1
|
Rai S, Pramanik S, Mukherjee S. Deciphering the liquid-liquid phase separation induced modulation in the structure, dynamics, and enzymatic activity of an ordered protein β-lactoglobulin. Chem Sci 2024; 15:3936-3948. [PMID: 38487243 PMCID: PMC10935713 DOI: 10.1039/d3sc06802a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Accepted: 01/23/2024] [Indexed: 03/17/2024] Open
Abstract
Owing to the significant role in the subcellular organization of biomolecules, physiology, and the realm of biomimetic materials, studies related to biomolecular condensates formed through liquid-liquid phase separation (LLPS) have emerged as a growing area of research. Despite valuable contributions of prior research, there is untapped potential in exploring the influence of phase separation on the conformational dynamics and enzymatic activities of native proteins. Herein, we investigate the LLPS of β-lactoglobulin (β-LG), a non-intrinsically disordered protein, under crowded conditions. In-depth characterization through spectroscopic and microscopic techniques revealed the formation of dynamic liquid-like droplets, distinct from protein aggregates, driven by hydrophobic interactions. Our analyses revealed that phase separation can alter structural flexibility and photophysical properties. Importantly, the phase-separated β-LG exhibited efficient enzymatic activity as an esterase; a characteristic seemingly exclusive to β-LG droplets. The droplets acted as robust catalytic crucibles, providing an ideal environment for efficient ester hydrolysis. Further investigation into the catalytic mechanism suggested the involvement of specific amino acid residues, rather than general acid or base catalysis. Also, the alteration in conformational distribution caused by phase separation unveils the latent functionality. Our study delineates the understanding of protein phase separation and insights into the diverse catalytic strategies employed by proteins. It opens exciting possibilities for designing functional artificial compartments based on phase-separated biomolecules.
Collapse
Affiliation(s)
- Saurabh Rai
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal Bypass Road Bhopal 462066 Madhya Pradesh India
| | - Srikrishna Pramanik
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal Bypass Road Bhopal 462066 Madhya Pradesh India
| | - Saptarshi Mukherjee
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal Bypass Road Bhopal 462066 Madhya Pradesh India
| |
Collapse
|
2
|
Xu D, Zhou J, Soon WL, Kutzli I, Molière A, Diedrich S, Radiom M, Handschin S, Li B, Li L, Sturla SJ, Ewald CY, Mezzenga R. Food amyloid fibrils are safe nutrition ingredients based on in-vitro and in-vivo assessment. Nat Commun 2023; 14:6806. [PMID: 37884488 PMCID: PMC10603083 DOI: 10.1038/s41467-023-42486-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 10/12/2023] [Indexed: 10/28/2023] Open
Abstract
Food protein amyloid fibrils have superior technological, nutritional, sensorial, and physical properties compared to native monomers, but there is as yet insufficient understanding of their digestive fate and safety for wide consumption. By combining SDS-PAGE, ELISA, fluorescence, AFM, MALDI-MS, CD, microfluidics, and SAXS techniques for the characterization of β-lactoglobulin and lysozyme amyloid fibrils subjected to in-vitro gastrointestinal digestion, here we show that either no noticeable conformational differences exist between amyloid aggregates and their monomer counterparts after the gastrointestinal digestion process (as in β-lactoglobulin), or that amyloid fibrils are digested significantly better than monomers (as in lysozyme). Moreover, in-vitro exposure of human cell lines and in-vivo studies with C. elegans and mouse models, indicate that the digested fibrils present no observable cytotoxicity, physiological abnormalities in health-span, nor accumulation of fibril-induced plaques in brain nor other organs. These extensive in-vitro and in-vivo studies together suggest that the digested food amyloids are at least equally as safe as those obtained from the digestion of corresponding native monomers, pointing to food amyloid fibrils as potential ingredients for human nutrition.
Collapse
Affiliation(s)
- Dan Xu
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Plant Protein Deep Processing, Ministry of Education, South China University of Technology, 381 Wushan Road, Tianhe District, Guangzhou, 510640, China
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland
| | - Jiangtao Zhou
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland.
| | - Wei Long Soon
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland
- Center for Sustainable Materials (SusMat), School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Ines Kutzli
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland
| | - Adrian Molière
- Institute of Translational Medicine, Department of Health Sciences and Technology (HEST), ETH Zurich, Schwerzenbach, Switzerland
| | - Sabine Diedrich
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland
| | - Milad Radiom
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland
- Laboratory of Food Immunology, Institute of Food, Nutrition and Health, ETH Zürich, Zürich, Switzerland
| | - Stephan Handschin
- Scientific Center for Optical and Electron Microscopy (ScopeM), ETH Zurich, Otto-Stern-Weg 3, 8093, Zurich, Switzerland
| | - Bing Li
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Plant Protein Deep Processing, Ministry of Education, South China University of Technology, 381 Wushan Road, Tianhe District, Guangzhou, 510640, China
| | - Lin Li
- School of Food Science and Engineering, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Engineering Research Center of Starch and Plant Protein Deep Processing, Ministry of Education, South China University of Technology, 381 Wushan Road, Tianhe District, Guangzhou, 510640, China
| | - Shana J Sturla
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland
| | - Collin Y Ewald
- Institute of Translational Medicine, Department of Health Sciences and Technology (HEST), ETH Zurich, Schwerzenbach, Switzerland
| | - Raffaele Mezzenga
- Institute of Food, Nutrition and Health (IFNH), Department of Health Sciences and Technology (HEST), ETH Zurich, Zürich, 8092, Switzerland.
- Department of Materials, ETH Zurich, Zürich, 8092, Switzerland.
| |
Collapse
|
3
|
O’Donohue M, Saharia J, Bandara N, Alexandrakis G, Kim MJ. Use of a solid-state nanopore for profiling the transferrin receptor protein and distinguishing between transferrin receptor and its ligand protein. Electrophoresis 2023; 44:349-359. [PMID: 36401829 PMCID: PMC9839655 DOI: 10.1002/elps.202200147] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/20/2022] [Accepted: 11/17/2022] [Indexed: 11/20/2022]
Abstract
A nanopore device is capable of providing single-molecule level information of an analyte as they translocate through the sensing aperture-a nanometer-sized through-hole-under the influence of an applied electric field. In this study, a silicon nitride (Six Ny )-based nanopore was used to characterize the human serum transferrin receptor protein (TfR) under various applied voltages. The presence of dimeric forms of TfR was found to decrease exponentially as the applied electric field increased. Further analysis of monomeric TfR also revealed that its unfolding behaviors were positively dependent on the applied voltage. Furthermore, a comparison between the data of monomeric TfR and its ligand protein, human serum transferrin (hSTf), showed that these two protein populations, despite their nearly identical molecular weights, could be distinguished from each other by means of a solid-state nanopore (SSN). Lastly, the excluded volumes of TfR were experimentally determined at each voltage and were found to be within error of their theoretical values. The results herein demonstrate the successful application of an SSN for accurately classifying monomeric and dimeric molecules while the two populations coexist in a heterogeneous mixture.
Collapse
Affiliation(s)
- Matthew O’Donohue
- Applied Science Program, Southern Methodist University, Dallas, TX 75275, USA
| | - Jugal Saharia
- Department of Mechanical Engineering, Southern Methodist University, Dallas, TX 75275, USA
| | - Nuwan Bandara
- Department of Mechanical Engineering, Southern Methodist University, Dallas, TX 75275, USA
| | - Georgios Alexandrakis
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX 76019, USA
| | - Min Jun Kim
- Applied Science Program, Southern Methodist University, Dallas, TX 75275, USA
- Department of Mechanical Engineering, Southern Methodist University, Dallas, TX 75275, USA
| |
Collapse
|
4
|
Uttinger MJ, Hundschell CS, Lautenbach V, Pusara S, Bäther S, Heyn TR, Keppler JK, Wenzel W, Walter J, Kozlowska M, Wagemans AM, Peukert W. Determination of specific and non-specific protein-protein interactions for beta-lactoglobulin by analytical ultracentrifugation and membrane osmometry experiments. SOFT MATTER 2022; 18:6739-6756. [PMID: 36040122 DOI: 10.1039/d2sm00908k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Protein-protein interactions are essential for the understanding of biological processes. Specific protein aggregation is an important aspect for many biological systems. In particular, electrostatic interactions play the key role for protein-protein interactions, as many amino acids have pH-dependent charge states. Moreover, protein dissociation is directly related to the solution pH, ionic strength, temperature and protein concentration. The subtle interplay between different specific and non-specific interactions is demonstrated for beta-lactoglobulin (BLG) with a focus on low salt concentrations, thus mimicking technically relevant processing conditions. BLG is a well-characterized model system, proven to attain its monomer-dimer equilibrium strongly dependent upon the pH of the solution. In this manuscript, we present a unique combination of analytical ultracentrifugation and membrane osmometry experiments, which quantifies specific and non-specific interactions, i.e. in terms of the dimer dissociation constants and the second osmotic virial coefficient, at pH 3 and 7 and sodium chloride concentrations of 10 mM and 100 mM. This provides direct insight to protein-protein interactions for a system with a concentration-dependent monomer-dimer equilibrium. Moreover, using a coarse-grained extended DLVO model in combination with molecular dynamics simulations, we quantify non-specific monomer-monomer, monomer-dimer and dimer-dimer interactions as well as the binding free energy of BLG dimerization from theoretical calculations. The experimentally determined interactions are shown to be mainly governed by electrostatic interactions and further agree with free energy calculations. Our experimental protocol aims to determine non-specific and specific interactions for a dynamically interacting system and provides an understanding of protein-protein interactions for BLG at low salt concentrations.
Collapse
Affiliation(s)
- M J Uttinger
- Institute of Particle Technology, Interdisciplinary Center for Functional Particle Systems, Friedrich-Alexander-Universität Erlangen-Nürnberg, Haberstraße 9a, 91058 Erlangen, Germany.
| | - C S Hundschell
- Institute of Food Technology and Food Chemistry, Department of Food Colloids, Technical University Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - V Lautenbach
- Institute of Particle Technology, Interdisciplinary Center for Functional Particle Systems, Friedrich-Alexander-Universität Erlangen-Nürnberg, Haberstraße 9a, 91058 Erlangen, Germany.
| | - S Pusara
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - S Bäther
- Institute of Food Technology and Food Chemistry, Department of Food Colloids, Technical University Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - T R Heyn
- Institute of Human Nutrition and Food Science, Division of Food Technology, Kiel University, 24118 Kiel, Germany
| | - J K Keppler
- Laboratory of Food Process Engineering, Wageningen University, Wageningen, The Netherlands
| | - W Wenzel
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - J Walter
- Institute of Particle Technology, Interdisciplinary Center for Functional Particle Systems, Friedrich-Alexander-Universität Erlangen-Nürnberg, Haberstraße 9a, 91058 Erlangen, Germany.
| | - M Kozlowska
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - A M Wagemans
- Institute of Food Technology and Food Chemistry, Department of Food Colloids, Technical University Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany
| | - W Peukert
- Institute of Particle Technology, Interdisciplinary Center for Functional Particle Systems, Friedrich-Alexander-Universität Erlangen-Nürnberg, Haberstraße 9a, 91058 Erlangen, Germany.
| |
Collapse
|
5
|
Shibata K, Nakasone Y, Terazima M. Salt effect on the selective photoinduced dimerization of a BLUF domain of EB1. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
6
|
Effects of Monovalent Salt on Protein-Protein Interactions of Dilute and Concentrated Monoclonal Antibody Formulations. Antibodies (Basel) 2022; 11:antib11020024. [PMID: 35466277 PMCID: PMC9036246 DOI: 10.3390/antib11020024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 03/17/2022] [Accepted: 03/24/2022] [Indexed: 02/04/2023] Open
Abstract
In this study, we used sodium chloride (NaCl) to extensively modulate non-specific protein-protein interactions (PPI) of a humanized anti-streptavidin monoclonal antibody class 2 molecule (ASA-IgG2). The changes in PPI with varying NaCl (CNaCl) and monoclonal antibody (mAb) concentration (CmAb) were assessed using the diffusion interaction parameter kD and second virial coefficient B22 measured from solutions with low to moderate CmAb. The effective structure factor S(q)eff measured from concentrated mAb solutions using small-angle X-ray and neutron scattering (SAXS/SANS) was also used to characterize the PPI. Our results found that the nature of net PPI changed not only with CNaCl, but also with increasing CmAb. As a result, parameters measured from dilute and concentrated mAb samples could lead to different predictions on the stability of mAb formulations. We also compared experimentally determined viscosity results with those predicted from interaction parameters, including kD and S(q)eff. The lack of a clear correlation between interaction parameters and measured viscosity values indicates that the relationship between viscosity and PPI is concentration-dependent. Collectively, the behavior of flexible mAb molecules in concentrated solutions may not be correctly predicted using models where proteins are considered to be uniform colloid particles defined by parameters derived from low CmAb.
Collapse
|
7
|
da Rocha L, Baptista AM, Campos SRR. Approach to Study pH-Dependent Protein Association Using Constant-pH Molecular Dynamics: Application to the Dimerization of β-Lactoglobulin. J Chem Theory Comput 2022; 18:1982-2001. [PMID: 35171602 PMCID: PMC9775224 DOI: 10.1021/acs.jctc.1c01187] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Protein-protein association is often mediated by electrostatic interactions and modulated by pH. However, experimental and computational studies have often overlooked the effect of association on the protonation state of the protein. In this work, we present a methodological approach based on constant-pH molecular dynamics (MD), which aims to provide a detailed description of a pH-dependent protein-protein association, and apply it to the dimerization of β-lactoglobulin (BLG). A selection of analyses is performed using the data generated by constant-pH MD simulations of monomeric and dimeric forms of bovine BLG, in the pH range 3-8. First, we estimate free energies of dimerization using a computationally inexpensive approach based on the Wyman-Tanford linkage theory, calculated in a new way through the use of thermodynamically based splines. The individual free energy contribution of each titratable site is also calculated, allowing for identification of relevant residues. Second, the correlations between the proton occupancies of pairs of sites are calculated (using the Pearson coefficient), and extensive networks of correlated sites are observed at acidic pH values, sometimes involving distant pairs. In general, strongly correlated sites are also slow proton exchangers and contribute significantly to the pH-dependency of the dimerization free energy. Third, we use ionic density as a fingerprint of protein charge distribution and observe electrostatic complementarity between the monomer faces that form the dimer interface, more markedly at the isoionic point (where maximum dimerization occurs) than at other pH values, which might contribute to guide the association. Finally, the pH-dependent dimerization modes are inspected using PCA, among other analyses, and two states are identified: a relaxed state at pH 4-8 (with the typical alignment of the crystallographic structure) and a compact state at pH 3-4 (with a tighter association and rotated alignment). This work shows that an approach based on constant-pH MD simulations can produce rich detailed pictures of pH-dependent protein associations, as illustrated for BLG dimerization.
Collapse
|
8
|
Ramamirtham S, Whitby CP, Zare D, Weeks M, Williams MA. The rheological properties of bovine β-Lactoglobulin stabilized oil/water interfaces depend on the protein's quaternary structure. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2021.106834] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
9
|
Leischner C, Egert S, Burkard M, Venturelli S. Potential Protective Protein Components of Cow's Milk against Certain Tumor Entities. Nutrients 2021; 13:1974. [PMID: 34201342 PMCID: PMC8228601 DOI: 10.3390/nu13061974] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/28/2021] [Accepted: 06/03/2021] [Indexed: 12/16/2022] Open
Abstract
Milk and dairy products, especially from cow's milk, play a major role in the daily human diet. It is therefore hardly surprising that the subject of milk is being extensively researched and that many effects of individual milk components have been characterized as a result. With the wealth of results available today, the influence of milk on the development of various types of cancer and, in particular, its often protective effects have been shown both in vitro and in vivo and in the evaluation of large-scale cohort and case-control studies. Various caseins, diverse whey proteins such as α-lactalbumin (α-LA), bovine α-lactalbumin made lethal to tumor cells (BAMLET), β-lactoglobulin (β-LG), or bovine serum albumin (BSA), and numerous milk fat components, such as conjugated linoleic acid (CLA), milk fat globule membrane (MFGM), or butyrate, as well as calcium and other protein components such as lactoferrin (Lf), lactoferricin (Lfcin), and casomorphines, show antitumor or cytotoxic effects on cells from different tumor entities. With regard to a balanced and health-promoting diet, milk consumption plays a major role in a global context. This work provides an overview of what is known about the antitumoral properties of proteins derived from cow's milk and their modes of action.
Collapse
Affiliation(s)
- Christian Leischner
- Institute of Nutritional Sciences 140, Nutritional Biochemistry 140c, University of Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany;
| | - Sarah Egert
- Institute of Nutritional Medicine, Nutritional Science/Dietetics 180c, University of Hohenheim, Fruwirthstr. 12, 70599 Stuttgart, Germany;
| | - Markus Burkard
- Institute of Nutritional Sciences 140, Nutritional Biochemistry 140c, University of Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany;
| | - Sascha Venturelli
- Institute of Nutritional Sciences 140, Nutritional Biochemistry 140c, University of Hohenheim, Garbenstr. 30, 70599 Stuttgart, Germany;
- Department of Vegetative and Clinical Physiology, Institute of Physiology, University Hospital Tuebingen, Wilhelmstr. 56, 72074 Tuebingen, Germany
| |
Collapse
|
10
|
Kaplan AR, Olson R, Alexandrescu AT. Protein yoga: Conformational versatility of the Hemolysin II C-terminal domain detailed by NMR structures for multiple states. Protein Sci 2021; 30:990-1005. [PMID: 33733504 DOI: 10.1002/pro.4066] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/10/2021] [Accepted: 03/13/2021] [Indexed: 11/05/2022]
Abstract
The C-terminal domain of Bacillus cereus hemolysin II (HlyIIC), stabilizes the trans-membrane-pore formed by the HlyII toxin and may aid in target cell recognition. Initial efforts to determine the NMR structure of HlyIIC were hampered by cis/trans isomerization about the single proline at position 405 that leads to doubling of NMR resonances. We used the mutant P405M-HlyIIC that eliminates the cis proline to determine the NMR structure of the domain, which revealed a novel fold. Here, we extend earlier studies to the NMR structure determination of the cis and trans states of WT-HlyIIC that exist simultaneously in solution. The primary structural differences between the cis and trans states are in the loop that contains P405, and structurally adjacent loops. Thermodynamic linkage analysis shows that at 25 C the cis proline, which already has a large fraction of 20% in the unfolded protein, increases to 50% in the folded state due to coupling with the global stability of the domain. The P405M or P405A substitutions eliminate heterogeneity due to proline isomerization but lead to the formation of a new dimeric species. The NMR structure of the dimer shows that it is formed through domain-swapping of strand β5, the last segment of secondary structure following P405. The presence of P405 in WT-HlyIIC strongly disfavors the dimer compared to the P405M-HlyIIC or P405A-HlyIIC mutants. The WT proline may thus act as a "gatekeeper," warding off aggregative misfolding.
Collapse
Affiliation(s)
- Anne R Kaplan
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| | - Rich Olson
- Department of Molecular Biology and Biochemistry, Molecular Biophysics Program, Wesleyan University, Middletown, Connecticut, USA
| | - Andrei T Alexandrescu
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut, USA
| |
Collapse
|
11
|
Madsen M, Westh P, Khan S, Ipsen R, Almdal K, Aachmann FL, Svensson B. Impact of Alginate Mannuronic-Guluronic Acid Contents and pH on Protein Binding Capacity and Complex Size. Biomacromolecules 2021; 22:649-660. [PMID: 33417429 DOI: 10.1021/acs.biomac.0c01485] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alginates, serving as hydrocolloids in the food and pharma industries, form particles at pH < 4.5 with positively charged proteins, such as β-lactoglobulin (β-Lg). Alginates are linear anionic polysaccharides composed of 1,4-linked β-d-mannuronate (M) and α-l-guluronate (G) residues. The impact of M and G contents and pH is investigated to correlate with the formation and size of β-Lg alginate complexes under relevant ionic strength. It is concluded, using three alginates of M/G ratios 0.6, 1.1, and 1.8 and similar molecular mass, that β-Lg binding capacity is higher at pH 4.0 than at pH 2.65 and for high M content. By contrast, the largest particles are obtained at pH 2.65 and with high G content. At pH 4.0 and 2.65, the stoichiometry was 28-48 and 3-10 β-Lg molecules bound per alginate, respectively, increasing with higher M content. The findings will contribute to the design of formation of the desired alginate-protein particles in the acidic pH range.
Collapse
Affiliation(s)
- Mikkel Madsen
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby Denmark
| | - Peter Westh
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby Denmark
| | - Sanaullah Khan
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby Denmark
| | - Richard Ipsen
- Department of Food Science, University of Copenhagen, DK-1958 Frederiksberg, Denmark
| | - Kristoffer Almdal
- Department of Chemistry, Technical University of Denmark, DK-2800 Kongens, Lyngby, Denmark
| | - Finn L Aachmann
- Norwegian Biopolymer Laboratory (NOBIPOL), Department of Biotechnology and Food Science, NTNU Norwegian University of Science and Technology, N-7491, Trondheim, Norway
| | - Birte Svensson
- Department of Biotechnology and Biomedicine, Technical University of Denmark, DK-2800 Kongens Lyngby Denmark
| |
Collapse
|
12
|
Seychell BC, Beck T. Molecular basis for protein-protein interactions. Beilstein J Org Chem 2021; 17:1-10. [PMID: 33488826 PMCID: PMC7801801 DOI: 10.3762/bjoc.17.1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 12/07/2020] [Indexed: 01/11/2023] Open
Abstract
This minireview provides an overview on the current knowledge of protein-protein interactions, common characterisation methods to characterise them, and their role in protein complex formation with some examples. A deep understanding of protein-protein interactions and their molecular interactions is important for a number of applications, including drug design. Protein-protein interactions and their discovery are thus an interesting avenue for understanding how protein complexes, which make up the majority of proteins, work.
Collapse
Affiliation(s)
- Brandon Charles Seychell
- Universität Hamburg, Department of Chemistry, Institute of Physical Chemistry, Grindelallee 117, 20146 Hamburg, Germany
| | - Tobias Beck
- Universität Hamburg, Department of Chemistry, Institute of Physical Chemistry, Grindelallee 117, 20146 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Hamburg, Germany
| |
Collapse
|
13
|
Isolation and Self-Association Studies of Beta-Lactoglobulin. Int J Mol Sci 2020; 21:ijms21249711. [PMID: 33352705 PMCID: PMC7766286 DOI: 10.3390/ijms21249711] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 12/31/2022] Open
Abstract
The aim of this study was to investigate isolated β-lactoglobulin (β-LG) from the whey protein isolate (WPI) solution using the column chromatography with SP Sephadex. The physicochemical characterization (self-association, the pH stability in various salt solutions, the identification of oligomeric forms) of the protein obtained have been carried out. The electrophoretically pure β-LG fraction was obtained at pH 4.8. The fraction was characterized by the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF/TOF MS) technique. The use of the HCCA matrix indicated the presence of oligomeric β-LG forms, while the SA and DHB matrices enabled the differentiation of A and B isoforms in the sample. The impact of sodium chloride, potassium chloride, ammonium sulfate, and sodium citrate in dispersion medium on β-LG electrophoretic stability in solution was also studied. Type of the dispersion medium led to the changes in the isoelectric point of protein. Sodium citrate stabilizes protein in comparison to ammonium sulfate. Additionally, the potential of capillary electrophoresis (CE) with UV detection using bare fused capillary to monitor β-LG oligomerization was discussed. Obtained CE data were further compared by the asymmetric flow field flow fractionation coupled with the multi-angle light scattering detector (AF4-MALS). It was shown that the β-LG is a monomer at pH 3.0, dimer at pH 7.0. At pH 5.0 (near the isoelectric point), oligomers with structures from dimeric to octameric are formed. However, the appearance of the oligomers equilibrium is dependent on the concentration of protein. The higher quantity of protein leads to the formation of the octamer. The far UV circular dichroism (CD) spectra carried out at pH 3.0, 5.0, and 7.0 confirmed that β-sheet conformation is dominant at pH 3.0, 5.0, while at pH 7.0, this conformation is approximately in the same quantity as α-helix and random structures.
Collapse
|
14
|
Bonì F, Marino V, Bidoia C, Mastrangelo E, Barbiroli A, Dell’Orco D, Milani M. Modulation of Guanylate Cyclase Activating Protein 1 (GCAP1) Dimeric Assembly by Ca 2+ or Mg 2+: Hints to Understand Protein Activity. Biomolecules 2020; 10:biom10101408. [PMID: 33027977 PMCID: PMC7600425 DOI: 10.3390/biom10101408] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 09/30/2020] [Accepted: 10/01/2020] [Indexed: 11/16/2022] Open
Abstract
The guanylyl cyclase-activating protein 1, GCAP1, activates or inhibits retinal guanylyl cyclase (retGC) depending on cellular Ca2+ concentrations. Several point mutations of GCAP1 have been associated with impaired calcium sensitivity that eventually triggers progressive retinal degeneration. In this work, we demonstrate that the recombinant human protein presents a highly dynamic monomer-dimer equilibrium, whose dissociation constant is influenced by salt concentration and, more importantly, by protein binding to Ca2+ or Mg2+. Based on small-angle X-ray scattering data, protein-protein docking, and molecular dynamics simulations we propose two novel three-dimensional models of Ca2+-bound GCAP1 dimer. The different propensity of human GCAP1 to dimerize suggests structural differences induced by cation binding potentially involved in the regulation of retGC activity.
Collapse
Affiliation(s)
- Francesco Bonì
- CNR-IBF, Istituto di Biofisica, Via Celoria 26, I-20133 Milan, Italy; (F.B.); (C.B.); (E.M.)
- Dipartimento di Bioscienze, Università di Milano, Via Celoria 26, I-20133 Milan, Italy
| | - Valerio Marino
- Dipartimento di Neuroscienze, Biomedicina e Movimento, Sezione di Chimica Biologica, Università di Verona, I-37134 Verona, Italy;
| | - Carlo Bidoia
- CNR-IBF, Istituto di Biofisica, Via Celoria 26, I-20133 Milan, Italy; (F.B.); (C.B.); (E.M.)
- Dipartimento di Bioscienze, Università di Milano, Via Celoria 26, I-20133 Milan, Italy
| | - Eloise Mastrangelo
- CNR-IBF, Istituto di Biofisica, Via Celoria 26, I-20133 Milan, Italy; (F.B.); (C.B.); (E.M.)
- Dipartimento di Bioscienze, Università di Milano, Via Celoria 26, I-20133 Milan, Italy
| | - Alberto Barbiroli
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l’Ambiente, Università degli Studi di Milano, Via Celoria 2, I-20133 Milan, Italy;
| | - Daniele Dell’Orco
- Dipartimento di Neuroscienze, Biomedicina e Movimento, Sezione di Chimica Biologica, Università di Verona, I-37134 Verona, Italy;
- Correspondence: (D.D.); (M.M.); Tel.: +39-045-802-7637 (D.D.); +39-02-5031-4890 (M.M.)
| | - Mario Milani
- CNR-IBF, Istituto di Biofisica, Via Celoria 26, I-20133 Milan, Italy; (F.B.); (C.B.); (E.M.)
- Dipartimento di Bioscienze, Università di Milano, Via Celoria 26, I-20133 Milan, Italy
- Correspondence: (D.D.); (M.M.); Tel.: +39-045-802-7637 (D.D.); +39-02-5031-4890 (M.M.)
| |
Collapse
|
15
|
|
16
|
β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 4. Impact on the Stability of Foam Films and Foams. MINERALS 2020. [DOI: 10.3390/min10070636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The complexity and high sensitivity of proteins to environmental factors give rise to a multitude of variables, which affect the stabilization mechanisms in protein foams. Interfacial and foaming properties of proteins have been widely studied, but the reported unique effect of pH, which can be of great interest to applications, has been investigated to a lesser extent. In this paper, we focus on the impact of pH on the stability of black foam films and corresponding foams obtained from solutions of a model globular protein—the whey β-lactoglobulin (BLG). Foam stability was analyzed utilizing three characteristic parameters (deviation time, transition time and half-lifetime) for monitoring the foam decay, while foam film stability was measured in terms of the critical disjoining pressure of film rupture. We attempt to explain correlations between the macroscopic properties of a foam system and those of its major building blocks (foam films and interfaces), and thus, to identify structure-property relationships in foam. Good correlations were found between the stabilities of black foam films and foams, while relations to the properties of adsorption layers appeared to be intricate. That is because pH-dependent interfacial properties of proteins usually exhibit an extremum around the isoelectric point (pI), but the stability of BLG foam films increases with increasing pH (3–7), which is well reflected in the foam stability. We discuss the possible reasons behind these intriguingly different behaviors on the basis of pH-induced changes in the molecular properties of BLG, which seem to be determining the mechanism of film rupture at the critical disjoining pressure.
Collapse
|
17
|
Martínez-López AL, Pangua C, Reboredo C, Campión R, Morales-Gracia J, Irache JM. Protein-based nanoparticles for drug delivery purposes. Int J Pharm 2020; 581:119289. [DOI: 10.1016/j.ijpharm.2020.119289] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/27/2020] [Accepted: 03/28/2020] [Indexed: 02/07/2023]
|
18
|
Maknun L, Sumranjit J, Siripinyanond A. Use of flow field-flow fractionation and single particle inductively coupled plasma mass spectrometry for size determination of selenium nanoparticles in a mixture. RSC Adv 2020; 10:6423-6435. [PMID: 35495991 PMCID: PMC9049635 DOI: 10.1039/c9ra07120b] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 02/05/2020] [Indexed: 12/15/2022] Open
Abstract
Various analytical techniques have been used for size analysis of selenium nanoparticles (SeNPs). These include flow field-flow fractionation (FlFFF), single particle inductively coupled plasma mass spectrometry (SP-ICP-MS), dynamic light scattering (DLS) and transmission electron microscopy (TEM). For hydrodynamic diameter estimation, the FlFFF technique was used and the results were compared with those analyzed by DLS. For core diameter estimation, the results obtained from SP-ICP-MS were compared with those from TEM. Two types of FlFFF channel were employed, i.e., symmetrical FlFFF (Sy-FlFFF) and asymmetrical FlFFF (Asy-FlFFF). Considering the use of FlFFF, optimization was performed on a Sy-FlFFF channel to select the most appropriate carrier liquid and membrane in order to minimize problems due to particle membrane interaction. The use of FL-70 and 10 kDa RC provided an acceptable compromise peak quality and size accuracy for all samples of SeNPs which were coated by proteins (positively charged SeNPs) and sodium dodecyl sulfate (negatively charged SeNPs). FlFFF always yielded the lower estimate of the hydrodynamic size than DLS as a reference method. The results obtained by SP-ICP-MS were consistent with the TEM method for the core diameter estimation. The results from FlFFF and the DLS reference method were significantly different as confirmed by paired t-test analysis, while the results provided by SP-ICP-MS and the TEM reference method were not significantly different. Furthermore, consecutive size analysis by SP-ICP-MS for the fractions collected from FlFFF was proposed for sizing of SeNP mixtures. The combined technique helps to improve the size analysis in the complex samples and shows more advantages than using only SP-ICP-MS.
Collapse
Affiliation(s)
- Luluil Maknun
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University Rama VI Road Bangkok 10400 Thailand +66-2-354-7151 +66-2-201-5195
| | - Jitapa Sumranjit
- National Nanotechnology Center, National Science and Technology Development Agency 111 Phahonyothin Rd., Klongluang Pathumthani 12120 Thailand
| | - Atitaya Siripinyanond
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Mahidol University Rama VI Road Bangkok 10400 Thailand +66-2-354-7151 +66-2-201-5195
| |
Collapse
|
19
|
Srivastava R, Chattopadhyaya M, Bandyopadhyay P. Calculation of salt-dependent free energy of binding of β-lactoglobulin homodimer formation and mechanism of dimer formation using molecular dynamics simulation and three-dimensional reference interaction site model (3D-RISM): diffuse salt ions and non-polar interactions between the monomers favor the dimer formation. Phys Chem Chem Phys 2020; 22:2142-2156. [PMID: 31912070 DOI: 10.1039/c9cp05578a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
There are several important phenomena in chemistry, biology, and physics where molecules (or parts of a molecule) having charges of the same sign come closer together and become stable. DNA condensation, RNA folding, colloid-colloid interactions are some of the examples of this kind. In the current work, we have investigated how β-lactoglobulin, a protein found in milk, in spite of carrying +13 charge, favors the homodimer formation in the presence of salt. We have focussed on calculating the protein-protein binding free energy in the presence of salt and identifying the thermodynamic and microscopic mechanism of the process. Estimation of binding free energy of this salt-dependent process is done by combining molecular dynamics simulation with statistical mechanical theory of three-dimensional reference interaction site model (3D-RISM). Binding free energy is evaluated from the chemical potential of the solutes as opposed to potential of mean force calculation, which gives only a constrained free energy. Our calculated values semi-quantitatively match with the experimental results. By examining the different components of binding free energy, we have found that the role of salt ions (especially of Cl-) is to shift the equilibrium towards the dimer. Non-polar (Lennard-Jones) interactions between the monomers is also favorable to the binding free energy. However, water slightly disfavors the dimer formation. For the microscopic mechanism, heterogeneous of both Na+ and Cl- near the charged residues at the binding interface and change of this charge distribution on dimer formation contribute to the stability. A fine-tuning of enthalpic and entropic effects of salt ions is found to operate at different salt concentrations. Both thermodynamic and microscopic mechanism of dimer formation gives detailed insight into the complex electrostatics of charged protein-protein binding.
Collapse
Affiliation(s)
- Rakesh Srivastava
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India.
| | | | - Pradipta Bandyopadhyay
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi, India.
| |
Collapse
|
20
|
Gochev GG, Scoppola E, Campbell RA, Noskov BA, Miller R, Schneck E. β-Lactoglobulin Adsorption Layers at the Water/Air Surface: 3. Neutron Reflectometry Study on the Effect of pH. J Phys Chem B 2019; 123:10877-10889. [PMID: 31725291 DOI: 10.1021/acs.jpcb.9b07733] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Several characteristics of β-lactoglobulin (BLG) layers adsorbed at the air/water interface exhibit a strong pH dependence, but our knowledge on the underlying structure-property relations is still fragmental. Here, we therefore extend our recent studies by neutron reflectometry (NR) and provide a comprehensive overview through direct measurements of the surface excess Γ and the layers' molecular structure. This enables comparison with available literature data to draw general conclusions. The NR experiments were performed at various pH values and within a wide range of protein concentrations, CBLG. Adsorption kinetics measurements in air-contrast-matched-water and over a narrow Qz range enabled direct quantification of the dynamic surface excess Γ(t) and are found to be consistent with ellipsometry data. Near the isoelectric point, pI, the rates of adsorption and Γ are maximal but only at sufficiently high CBLG. NR data collected over a wider Qz range and in two aqueous isotopic contrasts revealed the structure of adsorbed BLG layers at a steady state close to equilibrium. Independent of the pH, BLG was found to form dense monolayers with average thicknesses of 1.1 nm, suggesting flattening of the BLG globules upon adsorption as compared with their bulk dimensions (≈3.5 nm). Near pI and at sufficiently high CBLG, a thick (≈5.5 nm) but looser secondary sublayer is additionally formed adjacent to the dense primary monolayer. The thickness of this sublayer can be interpreted in terms of disordered BLG dimers. The results obtained and notably the specific interfacial structuring of BLG near pI complement previous observations relating the impact of solution pH and CBLG on other interfacial characteristics such as surface pressure and surface dilational viscoelasticity modulus.
Collapse
Affiliation(s)
- Georgi G Gochev
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany.,Institute of Physical Chemistry , Bulgarian Academy of Sciences , 1113 Sofia , Bulgaria
| | - Ernesto Scoppola
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| | - Richard A Campbell
- Institut Laue-Langevin , 71 Avenue des Martyrs, CS20156 , 38042 Grenoble , France.,Division of Pharmacy and Optometry , University of Manchester , M13 9PT Manchester , U.K
| | - Boris A Noskov
- Institute of Chemistry , St. Petersburg State University , 198504 Saint-Petersburg , Russia
| | - Reinhard Miller
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| | - Emanuel Schneck
- Max Planck Institute of Colloids and Interfaces , 14476 Potsdam , Germany
| |
Collapse
|
21
|
Orcajo J, Lavilla M, Martínez-de-Marañón I. Effect of Pulsed Light treatment on β-lactoglobulin immunoreactivity. Lebensm Wiss Technol 2019. [DOI: 10.1016/j.lwt.2019.05.129] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
|
22
|
Eldrid C, Ujma J, Kalfas S, Tomczyk N, Giles K, Morris M, Thalassinos K. Gas Phase Stability of Protein Ions in a Cyclic Ion Mobility Spectrometry Traveling Wave Device. Anal Chem 2019; 91:7554-7561. [PMID: 31117399 PMCID: PMC7006968 DOI: 10.1021/acs.analchem.8b05641] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
Ion
mobility mass spectrometry (IM-MS) allows separation of native
protein ions into “conformational families”. Increasing
the IM resolving power should allow finer structural information to
be obtained and can be achieved by increasing the length of the IM
separator. This, however, increases the time that protein ions spend
in the gas phase and previous experiments have shown that the initial
conformations of small proteins can be lost within tens of milliseconds.
Here, we report on investigations of protein ion stability using a
multipass traveling wave (TW) cyclic IM (cIM) device. Using this device,
minimal structural changes were observed for Cytochrome C after hundreds
of milliseconds, while no changes were observed for a larger multimeric
complex (Concanavalin A). The geometry of the instrument (Q-cIM-ToF)
also enables complex tandem IM experiments to be performed, which
were used to obtain more detailed collision-induced unfolding pathways
for Cytochrome C. The instrument geometry provides unique capabilities
with the potential to expand the field of protein analysis via IM-MS.
Collapse
Affiliation(s)
- Charles Eldrid
- Institute of Structural and Molecular Biology, Division of Biosciences , University College London , London , WC1E 6BT , United Kingdom
| | - Jakub Ujma
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Symeon Kalfas
- Institute of Structural and Molecular Biology, Division of Biosciences , University College London , London , WC1E 6BT , United Kingdom
| | - Nick Tomczyk
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Kevin Giles
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Mike Morris
- Waters Corporation , Wilmslow , SK9 4AX , United Kingdom
| | - Konstantinos Thalassinos
- Institute of Structural and Molecular Biology, Division of Biosciences , University College London , London , WC1E 6BT , United Kingdom.,Institute of Structural and Molecular Biology, Birkbeck College , University of London , London , WC1E 7HX , United Kingdom
| |
Collapse
|
23
|
Pandey P, Meena NK, Prakash A, Kumar V, Lynn AM, Ahmad F. Characterization of heterogeneous intermediate ensembles on the guanidinium chloride-induced unfolding pathway of β-lactoglobulin. J Biomol Struct Dyn 2019; 38:1042-1053. [PMID: 30880641 DOI: 10.1080/07391102.2019.1593245] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Folding pathway of β-LgA (β-lactoglobulin) evolves through the conformational α→β transition. The α→β transition is a molecular hallmark of various neurodegenerative diseases. Thus, β-LgA may serve as a good model for understanding molecular mechanism of protein aggregation involved in neurodegenerative diseases. Here, we studied the conformational dynamics of β-LgA in 6 M GdmCl at different temperatures using MD simulations. Structural order parameters such as RMSD, Rg, SASA, native contacts (Q), hydrophobic distal-matrix and free-energy landscape (FEL) were used to investigate the conformational transitions. Our results show that GdmCl destabilizes secondary and tertiary structure of β-LgA by weakening the hydrophobic interactions and hydrogen bond network. Multidimensional FEL shows the presence of different unfolding intermediates at 400 K. I1 is long-lived intermediate which has mostly intact native secondary structure, but loose tertiary structure. I2 is structurally compact intermediate formed after the partial loss of secondary structure. The transiently and infrequently buried evolution of W19 shows that intermediate conformational ensembles are structurally heterogeneous. We observed that the intermediate conformations are largely stabilized by non-native H-bonds. The outcome of this work provides the molecular details of intermediates trapped due to non-native interactions that may be regarded as pathogenic conformations involved in neurodegenerative diseases.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Preeti Pandey
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Naveen Kumar Meena
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Amresh Prakash
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Vijay Kumar
- Amity Institute of Neuropsychology & Neurosciences, Amity University, Noida, India
| | - Andrew M Lynn
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Faizan Ahmad
- Jamia Millia Islamia, Centre for Interdisciplinary Research in Basic Sciences, New Delhi, India
| |
Collapse
|
24
|
|
25
|
β-Lactoglobulin associative interactions: a small-angle scattering study. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2019; 48:285-295. [DOI: 10.1007/s00249-019-01360-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/27/2019] [Accepted: 03/14/2019] [Indexed: 02/02/2023]
|
26
|
Allahdad Z, Varidi M, Zadmard R, Saboury AA, Haertlé T. Binding of β-carotene to whey proteins: Multi-spectroscopic techniques and docking studies. Food Chem 2019; 277:96-106. [DOI: 10.1016/j.foodchem.2018.10.057] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 10/10/2018] [Accepted: 10/10/2018] [Indexed: 01/22/2023]
|
27
|
Conformational state and charge determine the interfacial stabilization process of beta-lactoglobulin at preoccupied interfaces. J Colloid Interface Sci 2019; 536:300-309. [DOI: 10.1016/j.jcis.2018.10.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 10/16/2018] [Accepted: 10/17/2018] [Indexed: 01/19/2023]
|
28
|
Khan S, Ipsen R, Almdal K, Svensson B, Harris P. Revealing the Dimeric Crystal and Solution Structure of β-Lactoglobulin at pH 4 and Its pH and Salt Dependent Monomer–Dimer Equilibrium. Biomacromolecules 2018; 19:2905-2912. [DOI: 10.1021/acs.biomac.8b00471] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sanaullah Khan
- Enzyme and Protein Chemistry, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 224, DK-2800 Kgs. Lyngby, Denmark
- Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, Building 423, DK-2800 Kgs. Lyngby, Denmark
| | - Richard Ipsen
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, DK-1958 Frederiksberg, Denmark
| | - Kristoffer Almdal
- Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, Building 423, DK-2800 Kgs. Lyngby, Denmark
| | - Birte Svensson
- Enzyme and Protein Chemistry, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 224, DK-2800 Kgs. Lyngby, Denmark
| | - Pernille Harris
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, DK-2800 Kgs. Lyngby, Denmark
| |
Collapse
|
29
|
Crowther JM, Allison JR, Smolenski GA, Hodgkinson AJ, Jameson GB, Dobson RCJ. The self-association and thermal denaturation of caprine and bovine β-lactoglobulin. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2018; 47:739-750. [PMID: 29663020 DOI: 10.1007/s00249-018-1300-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 02/27/2018] [Accepted: 04/10/2018] [Indexed: 11/29/2022]
Abstract
Milk components, such as proteins and lipids, have different physicochemical properties depending upon the mammalian species from which they come. Understanding the different responses of these milks to digestion, processing, and differences in their immunogenicity requires detailed knowledge of these physicochemical properties. Here we report on the oligomeric state of β-lactoglobulin from caprine milk, the most abundant protein present in the whey fraction. At pH 2.5 caprine β-lactoglobulin is predominantly monomeric, whereas bovine β-lactoglobulin exists in a monomer-dimer equilibrium at the same protein concentrations. This behaviour was also observed in molecular dynamics simulations and can be rationalised in terms of the amino acid substitutions present between caprine and bovine β-lactoglobulin that result in a greater positive charge on each subunit of caprine β-lactoglobulin at low pH. The denaturation of β-lactoglobulin when milk is heat-treated contributes to the fouling of heat-exchange surfaces, reducing yields and increasing cleaning costs. The bovine and caprine orthologues of β-lactoglobulin display different responses to thermal treatment, with caprine β-lactoglobulin precipitating at higher pH values than bovine β-lactoglobulin (pH 7.1 compared to pH 5.6) that are closer to the natural pH of these milks (pH 6.7). This property of caprine β-lactoglobulin likely contributes to the reduced heat stability of caprine milk compared to bovine milk at its natural pH.
Collapse
Affiliation(s)
- Jennifer M Crowther
- School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand
- Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
| | - Jane R Allison
- Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
- Centre for Theoretical Chemistry and Physics, Institute of Natural and Mathematical Sciences, Massey University, Auckland, New Zealand
| | - Grant A Smolenski
- Food and Bio-Based Products, AgResearch Limited, Ruakura Research Centre, Hamilton, New Zealand
- MS3 Solutions Ltd, Ruakura Research Centre, Hamilton, 3240, New Zealand
| | - Alison J Hodgkinson
- Food and Bio-Based Products, AgResearch Limited, Ruakura Research Centre, Hamilton, New Zealand
| | - Geoffrey B Jameson
- Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand
- Institute of Fundamental Sciences, Massey University, Palmerston North, New Zealand
- The Riddet Institute, Massey University, Palmerston North, New Zealand
| | - Renwick C J Dobson
- School of Biological Sciences, University of Canterbury, PO Box 4800, Christchurch, 8140, New Zealand.
- Biomolecular Interaction Centre, University of Canterbury, Christchurch, New Zealand.
- The Riddet Institute, Massey University, Palmerston North, New Zealand.
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Parkville, VIC, Australia.
| |
Collapse
|
30
|
Sengupta B, Das N, Sen P. Monomerization and aggregation of β-lactoglobulin under adverse condition: A fluorescence correlation spectroscopic investigation. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2018; 1866:316-326. [DOI: 10.1016/j.bbapap.2017.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Revised: 11/01/2017] [Accepted: 11/12/2017] [Indexed: 12/26/2022]
|
31
|
Stender EG, Khan S, Ipsen R, Madsen F, Hägglund P, Hachem MA, Almdal K, Westh P, Svensson B. Effect of alginate size, mannuronic/guluronic acid content and pH on particle size, thermodynamics and composition of complexes with β-lactoglobulin. Food Hydrocoll 2018. [DOI: 10.1016/j.foodhyd.2017.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
32
|
Khan S, Birch J, Van Calsteren MR, Ipsen R, Peters GHJ, Svensson B, Harris P, Almdal K. Interaction between structurally different heteroexopolysaccharides and β-lactoglobulin studied by solution scattering and analytical ultracentrifugation. Int J Biol Macromol 2018; 111:746-754. [PMID: 29329814 DOI: 10.1016/j.ijbiomac.2018.01.050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 12/24/2017] [Accepted: 01/08/2018] [Indexed: 12/28/2022]
Abstract
Despite a very large number of bacterial exopolysaccharides have been reported, detailed knowledge on their molecular structures and associative interactions with proteins is lacking. Small-angle X-ray scattering, dynamic light scattering and analytical ultracentrifugation (AUC) were used to characterize the interactions of six lactic acid bacterial heteroexopolysaccharides (HePS-1-HePS-6) with β-lactoglobulin (BLG). Compared to free HePSs, a large increase in the X-ray radius of gyration RG, maximum length L and hydrodynamic diameter dH of HePS-1-HePS-4 mixed with BLG revealed strong aggregation, the extent of which depended on the compact conformation and degree of branching of these HePSs. No significant effects were observed with HePS-5 and HePS-6. Turbidity and AUC analyses showed that both soluble and insoluble BLG-HePS complexes were formed. The findings provide new insights into the role of molecular structures in associative interactions between HePSs and BLG which has relevance for various industrial applications.
Collapse
Affiliation(s)
- Sanaullah Khan
- Enzyme and Protein Chemistry, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 224, DK-2800 Kgs. Lyngby, Denmark; Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, Building 423, DK-2800 Kgs. Lyngby, Denmark.
| | - Johnny Birch
- Enzyme and Protein Chemistry, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 224, DK-2800 Kgs. Lyngby, Denmark
| | - Marie-Rose Van Calsteren
- Saint-Hyacinthe Research and Development Centre, Agriculture and Agri-Food Canada, 3600 Casavant Boulevard West, Saint-Hyacinthe, Quebec J2S 8E3, Canada
| | - Richard Ipsen
- Department of Food Science, University of Copenhagen, Rolighedsvej 26, DK-1958 Frederiksberg, Denmark
| | - Günther H J Peters
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, DK-2800 Kgs. Lyngby, Denmark
| | - Birte Svensson
- Enzyme and Protein Chemistry, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, Building 224, DK-2800 Kgs. Lyngby, Denmark
| | - Pernille Harris
- Department of Chemistry, Technical University of Denmark, Kemitorvet, Building 207, DK-2800 Kgs. Lyngby, Denmark
| | - Kristoffer Almdal
- Department of Micro- and Nanotechnology, Technical University of Denmark, Ørsteds Plads, Building 423, DK-2800 Kgs. Lyngby, Denmark
| |
Collapse
|
33
|
Guo Y, Harris P, Kaur A, Pastrana L, Jauregi P. Characterisation of β-lactoglobulin nanoparticles and their binding to caffeine. Food Hydrocoll 2017. [DOI: 10.1016/j.foodhyd.2017.04.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
34
|
Sakurai K, Yagi M, Konuma T, Takahashi S, Nishimura C, Goto Y. Non-Native α-Helices in the Initial Folding Intermediate Facilitate the Ordered Assembly of the β-Barrel in β-Lactoglobulin. Biochemistry 2017; 56:4799-4807. [PMID: 28795569 DOI: 10.1021/acs.biochem.7b00458] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The roles of non-native α-helices frequently observed in the initial folding stage of β-sheet proteins have been examined for many years. We herein investigated the residue-level structures of several mutants of bovine β-lactoglobulin (βLG) in quenched-flow pH-pulse labeling experiments. βLG assumes a collapsed intermediate with a non-native α-helical structure (I0) in the early stage of folding, although its native form is predominantly composed of β-structures. The protection profile in I0 of pseudo-wild type (WT*) βLG was found to deviate from the pattern of the "average area buried upon folding" (AABUF). In particular, the level of protection at the region of strand A, at which non-native α-helices form in the I0 state, was significantly low compared to AABUF. G17E, the mutant with an increased helical propensity, showed a similar protection pattern. In contrast, the protection pattern for I0 of E44L, the mutant with an increased β-sheet propensity, was distinct from that of WT* and resembled the AABUF pattern. Transverse relaxation measurements demonstrated that the positions of the residual structures in the unfolded states of these mutants were consistent with those of the protected residues in the respective I0 states. On the basis of the slower conversion of I0 to the native state for E44L to that for WT*, non-native α-helices facilitate the ordered assembly of the β-barrel by preventing interactions that trap folding.
Collapse
Affiliation(s)
- Kazumasa Sakurai
- High Pressure Protein Research Center, Institute of Advanced Technology, Kindai University , 930 Nishimitani, Kinokawa, Wakayama 649-6493, Japan.,Institute for Protein Research, Osaka University , 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Masanori Yagi
- Research Institute for Microbial Diseases, Osaka University , 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Tsuyoshi Konuma
- Institute for Protein Research, Osaka University , 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Satoshi Takahashi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
| | - Chiaki Nishimura
- Faculty of Pharmaceutical Sciences, Teikyo Heisei University , 4-21-2 Nakano, Nakano-ku, Tokyo 164-8530, Japan
| | - Yuji Goto
- Institute for Protein Research, Osaka University , 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| |
Collapse
|
35
|
Jia Z, Li L, Chakravorty A, Alexov E. Treating ion distribution with Gaussian-based smooth dielectric function in DelPhi. J Comput Chem 2017; 38:1974-1979. [PMID: 28602026 PMCID: PMC5495612 DOI: 10.1002/jcc.24831] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2017] [Revised: 03/21/2017] [Accepted: 04/22/2017] [Indexed: 11/06/2022]
Abstract
The standard treatment of ions in the framework of the Poisson-Boltzmann equation relies on molecular surfaces, which are commonly constructed along with the Stern layer. The molecular surface determines where ions can be present. In the Gaussian-based smooth dielectric function in DelPhi, smooth boundaries between the solute and solvent take the place of molecular surface. Therefore, this invokes the question of how to model mobile ions in the water phase without a definite solute-solvent boundary. This article reports a natural extension of the Gaussian-based smooth dielectric function approach that treats mobile ions via Boltzmann distribution with an added desolvation penalty. Thus, ion concentration near macromolecules is governed by the local electrostatic potential and the desolvation penalty (from being partially desolvated). The approach is tested against the experimental salt dependence of binding free energy on 7 protein-protein complexes and 12 DNA-protein complexes, resulting in Pearson correlations of 0.95 and 0.88, respectively. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Zhe Jia
- Computational Biophysics and Bioinformatics, Department of Physics and Astronomy, Clemson University, Clemson, South Carolina, United States, 29634
| | - Lin Li
- Computational Biophysics and Bioinformatics, Department of Physics and Astronomy, Clemson University, Clemson, South Carolina, United States, 29634
| | - Arghya Chakravorty
- Computational Biophysics and Bioinformatics, Department of Physics and Astronomy, Clemson University, Clemson, South Carolina, United States, 29634
| | - Emil Alexov
- Computational Biophysics and Bioinformatics, Department of Physics and Astronomy, Clemson University, Clemson, South Carolina, United States, 29634
| |
Collapse
|
36
|
Xu AY, Melton LD, Ryan TM, Mata JP, Jameson GB, Rekas A, Williams MAK, McGillivray DJ. Sugar-coated proteins: the importance of degree of polymerisation of oligo-galacturonic acid on protein binding and aggregation. SOFT MATTER 2017; 13:2698-2707. [PMID: 28337496 DOI: 10.1039/c6sm02660e] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We have simplified the structural heterogeneity of protein-polysaccharide binding by investigating protein binding to oligosaccharides. The interactions between bovine beta-lactoglobulin A (βLgA) and oligo-galacturonic acids (OGAs) with various numbers of sugar residues have been investigated with a range of biophysical techniques. We show that the βLgA-OGA interaction is critically dependent on the length of the oligosaccharide. Isothermal titration calorimetry results suggest that a minimum length of 7 or 8 sugar residues is required in order to exhibit appreciable exothermic interactions with βLgA - shorter oligosaccharides show no enthalpic interactions at any concentration ratio. When titrating βLgA into OGAs with more than 7-8 sugar residues the sample solution also became turbid with increasing amounts of βLgA, indicating the formation of macroscopic assemblies. Circular dichroism, thioflavin T fluorescence and small angle X-ray/neutron scattering experiments revealed two structural regimes during the titration. When OGAs were in excess, βLgA formed discrete assemblies upon OGA binding, and no subsequent aggregation was observed. However, when βLgA was present in excess, multi-scale structures were formed and this eventually led to the separation of the solution into two liquid-phases.
Collapse
Affiliation(s)
- Amy Y Xu
- Riddet Institute Centre of Research Excellence, Private Bag 11222, Palmerston North 4442, New Zealand and School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| | - Laurence D Melton
- Riddet Institute Centre of Research Excellence, Private Bag 11222, Palmerston North 4442, New Zealand and School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand.
| | - Timothy M Ryan
- Australian Synchrotron, Clayton 3168, Victoria, Australia and The MacDiarmid Institute, Private Bag 600, Wellington 6140, New Zealand
| | - Jitendra P Mata
- ACNS, Australian Nuclear Science and Technology Organisation (ANSTO), Private Bag 2001, NSW 2232, Australia
| | - Geoffrey B Jameson
- Riddet Institute Centre of Research Excellence, Private Bag 11222, Palmerston North 4442, New Zealand and Institute of Fundamental Sciences, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
| | - Agata Rekas
- National Deuteration Facility, Australian Nuclear Science and Technology Organisation (ANSTO), Private Bag 2001, NSW 2232, Australia
| | - Martin A K Williams
- Riddet Institute Centre of Research Excellence, Private Bag 11222, Palmerston North 4442, New Zealand and The MacDiarmid Institute, Private Bag 600, Wellington 6140, New Zealand and Institute of Fundamental Sciences, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand
| | - Duncan J McGillivray
- School of Chemical Sciences, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand. and The MacDiarmid Institute, Private Bag 600, Wellington 6140, New Zealand
| |
Collapse
|
37
|
Molodenskiy D, Shirshin E, Tikhonova T, Gruzinov A, Peters G, Spinozzi F. Thermally induced conformational changes and protein–protein interactions of bovine serum albumin in aqueous solution under different pH and ionic strengths as revealed by SAXS measurements. Phys Chem Chem Phys 2017. [DOI: 10.1039/c6cp08809k] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Temperature-induced oligomerization of albumin before and after protein melting was studied using SAXS and interpreted in terms of interaction potential.
Collapse
Affiliation(s)
| | - Evgeny Shirshin
- Department of Physics
- M.V. Lomonosov Moscow State University
- Moscow
- Russia
| | - Tatiana Tikhonova
- International Laser Center
- M.V. Lomonosov Moscow State University
- Moscow
- Russia
| | | | - Georgy Peters
- National Research Centre “Kurchatov Institute”
- Moscow
- Russia
| | - Francesco Spinozzi
- Università Politecnica delle Marche
- Dipartimento di Scienze della Vita e dell'Ambiente
- Ancona
- Italy
| |
Collapse
|
38
|
Ulaganathan V, Gochev G, Gehin-Delval C, Leser M, Gunes D, Miller R. Effect of pH and electrolyte concentration on rising air bubbles in β-lactoglobulin solutions. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2016.03.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
39
|
Gomaa AI, Nsonzi F, Sedman J, Ismail AA. Enhanced Unfolding of Bovine β-Lactoglobulin Structure Using Microwave Treatment: a Multi-Spectroscopic Study. FOOD BIOPHYS 2016. [DOI: 10.1007/s11483-016-9451-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
40
|
Morschheuser L, Wessels H, Pille C, Fischer J, Hünniger T, Fischer M, Paschke-Kratzin A, Rohn S. HPTLC-aptastaining - Innovative protein detection system for high-performance thin-layer chromatography. Sci Rep 2016; 6:26665. [PMID: 27220270 PMCID: PMC4879557 DOI: 10.1038/srep26665] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 05/03/2016] [Indexed: 02/07/2023] Open
Abstract
Protein analysis using high-performance thin-layer chromatography (HPTLC) is not commonly used but can complement traditional electrophoretic and mass spectrometric approaches in a unique way. Due to various detection protocols and possibilities for hyphenation, HPTLC protein analysis is a promising alternative for e.g., investigating posttranslational modifications. This study exemplarily focused on the investigation of lysozyme, an enzyme which is occurring in eggs and technologically added to foods and beverages such as wine. The detection of lysozyme is mandatory, as it might trigger allergenic reactions in sensitive individuals. To underline the advantages of HPTLC in protein analysis, the development of innovative, highly specific staining protocols leads to improved sensitivity for protein detection on HPTLC plates in comparison to universal protein derivatization reagents. This study aimed at developing a detection methodology for HPTLC separated proteins using aptamers. Due to their affinity and specificity towards a wide range of targets, an aptamer based staining procedure on HPTLC (HPTLC-aptastaining) will enable manifold analytical possibilities. Besides the proof of its applicability for the very first time, (i) aptamer-based staining of proteins is applicable on different stationary phase materials and (ii) furthermore, it can be used as an approach for a semi-quantitative estimation of protein concentrations.
Collapse
Affiliation(s)
- Lena Morschheuser
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Hauke Wessels
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Christina Pille
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Judith Fischer
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Tim Hünniger
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Markus Fischer
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Angelika Paschke-Kratzin
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| | - Sascha Rohn
- University of Hamburg, Hamburg School of Food Science, Institute of Food Chemistry, Grindelallee 117, D-20146 Hamburg
| |
Collapse
|
41
|
Structural and thermo-rheological analysis of solutions and gels of a β-lactoglobulin fraction isolated from bovine whey. Food Chem 2016; 198:45-53. [DOI: 10.1016/j.foodchem.2015.11.090] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 10/01/2015] [Accepted: 11/16/2015] [Indexed: 11/20/2022]
|
42
|
Thawari AG, Rao CP. Peroxidase-like Catalytic Activity of Copper-Mediated Protein-Inorganic Hybrid Nanoflowers and Nanofibers of β-Lactoglobulin and α-Lactalbumin: Synthesis, Spectral Characterization, Microscopic Features, and Catalytic Activity. ACS APPLIED MATERIALS & INTERFACES 2016; 8:10392-10402. [PMID: 27049752 DOI: 10.1021/acsami.5b12591] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A free Cys-SH-containing protein, β-lactoglobulin (β-LG), and another protein not possessing the same, viz., apo-α-lactoglobulin (apo-α-LA), were used in studies to demonstrate the role of this amino acid, along with its secondary structure, in the formation of a protein dimer and a protein-inorganic hybrid nanoflower and in the creation of the peroxidase-like activity of the nanomaterials produced when the proteins were treated with varying Cu(2+) concentration under different pH conditions. An increase in the pH as well as the Cu(2+) mole ratio results in increasing dimer formation in case of β-LG due to the presence of free Cys121-SH, while the dimer is not formed in case of apo-α-LA under the same conditions. The role of Cys in the dimer formation has been demonstrated both by MALDI and sodium dodecyl sulfate-polyacrylamide gel electrophoresis studies. Both of the proteins exhibited changes in their secondary structures to different extents as a function of pH, and the structures were stabilized by Cu(2+) interactions, as studied by CD and fluorescence spectroscopy. The small and spherical nanoparticles formed at pH 7 with lower equivalents of Cu(2+) join together to form larger aggregates at higher equivalents of Cu(2+). For the same concentration at pH 9, both the aggregates and the nanoflowers were noticed. However, at pH 12, the Cu(2+) binding induces the formation of fibers along with the flowers. Both the nanoflowers and nanofibers exhibited peroxidase-like activity in a catalytic manner. Nanoflowers were also shown to detect phenol in the concentration range from 10 to 200 μM. The copper-induced nanobiomaterial obtained in the case of apo-α-LA also exhibited peroxidase-like activity. Thus, this paper deals with the green synthesis of copper-induced protein (β-LG/apo-α-LA)-inorganic hybrid nanomaterials that are important due to their applications as nanobiomaterials.
Collapse
Affiliation(s)
- Atul Gajanan Thawari
- Bioinorganic Laboratory, Department of Chemistry, Indian Institute of Technology Bombay , Powai, Mumbai 400 076, India
| | - Chebrolu Pulla Rao
- Bioinorganic Laboratory, Department of Chemistry, Indian Institute of Technology Bombay , Powai, Mumbai 400 076, India
| |
Collapse
|
43
|
Zare D, Allison JR, McGrath KM. Molecular Dynamics Simulation of β-Lactoglobulin at Different Oil/Water Interfaces. Biomacromolecules 2016; 17:1572-81. [DOI: 10.1021/acs.biomac.5b01709] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Davoud Zare
- MacDiarmid
Institute for Advanced Materials and Nanotechnology, School of Chemical
and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand
- Riddet
Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
| | - Jane R. Allison
- Centre
for Theoretical Chemistry and Physics, Institute of Natural and Mathematical
Sciences, Massey University Auckland (Oteha Rohe), Albany Highway, Albany 0632, New Zealand
- Biomolecular
Interaction Centre, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand
- Maurice
Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland 1023, New Zealand
| | - Kathryn M. McGrath
- MacDiarmid
Institute for Advanced Materials and Nanotechnology, School of Chemical
and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand
- Riddet
Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
| |
Collapse
|
44
|
Stegen J, van der Schoot P. Self-crowding induced phase separation in protein dispersions. J Chem Phys 2016; 142:244901. [PMID: 26133451 DOI: 10.1063/1.4922927] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The coupling between protein conformation, molecular volume, and solution phase behaviour is studied theoretically for a two-state, coarse-grained protein model in which protein molecules can reversibly switch between a native and a non-native excited state. In the model, native and non-native conformers are represented by perfect spheres with different hard-core diameters. We presume the larger, non-native species to attract each other through some unspecified potential. We find that at low concentrations the native state is stabilised energetically and that at high concentrations the native state is again stabilised but this time by self-crowding, i.e., a lack of free volume. These two regimes are separated by two first-order transitions from a region where the non-native conformational state is prevalent, stabilised by attractive interactions between the proteins. The calculated phase diagram is very sensitive to even quite small differences in particle volumes and has unusual features, including the loss of a critical point if the size difference is sufficiently large.
Collapse
Affiliation(s)
- J Stegen
- Applied Physics, Eindhoven University of Technology, Eindhoven 5600 MB, The Netherlands
| | - P van der Schoot
- Applied Physics, Eindhoven University of Technology, Eindhoven 5600 MB, The Netherlands
| |
Collapse
|
45
|
Chen S, Land H, Berglund P, Humble MS. Stabilization of an amine transaminase for biocatalysis. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.molcatb.2015.11.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
46
|
Chen J, Kong Y, Wo Y, Fang H, Li Y, Zhang T, Dong Y, Ge Y, Wu Z, Zhou D, Chen S. Facile synthesis of β-lactoglobulin capped Ag2S quantum dots for in vivo imaging in the second near-infrared biological window. J Mater Chem B 2016; 4:6271-6278. [PMID: 32263639 DOI: 10.1039/c6tb01186a] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Effectivein vivofluorescence imaging based on β-LG-Ag2S quantum dots at the second near-infrared region.
Collapse
|
47
|
sardar S, Maity S, Pal S, Parvej H, Das N, Sepay N, Sarkar M, Halder UC. Facile synthesis and characterization of beta lactoglobulin–copper nanocomposites having antibacterial applications. RSC Adv 2016. [DOI: 10.1039/c6ra14162e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The synthesis of Cu0 nanoparticles and Cu–protein nanocomposites is a great challenge.
Collapse
Affiliation(s)
- Subrata sardar
- Department of Chemistry
- Jadavpur University
- Kolkata – 700032
- India
| | - Sanhita Maity
- Department of Chemistry
- Jadavpur University
- Kolkata – 700032
- India
| | - Sampa Pal
- Department of Chemistry
- Jadavpur University
- Kolkata – 700032
- India
| | - Hasan Parvej
- Department of Chemistry
- Jadavpur University
- Kolkata – 700032
- India
| | - Niloy Das
- Department of Chemistry
- Durgapur Govt. College
- Durgapur
- India
| | - Nayim Sepay
- Department of Chemistry
- Jadavpur University
- Kolkata – 700032
- India
| | - Manas Sarkar
- Department of Physics
- Jadavpur University
- Kolkata – 700032
- India
| | | |
Collapse
|
48
|
Zhang Z, Vachet RW. Kinetics of Protein Complex Dissociation Studied by Hydrogen/Deuterium Exchange and Mass Spectrometry. Anal Chem 2015; 87:11777-83. [PMID: 26531682 DOI: 10.1021/acs.analchem.5b03123] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The growing importance of protein aggregation diseases requires the development of new methods to elucidate the molecular features that are responsible for the incipient protein-protein interactions. Kinetic information from protein-protein association/dissociation reactions is particularly valuable for revealing mechanistic insight, but robust tools that can provide this information are somewhat lacking. In this work, we describe a hydrogen/deuterium exchange (HDX)-based method that provides rate constant information for protein oligomer dissociation, using the well-studied β-lactoglobulin (βLG) dimer as a model system to validate our approach. By measuring the rate of exchange at different regions of the protein using top-down tandem mass spectrometry and fitting the resulting data to an appropriate mathematical model, we are able to extract the dimer's dissociation rate constant. We exploit the fact that regions of the protein that are part of the protein-protein interface have exchange patterns that are distinct from noninterfacial regions. This observation indicates that the HDX/MS method not only provides kinetic information but also could provide structural insight about the interface at the same time, which would be very valuable for previously uncharacterized protein-protein complexes.
Collapse
Affiliation(s)
- Zhe Zhang
- Department of Chemistry, University of Massachusetts , LGRT 104, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | - Richard W Vachet
- Department of Chemistry, University of Massachusetts , LGRT 104, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| |
Collapse
|
49
|
Roy S, Banerjee V, Das KP. Understanding the Physical and Molecular Basis of Stability of Arabidopsis DNA Pol λ under UV-B and High NaCl Stress. PLoS One 2015; 10:e0133843. [PMID: 26230318 PMCID: PMC4521722 DOI: 10.1371/journal.pone.0133843] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 07/02/2015] [Indexed: 01/27/2023] Open
Abstract
Here, we have investigated the physical and molecular basis of stability of Arabidopsis DNA Pol λ, the sole X family DNA polymerase member in plant genome, under UV-B and salinity stress in connection with the function of the N-terminal BRCT (breast cancer-associated C terminus) domain and Ser-Pro rich region in the regulation of the overall structure of this protein. Tryptophan fluorescence studies, fluorescence quenching and Bis-ANS binding experiments using purified recombinant full length Pol λ and its N-terminal deletion forms have revealed UV-B induced conformational change in BRCT domain deficient Pol λ. On the other hand, the highly conserved C-terminal catalytic core PolX domain maintained its tertiary folds under similar condition. Circular dichroism (CD) and fourier transform infrared (FT-IR) spectral studies have indicated appreciable change in the secondary structural elements in UV-B exposed BRCT domain deficient Pol λ. Increased thermodynamic stability of the C-terminal catalytic core domain suggested destabilizing effect of the N-terminal Ser-Pro rich region on the protein structure. Urea-induced equilibrium unfolding studies have revealed increased stability of Pol λ and its N-terminal deletion mutants at high NaCl concentration. In vivo aggregation studies using transient expression systems in Arabidopsis and tobacco indicated possible aggregation of Pol λ lacking the BRCT domain. Immunoprecipitation assays revealed interaction of Pol λ with the eukaryotic molecular chaperone HSP90, suggesting the possibility of regulation of Pol λ stability by HSP90 in plant cell. Overall, our results have provided one of the first comprehensive information on the biophysical characteristics of Pol λ and indicated the importance of both BRCT and Ser-Pro rich modules in regulating the stability of this protein under genotoxic stress in plants.
Collapse
Affiliation(s)
- Sujit Roy
- Protein Chemistry laboratory, Department of Chemistry, Bose Institute, Kolkata, West Bengal, India
- * E-mail:
| | - Victor Banerjee
- Protein Chemistry laboratory, Department of Chemistry, Bose Institute, Kolkata, West Bengal, India
| | - Kali Pada Das
- Protein Chemistry laboratory, Department of Chemistry, Bose Institute, Kolkata, West Bengal, India
| |
Collapse
|
50
|
Zare D, McGrath KM, Allison JR. Deciphering β-Lactoglobulin Interactions at an Oil-Water Interface: A Molecular Dynamics Study. Biomacromolecules 2015; 16:1855-61. [PMID: 25989152 DOI: 10.1021/acs.biomac.5b00467] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein adsorption at liquid-liquid interfaces is of immense relevance to many biological processes and dairy-based functional foods. Due to experimental limitations, however, there is still a remarkable lack of understanding of the adsorption mechanism, particularly at a molecular level. In this study, atomistic molecular dynamics simulations were used to elucidate the approach and adsorption mechanism of β-lactoglobulin (β-LG) at a decane-water interface. Through multiple independent simulations starting from three representative initial orientations of β-LG relative to the decane surface the rate at which β-LG approaches the oil/water interface is found to be independent of its initial orientation, and largely stochastic in nature. While the residues that first make contact with the decane and the final orientation of β-LG upon adsorption are similar in all cases, the adsorption process is driven predominantly by structural rearrangements that preserve the secondary structure but expose hydrophobic residues to the decane surface. This detailed characterization of the adsorption of β-LG at an oil/water interface should inform the design and development of novel encapsulation and delivery systems in the food and pharmaceutical sciences.
Collapse
Affiliation(s)
- Davoud Zare
- †MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand.,‡Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
| | - Kathryn M McGrath
- †MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Chemical and Physical Sciences, Victoria University of Wellington, P.O. Box 600, Wellington 6140, New Zealand.,‡Riddet Institute, Massey University, Private Bag 11 222, Palmerston North 4442, New Zealand
| | - Jane R Allison
- §Centre for Theoretical Chemistry and Physics, Institute of Natural and Mathematical Sciences, Massey University Auckland, Albany, Auckland 0632, New Zealand.,∥Biomolecular Interaction Centre, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.,⊥Maurice Wilkins Centre for Molecular Biodiscovery, University of Auckland, Private Bag 92019, Auckland, New Zealand
| |
Collapse
|