method on the Technofunctional Properties of Protein Isolates from Lupinus angustifolius L. J Food Sci 2016; 81:C2656-C2663. [PMID: 27706815 DOI: 10.1111/1750-3841.13515] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/03/2016] [Accepted: 09/03/2016] [Indexed: 11/26/2022]
Abstract
The technofunctional properties of 2 protein isolates from Lupinus angustifolius L. Vitabor isolated by different procedures were investigated. The lupin protein isolate prepared by aqueous alkaline extraction with subsequent isoelectric precipitation (ILP) showed a significantly higher degree of protein denaturation and lower denaturation temperatures than the one obtained by aqueous salt-induced extraction followed by dilutive precipitation (MLP) as determined by differential scanning calorimetry. Rheological investigations revealed higher firmness and a viscoelastic solid-like behavior of ILP, in contrast to MLP that showed viscoelastic, liquid-like properties. Protein solubility of MLP was higher compared to ILP and solubility minima were slightly different for both lupin protein isolates. The protein isolates exhibited different technofunctional properties with ILP showing higher water binding capacity, lower oil binding capacity and lower emulsifying capacity than MLP. This reflects the different putative application of both lupin protein isolates as food ingredients, for example for ILP as a moisture enhancer and for MLP as a "natural" emulsifier in mixed food systems.
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Affiliation(s)
- Isabel S Muranyi
- Fraunhofer Inst. for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354, Freising, Germany
| | - Clemens Otto
- Fraunhofer Inst. for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354, Freising, Germany
| | - Claudia Pickardt
- Fraunhofer Inst. for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354, Freising, Germany
| | - Raffael Osen
- Fraunhofer Inst. for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354, Freising, Germany
| | - Peter Koehler
- German Research Centre for Food Chemistry, Lise-Meitner-Strasse 34, D-85354, Freising, Germany
| | - Ute Schweiggert-Weisz
- Fraunhofer Inst. for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354, Freising, Germany
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Muranyi IS, Volke D, Hoffmann R, Eisner P, Herfellner T, Brunnbauer M, Koehler P, Schweiggert-Weisz U. Protein distribution in lupin protein isolates from Lupinus angustifolius L. prepared by various isolation techniques. Food Chem 2016; 207:6-15. [PMID: 27080873 DOI: 10.1016/j.foodchem.2016.03.073] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Revised: 03/04/2016] [Accepted: 03/21/2016] [Indexed: 10/22/2022]
Abstract
Differences in the protein distribution of various protein isolates from Lupinus angustifolius L. Vitabor were identified as affected by the isolation procedure (alkaline and/or salt-induced extraction followed by isoelectric and/or dilutive precipitation). Protein isolates extracted in alkaline solution showed higher protein yields (26.4-31.7%) compared to salt-induced extraction (19.8-30.0%) or combined alkaline and salt-induced extraction (23.3-25.6%). Chemical variations among the protein isolates especially occurred within the albumins. Protein isolates precipitated isoelectrically showed the highest contents, whereas protein isolates precipitated by dilutive showed the lowest contents of conglutin δ. Furthermore, the alkaline subunits of conglutin α and conglutin γ decreased during alkaline extraction compared to salt-induced extraction. A decrease in protein-bound polar and basic amino acids was shown after protein isolation. In contrast, the amounts of nonpolar, aliphatic, aromatic, hydroxylated and sulfur-rich amino acids were higher in the lupin protein isolates compared to the lupin flakes. However, the functional side chains could not be related to the specific molecular arrangements of the protein isolates, as a similar amino acid composition was found among the protein isolates.
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Affiliation(s)
- Isabel S Muranyi
- Fraunhofer Institute for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354 Freising, Germany.
| | - Daniela Volke
- Center for Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, University Leipzig, Deutscher Platz 5, D-04103 Leipzig, Germany
| | - Ralf Hoffmann
- Center for Biotechnology and Biomedicine, Faculty of Chemistry and Mineralogy, University Leipzig, Deutscher Platz 5, D-04103 Leipzig, Germany
| | - Peter Eisner
- Fraunhofer Institute for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354 Freising, Germany
| | - Thomas Herfellner
- Fraunhofer Institute for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354 Freising, Germany
| | - Markus Brunnbauer
- German Research Centre for Food Chemistry, Lise-Meitner-Strasse 34, D-85354 Freising, Germany
| | - Peter Koehler
- German Research Centre for Food Chemistry, Lise-Meitner-Strasse 34, D-85354 Freising, Germany
| | - Ute Schweiggert-Weisz
- Fraunhofer Institute for Process Engineering and Packaging (IVV), Giggenhauser Strasse 35, D-85354 Freising, Germany
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Microscopic characterisation and composition of proteins from lupin seed (Lupinus angustifolius L.) as affected by the isolation procedure. Food Res Int 2013. [DOI: 10.1016/j.foodres.2013.10.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Masson P, Balny C. Linear and non-linear pressure dependence of enzyme catalytic parameters. Biochim Biophys Acta Gen Subj 2005; 1724:440-50. [PMID: 15951113 DOI: 10.1016/j.bbagen.2005.05.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2005] [Revised: 05/03/2005] [Accepted: 05/04/2005] [Indexed: 11/21/2022]
Abstract
The pressure dependence of enzyme catalytic parameters allows volume changes associated with substrate binding and activation volumes for the chemical steps to be determined. Because catalytic constants are composite parameters, elementary volume change contributions can be calculated from the pressure differentiation of kinetic constants. Linear and non-linear pressure-dependence of single-step enzyme reactions and steady-state catalytic parameters can be observed. Non-linearity can be interpreted either in terms of interdependence between the pressure and other environmental parameters (i.e., temperature, solvent composition, pH), pressure-induced enzyme unfolding, compressibility changes and pressure-induced rate limiting changes. These different situations are illustrated with several examples.
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Affiliation(s)
- Patrick Masson
- Centre de Recherches du Service de Santé des Armées, Département de Toxicologie, Unité d'Enzymologie, BP. 87, 38702 La Tronche cédex, France.
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Cooper A, Johnson CM, Lakey JH, Nöllmann M. Heat does not come in different colours: entropy-enthalpy compensation, free energy windows, quantum confinement, pressure perturbation calorimetry, solvation and the multiple causes of heat capacity effects in biomolecular interactions. Biophys Chem 2001; 93:215-30. [PMID: 11804727 DOI: 10.1016/s0301-4622(01)00222-8] [Citation(s) in RCA: 262] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Modern techniques in microcalorimetry allow us to measure directly the heat changes and associated thermodynamics for biomolecular processes in aqueous solution at reasonable concentrations. All these processes involve changes in solvation/hydration, and it is natural to assume that the heats for these processes should reflect, in some way, such changes in solvation. However, the interpretation of data is still somewhat ambiguous, since different non-covalent interactions may have similar thermodynamic signatures, and analysis is frustrated by large entropy-enthalpy compensation effects. Changes in heat capacity (Delta C(p)) have been related to changes in hydrophobic hydration and non-polar accessible surface areas, but more recent empirical and theoretical work has shown how this need not always be the case. Entropy-enthalpy compensation is a natural consequence of finite Delta C(p) values and, more generally, can arise as a result of quantum confinement effects, multiple weak interactions, and limited free energy windows, giving rise to thermodynamic homeostasis that may be of evolutionary and functional advantage. The new technique of pressure perturbation calorimetry (PPC) has enormous potential here as a means of probing solvation-related volumetric changes in biomolecules at modest pressures, as illustrated with preliminary data for a simple protein-inhibitor complex.
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Affiliation(s)
- A Cooper
- Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK.
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Foguel D, Weber G. Pressure-induced dissociation and denaturation of allophycocyanin at subzero temperatures. J Biol Chem 1995; 270:28759-66. [PMID: 7499398 DOI: 10.1074/jbc.270.48.28759] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The thermodynamics of assembly of the allophycocyanin hexamer was examined employing hydrostatic pressures in the range of 1 bar to 2.4 kbar and temperatures of 20 to -12 degrees C, the latter made possible by the decrease of the freezing point of water under pressure. The existence of two processes, dissociation of the hexamer into dimers, (alpha beta)3-->3 (alpha beta), and dissociation of the alpha beta dimers into monomers, (alpha beta)-->alpha + beta have been recognized previously by changes in the absorbance and fluorescence of the tetrapyrrolic chromophores owing to added ligands. The same changes are observed in the absence of ligands at pressures of under 2.4 kbar and temperatures down to -12 degrees C. On decompression from 2.4 kbar at 0 degrees C, appreciable hysteresis and a persistent loss of 50% in the absorbance at 653 nm is observed. It results from the conformational drift of the isolated subunits and is reduced to 10% when the highest pressure is limited to 1.6 kbar. The thermodynamic parameters of the reaction alpha + beta-->alpha beta can be determined from pressure effects on perchlorate solutions of allophycocyanin, which consist of dimers alone. Their previous knowledge permits estimation, under suitable hypotheses, of the thermodynamic parameters of the reaction 3(alpha beta)-->(alpha beta)3 from the overall pressure effects on the hexamers. Both association reactions have positive enthalpy changes, and the whole hexamer assembly is made possible by the excess entropy.
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Affiliation(s)
- D Foguel
- Department of Biochemistry, School of Chemical Science, University of Illinois, Urbana 61801, USA
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Silva JL, Silveira CF, Correia Júnior A, Pontes L. Dissociation of a native dimer to a molten globule monomer. Effects of pressure and dilution on the association equilibrium of arc repressor. J Mol Biol 1992; 223:545-55. [PMID: 1738163 DOI: 10.1016/0022-2836(92)90669-b] [Citation(s) in RCA: 129] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The monomer-dimer association reaction of Arc repressor was studied by pressure-induced dissociation and by dilution. The dissociation was measured by the decrease (red shift) in the average energy of emission of the tryptophan fluorescence. Pressure dissociation also promoted a decrease in the excited-state lifetime of the single tryptophanyl residue, Trp14. These observations suggest that Trp14 becomes exposed to an aqueous environment following dissociation. The pressure-dissociation curves were concentration dependent, with p1/2 (half-dissociation pressure) shifting to higher pressures as the concentration increased. The dissociation constant (KdO) obtained by extrapolating the pressure-dissociation curves to atmospheric pressure was similar to that determined from the dilution curve (KdO = 30 nM). An anomalous steepness of dissociation in response to dilution was observed, suggesting that conformational changes occur as a result of dissociation of Arc repressor. Binding of bis(8-anilinonaphthalene-1-sulfonate) to Arc repressor was not significantly affected by pressure dissociation, whereas thermal or urea denaturation was accompanied by a dramatic decrease in binding. These results suggest that the conformational changes that follow dissociation induced by pressure are more limited than those following denaturation. The tryptophan anisotropy decreased by about one-half, suggesting the dissociation of a globular dimer to a compact monomer. On the other hand, denaturation by urea promoted an increase in anisotropy, as expected for a random-coil conformation. Dissociated Arc has the hydrodynamic properties of a folded monomer. On the other hand, dissociated Arc has a high degree of exposure of hydrophobic side-chains, and the distribution of conformations is much broader than that in the folded dimer. These features suggest that the dissociated subunit is a molten globule. The subunit interaction was substantially increased by a single amino acid substitution (Pro8----Leu), and the free energy of stabilization amounted to -2.9 kcal/mol. This increased stability suggests that residue 8 is located in the dimer interface and that part of the tertiary and most of the quaternary structure constraints result from the interaction between the intersubunit beta-strands.
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Affiliation(s)
- J L Silva
- Departamento de Bioquimica, Universidade Federal do Rio de Janeiro, Brazil
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Cooper A, Sanders B, Dryden DT. Dynamics of genetically-engineered enzymes: fluorescence and depolarized rayleigh scattering studies of yeast phosphoglycerate kinase. J Mol Liq 1989. [DOI: 10.1016/0167-7322(89)80028-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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