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Bhattacharjee S, Pandit S, Seth D. Co-Solutes Induced Changes in the Properties of Polymeric Solution and Water Dynamics. Chemphyschem 2024; 25:e202400236. [PMID: 38517663 DOI: 10.1002/cphc.202400236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 03/24/2024]
Abstract
In this paper we are addressing the co-solute-induced changes in the properties of an aqueous solution of a block copolymer. Due to the preferential interaction of different co-solute with different regions of the block copolymer, the changes were observed in both the physical properties and water dynamics. The modulation of both the physical properties and water dynamics was monitored using different spectroscopic techniques. Different co-solutes affect micellar properties of copolymer to a different extent signifying their interactions with different regions within the copolymer. The solvent relaxation dynamics were also modulated with the additions of different co-solutes. The change in free-energy (ΔGbf) and rate constant for bound to free water interconversion (kbf) in a copolymeric micelle was calculated which gets affected by the addition of co-solutes. The calculated kbf suggests that betaine, sarcosine, TMAO, and GnHCl favor the ordering of water molecules around the micelle and are excluded from the micellar surface whereas, urea favors the formation of free-water molecules rather than the structurally ordered bound water molecules around the micelle by accumulating at the micellar surface. Among the added methylamines trimethylamine N-oxide affected the water dynamics and its kinetics most profoundly. The protective property of GnHCl was revealed.
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Affiliation(s)
- Sanyukta Bhattacharjee
- Department of Chemistry, Indian Institute of Technology Patna, Patna, 801103, Bihar, India
| | - Souvik Pandit
- Department of Chemistry, Indian Institute of Technology Patna, Patna, 801103, Bihar, India
| | - Debabrata Seth
- Department of Chemistry, Indian Institute of Technology Patna, Patna, 801103, Bihar, India
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2
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Arar S, Haque MA, Bhatt N, Zhao Y, Kayed R. Effect of Natural Osmolytes on Recombinant Tau Monomer: Propensity of Oligomerization and Aggregation. ACS Chem Neurosci 2024; 15:1366-1377. [PMID: 38503425 PMCID: PMC10995947 DOI: 10.1021/acschemneuro.3c00614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 02/19/2024] [Accepted: 02/20/2024] [Indexed: 03/21/2024] Open
Abstract
The pathological misfolding and aggregation of the microtubule associated protein tau (MAPT), a full length Tau2N4R with 441aa, is considered the principal disease relevant constituent in tauopathies including Alzheimer's disease (AD) with an imbalanced ratio in 3R/4R isoforms. The exact cellular fluid composition, properties, and changes that coincide with tau misfolding, seed formation, and propagation events remain obscure. The proteostasis network, along with the associated osmolytes, is responsible for maintaining the presence of tau in its native structure or dealing with misfolding. In this study, for the first time, the roles of natural brain osmolytes are being investigated for their potential effects on regulating the conformational stability of the tau monomer (tauM) and its propensity to aggregate or disaggregate. Herein, the effects of physiological osmolytes myo-inositol, taurine, trimethyl amine oxide (TMAO), betaine, sorbitol, glycerophosphocholine (GPC), and citrulline on tau's aggregation state were investigated. The overall results indicate the ability of sorbitol and GPC to maintain the monomeric form and prevent aggregation of tau, whereas myo-inositol, taurine, TMAO, betaine, and citrulline promote tau aggregation to different degrees, as revealed by protein morphology in atomic force microscopy images. Biochemical and biophysical methods also revealed that tau proteins adopt different conformations under the influence of these osmolytes. TauM in the presence of all osmolytes expressed no toxicity when tested by a lactate dehydrogenase assay. Investigating the conformational stability of tau in the presence of osmolytes may provide a better understanding of the complex nature of tau aggregation in AD and the protective and/or chaotropic nature of osmolytes.
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Affiliation(s)
- Sharif Arar
- Mitchell
Center for Neurodegenerative Diseases, University
of Texas Medical Branch, Galveston, Texas 77555, United States
- Departments
of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, United States
- Department
of Chemistry, School of Science, The University
of Jordan, Amman 11942, Jordan
| | - Md Anzarul Haque
- Mitchell
Center for Neurodegenerative Diseases, University
of Texas Medical Branch, Galveston, Texas 77555, United States
- Departments
of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Nemil Bhatt
- Mitchell
Center for Neurodegenerative Diseases, University
of Texas Medical Branch, Galveston, Texas 77555, United States
- Departments
of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Yingxin Zhao
- Department
of Internal Medicine, University of Texas
Medical Branch, Galveston, Texas 77555, United States
- Institute
for Translational Sciences, University of
Texas Medical Branch, Galveston, Texas 77555, United States
| | - Rakez Kayed
- Mitchell
Center for Neurodegenerative Diseases, University
of Texas Medical Branch, Galveston, Texas 77555, United States
- Departments
of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, United States
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3
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Nasralla M, Laurent H, Alderman OLG, Headen TF, Dougan L. Trimethylamine-N-oxide depletes urea in a peptide solvation shell. Proc Natl Acad Sci U S A 2024; 121:e2317825121. [PMID: 38536756 PMCID: PMC10998561 DOI: 10.1073/pnas.2317825121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 02/15/2024] [Indexed: 04/08/2024] Open
Abstract
Trimethylamine-N-oxide (TMAO) and urea are metabolites that are used by some marine animals to maintain their cell volume in a saline environment. Urea is a well-known denaturant, and TMAO is a protective osmolyte that counteracts urea-induced protein denaturation. TMAO also has a general protein-protective effect, for example, it counters pressure-induced protein denaturation in deep-sea fish. These opposing effects on protein stability have been linked to the spatial relationship of TMAO, urea, and protein molecules. It is generally accepted that urea-induced denaturation proceeds through the accumulation of urea at the protein surface and their subsequent interaction. In contrast, it has been suggested that TMAO's protein-stabilizing effects stem from its exclusion from the protein surface, and its ability to deplete urea from protein surfaces; however, these spatial relationships are uncertain. We used neutron diffraction, coupled with structural refinement modeling, to study the spatial associations of TMAO and urea with the tripeptide derivative glycine-proline-glycinamide in aqueous urea, aqueous TMAO, and aqueous urea-TMAO (in the mole ratio 1:2 TMAO:urea). We found that TMAO depleted urea from the peptide's surface and that while TMAO was not excluded from the tripeptide's surface, strong atomic interactions between the peptide and TMAO were limited to hydrogen bond donating peptide groups. We found that the repartition of urea, by TMAO, was associated with preferential TMAO-urea bonding and enhanced urea-water hydrogen bonding, thereby anchoring urea in the bulk solution and depleting urea from the peptide surface.
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Affiliation(s)
- Mazin Nasralla
- School of Physics and Astronomy, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Harrison Laurent
- School of Physics and Astronomy, University of Leeds, LeedsLS2 9JT, United Kingdom
| | - Oliver L. G. Alderman
- Disordered Materials Group, ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, DidcotOX11 0QX, United Kingdom
| | - Thomas F. Headen
- Disordered Materials Group, ISIS Neutron and Muon Source, Rutherford Appleton Laboratory, DidcotOX11 0QX, United Kingdom
| | - Lorna Dougan
- School of Physics and Astronomy, University of Leeds, LeedsLS2 9JT, United Kingdom
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4
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Chaudhuri D, Chowdhury D, Chakraborty S, Bhatt M, Chowdhury R, Dutta A, Mistry A, Haldar S. Structurally different chemical chaperones show similar mechanical roles with independent molecular mechanisms. NANOSCALE 2024; 16:2540-2551. [PMID: 38214221 DOI: 10.1039/d3nr00398a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Osmolytes are well known to protect the protein structure against different chemical and physical denaturants. Since their actions with protein surfaces are mechanistically complicated and context dependent, the underlying molecular mechanism is not fully understood. Here, we combined single-molecule magnetic tweezers and molecular dynamics (MD) simulation to explore the mechanical role of osmolytes from two different classes, trimethylamine N-oxide (TMAO) and trehalose, as mechanical stabilizers of protein structure. We observed that these osmolytes increase the protein L mechanical stability by decreasing unfolding kinetics while accelerating the refolding kinetics under force, eventually shifting the energy landscape toward the folded state. These osmolytes mechanically stabilize the protein L and plausibly guide them to more thermodynamically robust states. Finally, we observed that osmolyte-modulated protein folding increases mechanical work output up to twofold, allowing the protein to fold under a higher force regime and providing a significant implication for folding-induced structural stability in proteins.
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Affiliation(s)
- Deep Chaudhuri
- Department of Chemistry, Ashoka University, Sonepat, Haryana, India.
| | - Debojyoti Chowdhury
- Department of Chemical and Biological Sciences, S.N. Bose National Center for Basic Sciences, Kolkata, West Bengal, India
| | - Soham Chakraborty
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India
| | - Madhu Bhatt
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India
| | - Rudranil Chowdhury
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India
| | - Aakashdeep Dutta
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India
| | - Ayush Mistry
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India
| | - Shubhasis Haldar
- Department of Chemistry, Ashoka University, Sonepat, Haryana, India.
- Department of Chemical and Biological Sciences, S.N. Bose National Center for Basic Sciences, Kolkata, West Bengal, India
- Department of Biology, Trivedi School of Biosciences, Ashoka University, Sonepat, Haryana, India
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5
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Bajaj M, Muddassir M, Choi B, Singh P, Park JB, Singh S, Yadav M, Kumar R, Eom K, Sharma D. Single-molecule analysis of osmolyte-mediated nanomechanical unfolding behavior of a protein domain. Int J Biol Macromol 2023; 253:126849. [PMID: 37717878 DOI: 10.1016/j.ijbiomac.2023.126849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 08/25/2023] [Accepted: 09/09/2023] [Indexed: 09/19/2023]
Abstract
The small organic molecules, known as osmolytes being ubiquitously present in different cell types, affect protein folding, stability and aggregation. However, it is unknown how the osmolytes affect the nanomechanical unfolding behavior of protein domain. Here, we show the osmolyte-dependent mechanical unfolding properties of protein titin immunoglobulin-27 (I27) domain using an atomic force microscopy (AFM)-based single-molecule force spectroscopy. We found that amines and methylamines improved the mechanical stability of I27 domain, whereas polyols had no effect. Interestingly, glycine betaine (GB) or trimethylamine-N-oxide (TMAO) increased the average unfolding force of the protein domain. The kinetic parameters analyzed at single-molecule level reveal that stabilizing effect of osmolytes is due to a decrease in the unfolding rate constant of I27, which was confirmed by molecular dynamics simulations. Our study reveals different effects that diverse osmolytes have on the mechanical properties of the protein, and suggests the potential use of osmolytes in modulating the mechanical stability of proteins required for various nano-biotechnological applications.
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Affiliation(s)
- Manish Bajaj
- Council of Scientific and Industrial Research - Institute of Microbial Technology, Sector-39A, Chandigarh, India
| | - Mohd Muddassir
- Council of Scientific and Industrial Research - Institute of Microbial Technology, Sector-39A, Chandigarh, India; Department of Chemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Bumjoon Choi
- Biomechanics Laboratory, College of Sport Science, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea; Digial Bio R&D Center, Mediazen, Seoul 07789, Republic of Korea
| | - Priyanka Singh
- Council of Scientific and Industrial Research - Institute of Microbial Technology, Sector-39A, Chandigarh, India
| | - Jong Bum Park
- Biomechanics Laboratory, College of Sport Science, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - Surjeet Singh
- Council of Scientific and Industrial Research - Institute of Microbial Technology, Sector-39A, Chandigarh, India
| | - Manisha Yadav
- School of Basic and Applied Sciences, Central University of Punjab, Bathinda, India
| | - Rajesh Kumar
- School of Basic and Applied Sciences, Central University of Punjab, Bathinda, India
| | - Kilho Eom
- Biomechanics Laboratory, College of Sport Science, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea.
| | - Deepak Sharma
- Council of Scientific and Industrial Research - Institute of Microbial Technology, Sector-39A, Chandigarh, India; Academy of Scientific & Innovative Research, India.
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6
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Sarkar S, Narayanan TN, Mondal J. A Synergistic View on Osmolyte's Role against Salt and Cold Stress in Biointerfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:17581-17592. [PMID: 38044584 DOI: 10.1021/acs.langmuir.3c02397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
We present our perspective on the role of osmolytes in mitigating abiotic stresses such as hypersalinity and sudden temperature changes. While the stabilizing effect of osmolytes on protein tertiary structures has been extensively studied, their direct impact on abiotic stress factors has eluded mainstream attention. Via highlighting a set of recent success stories of a joint venture of computer simulations and experimental measurements, we summarize the mechanistic insights into osmolytic action, particularly in the context of salt stress and combined cold-salt stress at the interface of biomolecular surfaces and saline environments. We stress the importance of chemical specificity in osmolytic activity, the interplay of differential osmolytic behaviors against heterogeneous salt stress, and the capability of osmolytes to adopt combined actions. Additionally, we discuss the potential of incorporating nanomaterial-based systems to enrich our understanding of osmolyte bioactions and facilitate their practical applications. We anticipate that this discourse will inspire interdisciplinary collaborations and motivate further investigations on osmolytes, ultimately broadening their applications in the fields of health and disease.
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Affiliation(s)
- Susmita Sarkar
- Tata Institute of Fundamental Research Hyderabad, Hyderabad 500046, India
| | | | - Jagannath Mondal
- Tata Institute of Fundamental Research Hyderabad, Hyderabad 500046, India
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7
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Sarkar S, Guha A, Sadhukhan R, Narayanan TN, Mondal J. Osmolytes as Cryoprotectants under Salt Stress. ACS Biomater Sci Eng 2023; 9:5639-5652. [PMID: 37697623 DOI: 10.1021/acsbiomaterials.3c00763] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Cryoprotecting agent (CPA)-guided preservation is essential for effective protection of cells from cryoinjuries. However, current cryoprotecting technologies practiced to cryopreserve cells for biomedical applications are met with extreme challenges due to the associated toxicity of CPAs. Because of these limitations of present CPAs, the quest for nontoxic alternatives for useful application in cell-based biomedicines has been attracting growing interest. Toward this end, here, we investigate naturally occurring osmolytes' scope as biocompatible cryoprotectants under cold stress conditions in high-saline medium. Via a combination of the simulation and experiment on charged silica nanostructures, we render first-hand evidence that a pair of archetypal osmolytes, glycine and betaine, would act as a cryoprotectant by restoring the indigenous intersurface electrostatic interaction, which had been a priori screened due to the cold effect under salt stress. While these osmolytes' individual modes of action are sensitive to subtle chemical variation, a uniform augmentation in the extent of osmolytic activity is observed with an increase in temperature to counter the proportionately enhanced salt screening. The trend as noted in inorganic nanostructures is found to be recurrent and robustly transferable in a charged protein interface. In hindsight, our observation justifies the sufficiency of the reduced requirement of osmolytes in cells during critical cold conditions and encourages their direct usage and biomimicry for cryopreservation.
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Affiliation(s)
- Susmita Sarkar
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
| | - Anku Guha
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
| | - Rayantan Sadhukhan
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
| | - Tharangattu N Narayanan
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
| | - Jagannath Mondal
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
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8
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Folberth A, van der Vegt NFA. Influence of TMAO and Pressure on the Folding Equilibrium of TrpCage. J Phys Chem B 2022; 126:8374-8380. [PMID: 36251479 DOI: 10.1021/acs.jpcb.2c04034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Trimethylamine-N-oxide (TMAO) is an osmolyte known for its ability to counteract the pressure denaturation of proteins. Computational studies addressing the molecular mechanisms of TMAO's osmolyte action have however focused exclusively on its protein-stabilizing properties at ambient pressure, neglecting the changes that may occur under high-pressure conditions where TMAO's hydration structure changes to that of increased water binding. Here, we present the first study on the combined effect of pressure and TMAO on a mini-protein, TrpCage. The results showed that at high pressures, nonpolar residues packed less tightly and the salt bridge of TrpCage was destabilized. This effect was mitigated by TMAO which was found to be strongly depleted from the protein/water interface at 1 kbar than at 1 bar ambient pressure, thus counterbalancing the thermodynamically unfavorable effect of elevated pressure in the free energy of folding. TMAO was depleted from charged groups, like the salt bridge-forming ones, and accumulated around hydrophobic groups. Still, it stabilized both kinds of interactions. Furthermore, enthalpically favorable TrpCage-water hydrogen bonds were reduced in the presence of TMAO, causing a stronger destabilization of the unfolded state than the folded state. This shifted the protein-folding equilibrium toward the folded state. Therefore, TMAO showed stabilizing effects on different kinds of groups, which were partially enhanced at high pressures.
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Affiliation(s)
- Angelina Folberth
- Eduard-Zintl-Institut Fuer Anorganische und Physikalische Chemie, Technical University of Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
| | - Nico F A van der Vegt
- Eduard-Zintl-Institut Fuer Anorganische und Physikalische Chemie, Technical University of Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
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9
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Crescenzi O, Graziano G. A quantum chemical study on the hydration energetics of trimethylamine N-oxide, its protonated form and tert-butanol. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.139905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Ganguly P, Bubák D, Polák J, Fagan P, Dračínský M, van der Vegt NFA, Heyda J, Shea JE. Cosolvent Exclusion Drives Protein Stability in Trimethylamine N-Oxide and Betaine Solutions. J Phys Chem Lett 2022; 13:7980-7986. [PMID: 35984361 DOI: 10.1021/acs.jpclett.2c01692] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Using a combination of molecular dynamics simulation, dialysis experiments, and electronic circular dichroism measurements, we studied the solvation thermodynamics of proteins in two osmolyte solutions, trimethylamine N-oxide (TMAO) and betaine. We showed that existing force fields are unable to capture the solvation properties of the proteins lysozyme and ribonuclease T1 and that the inaccurate parametrization of protein-osmolyte interactions in these force fields promoted an unphysical strong thermal denaturation of the trpcage protein. We developed a novel force field for betaine (the KBB force field) which reproduces the experimental solution Kirkwood-Buff integrals and density. We further introduced appropriate scaling to protein-osmolyte interactions in both the betaine and TMAO force fields which led to successful reproduction of experimental protein-osmolyte preferential binding coefficients for lysozyme and ribonuclease T1 and prevention of the unphysical denaturation of trpcage in osmolyte solutions. Correct parametrization of protein-TMAO interactions also led to the stabilization of the collapsed conformations of a disordered elastin-like peptide, while the uncorrected parameters destabilized the collapsed structures. Our results establish that the thermodynamic stability of proteins in both betaine and TMAO solutions is governed by osmolyte exclusion from proteins.
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Affiliation(s)
- Pritam Ganguly
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California93106, United States
| | - Dominik Bubák
- Department of Physical Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28Prague 6, Czech Republic
| | - Jakub Polák
- Department of Physical Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28Prague 6, Czech Republic
| | - Patrik Fagan
- Department of Analytical Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28Prague 6, Czech Republic
| | - Martin Dračínský
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Flemingovo nám. 2, 160 00Prague, Czech Republic
| | - Nico F A van der Vegt
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 10, Darmstadt64287, Germany
| | - Jan Heyda
- Department of Physical Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28Prague 6, Czech Republic
| | - Joan-Emma Shea
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California93106, United States
- Department of Physics, University of California at Santa Barbara, Santa Barbara, California93106, United States
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11
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Monhemi H, Hoang HN, Standley DM, Matsuda T, Housaindokht MR. The protein-stabilizing effects of TMAO in aqueous and non-aqueous conditions. Phys Chem Chem Phys 2022; 24:21178-21187. [PMID: 36039911 DOI: 10.1039/d2cp01279k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a new water-dependent molecular mechanism for the widely-used protein stabilizing osmolyte, trimethylamine N-oxide (TMAO), whose mode of action has remained controversial. Classical interpretations, such as osmolyte exclusion from the vicinity of protein, cannot adequately explain the behavior of this osmolyte and were challenged by recent data showing the direct interactions of TMAO with proteins, mainly via hydrophobic binding. Solvent effect theories also fail to propose a straightforward mechanism. To explore the role of water and the hydrophobic association, we disabled osmolyte-protein hydrophobic interactions by replacing water with hexane and using lipase enzyme as an anhydrous-stable protein. Biocatalysis experiments showed that under this non-aqueous condition, TMAO does not act as a stabilizer, but strongly deactivates the enzyme. Molecular dynamics (MD) simulations reveal that TMAO accumulates near the enzyme and makes many hydrogen bonds with it, like denaturing osmolytes. Some TMAO molecules even reach the active site and interact strongly with the catalystic traid. In aqueous solvent, the enzyme functions well: the extent of TMAO interactions is reduced and can be divided into both polar and non-polar terms. Structural analysis shows that in water, some TMAO molecules bind to the enzyme surface like a surfactant. We show that these interactions limit water-protein hydrogen bonds and unfavorable water-hydrophobic surface contacts. Moreover, a more hydrophobic environment is formed in the solvation layer, which reduces water dynamics and subsequently, rigidifies the backbone in aqueous solution. We show that osmolyte amphiphilicity and protein surface heterogeneity can address the weaknesses of exclusion and solvent effect theories about the TMAO mechanism.
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Affiliation(s)
- Hassan Monhemi
- Department of Chemistry, University of Neyshabur, Neyshabur, Iran. .,Research and Technology Center of Biomolecules, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | - Hai Nam Hoang
- Department of Food Technology, Faculty of Chemical Engineering, Ho Chi Minh City University of Technology (HCMUT), 268 Ly Thuong Kiet Street, District 10, Ho Chi Minh City, Vietnam.,Vietnam National University Ho Chi Minh City, Linh Trung Ward, Thu Duc District, Ho Chi Minh City, Vietnam
| | - Daron M Standley
- Laboratory of Systems Immunology, WPI Immunology Frontier Research Center Osaka University, Osaka 565-0871, Japan
| | - Tomoko Matsuda
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Mohammad Reza Housaindokht
- Research and Technology Center of Biomolecules, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
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12
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TMAO to the rescue of pathogenic protein variants. Biochim Biophys Acta Gen Subj 2022; 1866:130214. [PMID: 35902028 DOI: 10.1016/j.bbagen.2022.130214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 07/11/2022] [Accepted: 07/21/2022] [Indexed: 11/22/2022]
Abstract
Trimethylamine N-oxide (TMAO) is a chemical chaperone found in various organisms including humans. Various studies unveiled that it is an excellent protein-stabilizing agent, and induces folding of unstructured proteins. It is also well established that it can counteract the deleterious effects of urea, salt, and hydrostatic pressure on macromolecular integrity. There is also existence of large body of data regarding its ability to restore functional deficiency of various mutant proteins or pathogenic variants by correcting misfolding defects and inhibiting the formation of high-order toxic protein oligomers. Since an important class of human disease called "protein conformational disorders" is due to protein misfolding and/or formation of high-order oligomers, TMAO stands as a promising molecule for the therapeutic intervention of such diseases. The present review has been designed to gather a comprehensive knowledge of the TMAO's effect on the functional restoration of various mutants, identify its shortcomings and explore its potentiality as a lead molecule. Future prospects have also been suitably incorporated.
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13
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Liu Z, Lan Y, Jia J, Geng Y, Dai X, Yan L, Hu T, Chen J, Matyjaszewski K, Ye G. Multi-scale computer-aided design and photo-controlled macromolecular synthesis boosting uranium harvesting from seawater. Nat Commun 2022; 13:3918. [PMID: 35798729 PMCID: PMC9262957 DOI: 10.1038/s41467-022-31360-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 06/15/2022] [Indexed: 11/09/2022] Open
Abstract
By integrating multi-scale computational simulation with photo-regulated macromolecular synthesis, this study presents a new paradigm for smart design while customizing polymeric adsorbents for uranium harvesting from seawater. A dissipative particle dynamics (DPD) approach, combined with a molecular dynamics (MD) study, is performed to simulate the conformational dynamics and adsorption process of a model uranium grabber, i.e., PAOm-b-PPEGMAn, suggesting that the maximum adsorption capacity with atomic economy can be achieved with a preferred block ratio of 0.18. The designed polymers are synthesized using the PET-RAFT polymerization in a microfluidic platform, exhibiting a record high adsorption capacity of uranium (11.4 ± 1.2 mg/g) in real seawater within 28 days. This study offers an integrated perspective to quantitatively assess adsorption phenomena of polymers, bridging metal-ligand interactions at the molecular level with their spatial conformations at the mesoscopic level. The established protocol is generally adaptable for target-oriented development of more advanced polymers for broadened applications. Developing materials for uranium harvesting from seawater with high adsorption capacity remains challenging. Here, the authors develop a new protocol, by combining multi-scale computational simulations with the PET-RAFT polymerization, for rational design and precise synthesis of block copolymers with optimal architectures and atomic economy, achieving a capacity of 11.4 mg/g within 28 days.
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Affiliation(s)
- Zeyu Liu
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Youshi Lan
- China Institute of Atomic Energy, Department of Radiochemistry, 102413, Beijing, People's Republic of China
| | - Jianfeng Jia
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Yiyun Geng
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Xiaobin Dai
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Litang Yan
- State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Tongyang Hu
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Jing Chen
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, People's Republic of China
| | - Krzysztof Matyjaszewski
- Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA.
| | - Gang Ye
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, People's Republic of China.
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14
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Kamali A, Jahmidi-Azizi N, Oliva R, Winter R. Deep sea osmolytes in action: their effect on protein-ligand binding under high pressure stress. Phys Chem Chem Phys 2022; 24:17966-17978. [PMID: 35775876 DOI: 10.1039/d2cp01769e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Because organisms living in the deep sea and in the sub-seafloor must be able to cope with hydrostatic pressures up to 1000 bar and more, their biomolecular processes, including ligand-binding reactions, must be adjusted to keep the associated volume changes low in order to function efficiently. Almost all organisms use organic cosolvents (osmolytes) to protect their cells from adverse environmental conditions. They counteract osmotic imbalance, stabilize the structure of proteins and maintain their function. We studied the binding properties of the prototypical ligand proflavine to two serum proteins with different binding pockets, BSA and HSA, in the presence of two prominent osmolytes, trimethylamine-N-oxide (TMAO) and glycine betaine (GB). TMAO and GB play an important role in the regulation and adaptation of life in deep-sea organisms. To this end, pressure dependent fluorescence spectroscopy was applied, supplemented by circular dichroism (CD) spectroscopy and computer modeling studies. The pressure-dependent measurements were also performed to investigate the intimate nature of the complex formation in relation to hydration and packing changes caused by the presence of the osmolytes. We show that TMAO and GB are able to modulate the ligand binding process in specific ways. Depending on the chemical make-up of the protein's binding pocket and thus the thermodynamic forces driving the binding process, there are osmolytes with specific interaction sites and binding strengths with water that are able to mediate efficient ligand binding even under external stress conditions. In the binding of proflavine to BSA and HSA, the addition of both compatible osmolytes leads to an increase in the binding constant upon pressurization, with TMAO being the most efficient, rendering the binding process also insensitive to pressurization even up to 2 kbar as the volume change remains close to zero. This effect can be corroborated by the effects the cosolvents impose on the strength and dynamics of hydration water as well as on the conformational dynamics of the protein.
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Affiliation(s)
- Armin Kamali
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany.
| | - Nisrine Jahmidi-Azizi
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany.
| | - Rosario Oliva
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, 80126 Naples, Italy.
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Street 4a, 44227 Dortmund, Germany.
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15
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Sarkar S, Guha A, Narayanan TN, Mondal J. Zwitterionic Osmolytes Revive Surface Charges under Salt Stress via Dual Mechanisms. J Phys Chem Lett 2022; 13:5660-5668. [PMID: 35709362 DOI: 10.1021/acs.jpclett.2c00853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
To counter the stress of a salt imbalance, the cell often produces low molecular weight osmolytes to resuscitate homeostasis. However, how zwitterionic osmolytes would tune the electrostatic interactions among charged biomacromolecular surfaces under salt stress has eluded mainstream investigations. Here, via combination of molecular simulation and experiment, we demonstrate that a set of zwitterionic osmolytes is able to restore the electrostatic interaction between two negatively charged surfaces that had been masked in the presence of salt. Interestingly, the mechanisms of resurrecting charge interaction under excess salt are revealed to be mutually divergent and osmolyte specific. In particular, glycine is found to competitively desorb the salt ions from the surface via its direct interaction with the surface. On the contrary, TMAO and betaine counteract salt stress by retaining adsorbed cations but partially neutralizing their charge density via ion-mediated interaction. These access to alternative modes of osmolytic actions would provide the cell the required flexibility in combating salt stress.
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Affiliation(s)
- Susmita Sarkar
- Tata Institute of Fundamental Research, Hyderabad500046, India
| | - Anku Guha
- Tata Institute of Fundamental Research, Hyderabad500046, India
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16
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Folberth A, van der Vegt NFA. Temperature induced change of TMAO effects on hydrophobic hydration. J Chem Phys 2022; 156:184501. [DOI: 10.1063/5.0088388] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The effect of trimethylamine-N-oxide (TMAO) on hydrophobic solvation and hydrophobic interactions of methane has been studied with Molecular Dynamics simulations in the temperature range between 280 and 370 K at 1 bar ambient pressure. We observe a temperature transition in the effect of TMAO on the aqueous solubility of methane. At low temperature (280 K), methane is preferentially hydrated, causing TMAO to reduce its solubility in water, while above 320 K, methane preferentially interacts with TMAO, causing TMAO to promote its solubility in water. Based on a statistical-mechanical analysis of the excess chemical potential of methane, we find that the reversible work of creating a repulsive methane cavity opposes the solubility of methane in TMAO/water solution more than in pure water. Below 320 K, this solvent-excluded volume effect overcompensates the contribution of methane–TMAO van der Waals interactions, which promote the solvation of methane and are observed at all temperatures. These van der Waals interactions with the methyl groups of TMAO tip the balance above 320 K where the effect of TMAO on solvent-excluded volume is smaller. We furthermore find that the effective attraction between dissolved methane solutes increases with the increasing TMAO concentration. This observation correlates with a reduction in the methane solubility below 320 K but with an increase in methane solubility at higher temperatures.
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Affiliation(s)
- Angelina Folberth
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Nico F. A. van der Vegt
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
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17
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Bharadwaj S, Niebuur BJ, Nothdurft K, Richtering W, van der Vegt NFA, Papadakis CM. Cononsolvency of thermoresponsive polymers: where we are now and where we are going. SOFT MATTER 2022; 18:2884-2909. [PMID: 35311857 DOI: 10.1039/d2sm00146b] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cononsolvency is an intriguing phenomenon where a polymer collapses in a mixture of good solvents. This cosolvent-induced modulation of the polymer solubility has been observed in solutions of several polymers and biomacromolecules, and finds application in areas such as hydrogel actuators, drug delivery, compound detection and catalysis. In the past decade, there has been a renewed interest in understanding the molecular mechanisms which drive cononsolvency with a predominant emphasis on its connection to the preferential adsorption of the cosolvent. Significant efforts have also been made to understand cononsolvency in complex systems such as micelles, block copolymers and thin films. In this review, we will discuss some of the recent developments from the experimental, simulation and theoretical fronts, and provide an outlook on the problems and challenges which are yet to be addressed.
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Affiliation(s)
- Swaminath Bharadwaj
- Technical University of Darmstadt, Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Computational Physical Chemistry Group, 64287 Darmstadt, Germany.
| | - Bart-Jan Niebuur
- Technical University of Munich, Physics Department, Soft Matter Physics Group, James-Franck-Str. 1, 85748 Garching, Germany
| | - Katja Nothdurft
- RWTH Aachen University, Institut für Physikalische Chemie, Landoltweg 2, 52056 Aachen, Germany, European Union
| | - Walter Richtering
- RWTH Aachen University, Institut für Physikalische Chemie, Landoltweg 2, 52056 Aachen, Germany, European Union
| | - Nico F A van der Vegt
- Technical University of Darmstadt, Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Computational Physical Chemistry Group, 64287 Darmstadt, Germany.
| | - Christine M Papadakis
- Technical University of Munich, Physics Department, Soft Matter Physics Group, James-Franck-Str. 1, 85748 Garching, Germany
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18
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Hajari T, Dixit M, Yadav HOS. Hydrophobic association and solvation of neopentane in urea, TMAO and urea-TMAO solutions. Phys Chem Chem Phys 2022; 24:6941-6957. [PMID: 35254354 DOI: 10.1039/d1cp05321c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A detailed knowledge of hydrophobic association and solvation is crucial for understanding the con-formational stability of proteins and polymers in osmolyte solutions. Using molecular dynamics simulations, it is found that the hydrophobic association of neopentane molecules is greater in a mixed urea-TMAO-water solution in comparison to that in 8 M urea solution, 4 M TMAO solution and neat water. The neopentane association in urea solution is greater than that in TMAO solution or neat water. We find the association is even less in TMAO solution than pure water. From free energy calculations, it is revealed that the neopentane sized cavity creation in mixed urea-TMAO-water is most unfavorable and that causes the highest hydrophobic association. The cavity formation in urea solution is either more unfavorable or comparable to that in TMAO solution. Importantly, it is found that the population of neopentane-neopentane contact pair and the free energy contribution for the cavity formation step in TMAO solution are very sensitive towards the choice of TMAO force-fields. A careful construction of TMAO force-fields is important for studying the hydrophobic association. Interestingly it is observed that the total solute-solvent dispersion interaction energy contribution is always the most favorable in mixed urea-TMAO-water. The magnitude of this interaction energy is greater in urea solution relative to TMAO solution for two different force-fields of TMAO, whereas the lowest value is obtained in pure water. It is revealed that the extent of the overall hydrophobic association in osmolyte solutions is mainly governed by the cavity creation step and it nullifies the contribution coming from the solute-solvent interaction contribution.
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Affiliation(s)
- Timir Hajari
- Department of Chemistry, City College, 102/1, Raja Rammohan Sarani, Kolkata - 700 009, India.
| | - Mayank Dixit
- Graduate School of Engineering, Department of Chemical Engineering Kyoto University-Katsura Nishikyo-ku, Kyoto-Shi, Kyoto-fu, 615-8510, Japan.
| | - Hari O S Yadav
- Department of Materials Chemistry, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan.
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19
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Cinar H, Oliva R, Wu H, Zhang M, Chan HS, Winter R. Effects of Cosolvents and Crowding Agents on the Stability and Phase Transition Kinetics of the SynGAP/PSD-95 Condensate Model of Postsynaptic Densities. J Phys Chem B 2022; 126:1734-1741. [PMID: 35171623 DOI: 10.1021/acs.jpcb.2c00794] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The SynGAP/PSD-95 binary protein system serves as a simple mimicry of postsynaptic densities (PSDs), which are protein assemblies based largely on liquid-liquid phase separation (LLPS), that are located underneath the plasma membrane of excitatory synapses. Surprisingly, the LLPS of the SynGAP/PSD-95 system is much more pressure sensitive than typical folded states of proteins or nucleic acids. It was found that phase-separated SynGAP/PSD-95 droplets dissolve into a homogeneous solution at a pressure of tens to hundred bar. Since organisms in the deep sea are exposed to pressures of up to ∼1000 bar, this observation suggests that deep-sea organisms must counteract the high pressure sensitivity of PSDs to avoid neurological impairment. We demonstrate here that the compatible osmolyte trimethylamine-N-oxide (TMAO) as well as macromolecular crowding agents at moderate concentrations can mitigate the deleterious effect of pressure on SynGAP/PSD-95 droplet stability, extending stable LLPS up to almost a kbar level. Moreover, the formation of SynGAP/PSD-95 droplets is a very rapid process that can be switched on and off in seconds. In contrast with the marked effects of the cosolutes on droplet stability, at the cosolutes' respective biologically relevant concentrations, their impact on the phase transformation kinetics is rather small. Only a high TMAO concentration results in a significant kinetic retardation of LLPS. Taken together, these findings offer new biophysical insights into the neurological effects of hydrostatic pressure. In particular, our results indicate how pressure-induced neurological disorders might be alleviated by upregulating certain cosolutes in the cellular milieu.
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Affiliation(s)
- Hasan Cinar
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Rosario Oliva
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
| | - Haowei Wu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong, China.,School of Life Sciences, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hue Sun Chan
- Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Roland Winter
- Physical Chemistry I - Biophysical Chemistry, Department of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn-Strasse 4a, 44227 Dortmund, Germany
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20
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Folberth A, Bharadwaj S, van der Vegt NFA. Small-to-large length scale transition of TMAO interaction with hydrophobic solutes. Phys Chem Chem Phys 2022; 24:2080-2087. [PMID: 35018925 DOI: 10.1039/d1cp05167a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
We report the effect of trimethylamine N-oxide (TMAO) on the solvation of nonpolar solutes in water studied with molecular dynamics (MD) simulations and free-energy calculations. The simulation data indicate the occurrence of a length scale crossover in the TMAO interaction with repulsive Weeks-Chandler-Andersen (WCA) solutes: while TMAO is depleted from the hydration shell of a small WCA solute (methane) and increases the free-energy cost of solute-cavity formation, it preferentially binds to a large WCA solute (α-helical polyalanine), reducing the free-energy cost of solute-cavity formation via a surfactant-like mechanism. Significantly, we show that this surfactant-like behaviour of TMAO reinforces the solvent-mediated attraction between large WCA solutes by means of an entropic force linked to the interfacial accumulation of TMAO. Specifically, this entropic force arises from the natural tendency of adsorbed TMAO molecules to mix back into the bulk. It therefore favours solute-solute contact states that minimise the surface area exposed to the solvent and have a small overall number of TMAO molecules adsorbed. In contrast to the well-known depletion force, its effect is compensated by enthalpic solute-solvent interactions. Correspondingly, the hydrophobic association free energy of the large α-helical solutes passes through a minimum at low TMAO concentration when cohesive solute-solvent van der Waals interactions are considered. The observations reported herein are reminiscent to cosolvent effects on hydrophobic polymer coil-globule collapse free energies (Bharadwaj et al., Commun. Chem. 2020, 3, 165) and may be of general significance in systems whose properties are determined by hydrophobic self-assembly.
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Affiliation(s)
- Angelina Folberth
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany.
| | - Swaminath Bharadwaj
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany.
| | - Nico F A van der Vegt
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany.
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21
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Pica A, Graziano G. A Rationalization of the Effect That TMAO, Glycine, and Betaine Exert on the Collapse of Elastin-like Polypeptides. Life (Basel) 2022; 12:life12020140. [PMID: 35207427 PMCID: PMC8876568 DOI: 10.3390/life12020140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/13/2022] [Accepted: 01/16/2022] [Indexed: 11/16/2022] Open
Abstract
Elastin-like polypeptides (ELPs) are soluble in water at low temperature, but, on increasing the temperature, they undergo a reversible and cooperative, coil-to-globule collapse transition. It has been shown that the addition to water of either trimethylamine N-oxide (TMAO), glycine, or betaine causes a significant decrease of T(collapse) in the case of a specific ELP. Traditional rationalizations of these phenomena do not work in the present case. We show that an alternative approach, grounded in the magnitude of the solvent-excluded volume effect and its temperature dependence (strictly linked to the translational entropy of solvent and co-solute molecules), is able to rationalize the occurrence of ELP collapse in water on raising the temperature, as well as the T(collapse) lowering caused by the addition to water of either TMAO, glycine, or betaine.
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Affiliation(s)
- Andrea Pica
- ALPX, 71 Avenue des Martyrs, 38000 Grenoble, France;
| | - Giuseppe Graziano
- Dipartimento di Scienze e Tecnologie, Università del Sannio, Via Francesco de Sanctis snc, 82100 Benevento, Italy
- Correspondence:
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22
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Diaz-Marquez A, Stirnemann G. In silico all-atom approach to thermodiffusion in dilute aqueous solutions. J Chem Phys 2021; 155:174503. [PMID: 34742198 DOI: 10.1063/5.0067756] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Thermodiffusion (or thermophoresis) is the phenomenon by which the spatial distributions of constituents of liquid or gas phases become inhomogeneous in response to a temperature gradient. It has been evidenced in a variety of systems and has many practical applications as well as implications in the context of the origins of life. A complete molecular picture of thermophoresis is still missing, and phenomenological approaches are often employed to account for the experimental observations. In particular, the amplitude of the resulting concentration-gradients (quantified by the Soret coefficient) depends on many factors that are not straightforwardly rationalized. All-atom molecular dynamics simulations appear as an exquisite tool to shed light on the molecular origins for this phenomenon in molecular systems, but the practical implementation of thermophoretic settings in silico poses significant challenges. Here, we propose a robust approach to tackle thermophoresis in dilute realistic solutions at the molecular level. We rely on a recent enhanced heat-exchange algorithm to generate temperature-gradients. We carefully assess the convergence of thermophoretic simulations in dilute aqueous solutions. We show that simulations typically need to be propagated on long timescales (hundreds of nanoseconds). We find that the magnitude of the temperature gradient and the box sizes have little effect on the measured Soret coefficients. Practical guidelines are derived from such observations. Provided with this reliable setup, we discuss the results of thermophoretic simulations on several examples of molecular, neutral solutes, which we find in very good agreement with experimental measurements regarding the concentration-, mass-, and temperature-dependence of the Soret coefficient.
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Affiliation(s)
- Alejandro Diaz-Marquez
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, PSL University, Université de Paris, 13 rue Pierre et Marie Curie, 75005 Paris, France
| | - Guillaume Stirnemann
- CNRS Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, PSL University, Université de Paris, 13 rue Pierre et Marie Curie, 75005 Paris, France
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23
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Huang H, Zhang C, Crisci R, Lu T, Hung HC, Sajib MSJ, Sarker P, Ma J, Wei T, Jiang S, Chen Z. Strong Surface Hydration and Salt Resistant Mechanism of a New Nonfouling Zwitterionic Polymer Based on Protein Stabilizer TMAO. J Am Chem Soc 2021; 143:16786-16795. [PMID: 34582683 DOI: 10.1021/jacs.1c08280] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Zwitterionic polymers exhibit excellent nonfouling performance due to their strong surface hydrations. However, salt molecules may severely reduce the surface hydrations of typical zwitterionic polymers, making the application of these polymers in real biological and marine environments challenging. Recently, a new zwitterionic polymer brush based on the protein stabilizer trimethylamine N-oxide (TMAO) was developed as an outstanding nonfouling material. Using surface-sensitive sum frequency generation (SFG) vibrational spectroscopy, we investigated the surface hydration of TMAO polymer brushes (pTMAO) and the effects of salts and proteins on such surface hydration. It was discovered that exposure to highly concentrated salt solutions such as seawater only moderately reduced surface hydration. This superior resistance to salt effects compared to other zwitterionic polymers is due to the shorter distance between the positively and negatively charged groups, thus a smaller dipole in pTMAO and strong hydration around TMAO zwitterion. This results in strong bonding interactions between the O- in pTMAO and water, and weaker interaction between O- and metal cations due to the strong repulsion from the N+ and hydration water. Computer simulations at quantum and atomistic scales were performed to support SFG analyses. In addition to the salt effect, it was discovered that exposure to proteins in seawater exerted minimal influence on the pTMAO surface hydration, indicating complete exclusion of protein attachment. The excellent nonfouling performance of pTMAO originates from its extremely strong surface hydration that exhibits effective resistance to disruptions induced by salts and proteins.
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Affiliation(s)
| | | | | | | | - Hsiang-Chieh Hung
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Md Symon Jahan Sajib
- Department of Chemical Engineering, Howard University, Washington D.C. 20059, United States
| | - Pranab Sarker
- Department of Chemical Engineering, Howard University, Washington D.C. 20059, United States
| | - Jinrong Ma
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Tao Wei
- Department of Chemical Engineering, Howard University, Washington D.C. 20059, United States
| | - Shaoyi Jiang
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York 14853, United States
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24
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Roy S, Patra A, Palit DK, Mondal JA. Interaction of Zwitterionic Osmolyte Trimethylamine N-oxide (TMAO) with Molecular Hydrophobes: An Interplay of Hydrophobic and Electrostatic Interactions. J Phys Chem B 2021; 125:10939-10946. [PMID: 34570979 DOI: 10.1021/acs.jpcb.1c05694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Interaction of trimethylamine N-oxide (TMAO) with charged/uncharged moieties of proteins and lipids is an important elementary step toward the multifaceted biofunctions of TMAO. Using minimum area Raman difference spectroscopy (MA-RDS) of aqueous TMAO (1.0 M) in the presence of deuterated molecular hydrophobes (e.g., deuterated tetramethylammonium cation (d-TMA+) and tert-butylalcohol (d-TBA)), we show that TMAO exhibits two distinct motifs of interaction with the cationic (d-TMA+) and uncharged (d-TBA) hydrophobes. Specifically, the trimethylammonium moiety of TMAO undergoes van der Waals attraction with the tert-butyl group of d-TBA, which is governed by their mutual hydrophobic interaction with water. This makes their methyl groups less exposed to water. In contrast, for the cationic hydrophobe (d-TMA+), TMAO interacts electrostatically via its negatively charged-oxygen, which in turn orients the TMAO-methyls away from the hydrophobe (d-TMA+), keeping them exposed to water.
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Affiliation(s)
- Subhadip Roy
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Homi Bhabha National Institute, Trombay, Mumbai 400085, India
| | - Animesh Patra
- School of Chemistry, Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Santacruz (E), Mumbai 400098, India
| | - Dipak K Palit
- School of Chemistry, Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Santacruz (E), Mumbai 400098, India
| | - Jahur Alam Mondal
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Homi Bhabha National Institute, Trombay, Mumbai 400085, India
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25
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Hydration and aggregation in aqueous xylitol solutions in the wide temperature range. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.116838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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26
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Nie J, Tian F, Zheng B, Wang Z, Zheng P. Exploration of Metal-Ligand Coordination Bonds in Proteins by Single-molecule Force Spectroscopy. CHEM LETT 2021. [DOI: 10.1246/cl.210307] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Jingyuan Nie
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Fang Tian
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Bin Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Ziyi Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
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27
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Smirnov MA, Tolmachev DA, Glova AD, Sokolova MP, Geydt PV, Lukasheva NV, Lyulin SV. Combined Use of Atomic Force Microscopy and Molecular Dynamics in the Study of Biopolymer Systems. POLYMER SCIENCE SERIES C 2021. [DOI: 10.1134/s1811238221020089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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28
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Ahlawat V, Rajput SS, Patil S. Elasticity of single flexible polymer chains in good and poor solvents. POLYMER 2021. [DOI: 10.1016/j.polymer.2021.124031] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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29
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Sarkar S, Mondal J. Mechanistic Insights on ATP's Role as a Hydrotrope. J Phys Chem B 2021; 125:7717-7731. [PMID: 34240882 DOI: 10.1021/acs.jpcb.1c03964] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Hydrotropes are the small amphiphilic molecules which help in solubilizing hydrophobic entities in an aqueous medium. Recent experimental investigation has provided convincing evidence that adenosine triphosphate (ATP), besides being the energy currency of cell, also can act as a hydrotrope to inhibit the formation of protein condensates. In this work, we have designed computer simulations of prototypical macromolecules in aqueous ATP solution to dissect the molecular mechanism underlying ATP's newly discovered role as a hydrotrope. The simulation demonstrates that ATP can unfold a single chain of hydrophobic macromolecule as well as can disrupt the aggregation process of a hydrophobic assembly. Moreover, the introduction of charges in the macromolecule is found to reinforce ATP's disaggregation effects in a synergistic fashion, a behavior reminiscent of recent experimental observation of pronounced hydrotropic action of ATP in intrinsically disordered proteins. Molecular analysis indicates that this newfound ability of ATP is ingrained in its propensity of preferential binding to the polymer surface, which gets fortified in the presence of charges. The investigation also renders evidence that the key to the ATP's superior hydrotropic role over chemical hydrotropes (sodium xylene sulfonate, NaXS) may lie in its inherent self-aggregation propensity. Overall, via employing a bottom-up approach, the current investigation provides fresh mechanistic insights into the dual solubilizing and denaturing abilities of ATP.
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Affiliation(s)
- Susmita Sarkar
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
| | - Jagannath Mondal
- Center for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
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30
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Joshi PU, Turpeinen DG, Schroeder M, Jones B, Lyons A, Kriz S, Khaksari M, O'Hagan D, Nikam S, Heldt CL. Osmolyte enhanced aqueous two-phase system for virus purification. Biotechnol Bioeng 2021; 118:3251-3262. [PMID: 34129733 DOI: 10.1002/bit.27849] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 05/26/2021] [Accepted: 06/02/2021] [Indexed: 01/15/2023]
Abstract
Due to the high variation in viral surface properties, a platform method for virus purification is still lacking. A potential alternative to the high-cost conventional methods is aqueous two-phase systems (ATPSs). However, optimizing virus purification in ATPS requires a large experimental design space, and the optimized systems are generally found to operate at high ATPS component concentrations. The high concentrations capitalize on hydrophobic and electrostatic interactions to obtain high viral particle yields. This study investigated using osmolytes as driving force enhancers to reduce the high concentration of ATPS components while maintaining high yields. The partitioning behavior of porcine parvovirus (PPV), a nonenveloped mammalian virus, and human immunodeficiency virus-like particle (HIV-VLP), a yeast-expressed enveloped VLP, were studied in a polyethylene glycol (PEG) 12 kDa-citrate system. The partitioning of the virus modalities was enhanced by osmoprotectants glycine and betaine, while trimethylamine N-oxide was ineffective for PPV. The increased partitioning to the PEG-rich phase pertained only to viruses, resulting in high virus purification. Recoveries were 100% for infectious PPV and 92% for the HIV-VLP, with high removal of the contaminant proteins and more than 60% DNA removal when glycine was added. The osmolyte-induced ATPS demonstrated a versatile method for virus purification, irrespective of the expression system.
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Affiliation(s)
- Pratik U Joshi
- Department of Chemical Engineering, Michigan Technological University, Houghton, Michigan, USA.,Health Research Institute, Michigan Technological University, Houghton, Michigan, USA
| | - Dylan G Turpeinen
- Department of Chemical Engineering, Michigan Technological University, Houghton, Michigan, USA.,Health Research Institute, Michigan Technological University, Houghton, Michigan, USA
| | - Michael Schroeder
- Department of Chemical Engineering, Michigan Technological University, Houghton, Michigan, USA
| | - Bianca Jones
- Department of Biochemistry, University of Detroit-Mercy, Detroit, Michigan, USA
| | - Audrey Lyons
- Department of Chemical Engineering, Michigan Technological University, Houghton, Michigan, USA
| | - Seth Kriz
- Department of Chemical Engineering, Michigan Technological University, Houghton, Michigan, USA.,Health Research Institute, Michigan Technological University, Houghton, Michigan, USA
| | - Maryam Khaksari
- Great Lakes Research Center, Michigan Technological University, Houghton, Michigan, USA
| | | | | | - Caryn L Heldt
- Department of Chemical Engineering, Michigan Technological University, Houghton, Michigan, USA.,Health Research Institute, Michigan Technological University, Houghton, Michigan, USA
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31
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Dhabal D, Jiang Z, Pallath A, Patel AJ. Characterizing the Interplay between Polymer Solvation and Conformation. J Phys Chem B 2021; 125:5434-5442. [PMID: 33978411 DOI: 10.1021/acs.jpcb.1c02191] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Conformational transitions of flexible molecules, especially those driven by hydrophobic effects, tend to be hindered by desolvation barriers. For such transitions, it is thus important to characterize and understand the interplay between solvation and conformation. Using specialized molecular simulations, here we perform such a characterization for a hydrophobic polymer solvated in water. We find that an external potential, which unfavorably perturbs the polymer hydration waters, can trigger a coil-to-globule or collapse transition, and that the relative stabilities of the collapsed and extended states can be quantified by the strength of the requisite potential. Our results also provide mechanistic insights into the collapse transition, highlighting that the bottleneck to polymer collapse is the formation of a sufficiently large cluster, and the collective dewetting of such a cluster. We also study the collapse of the hydrophobic polymer in octane, a nonpolar solvent, and interestingly, we find that the mechanistic details of the transition are qualitatively similar to that in water.
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Affiliation(s)
- Debdas Dhabal
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Zhitong Jiang
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Akash Pallath
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Amish J Patel
- Department of Chemical and Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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32
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Bharadwaj S, Nayar D, Dalgicdir C, van der Vegt NFA. An interplay of excluded-volume and polymer-(co)solvent attractive interactions regulates polymer collapse in mixed solvents. J Chem Phys 2021; 154:134903. [PMID: 33832270 DOI: 10.1063/5.0046746] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cosolvent effects on the coil-globule transitions in aqueous polymer solutions are not well understood, especially in the case of amphiphilic cosolvents that preferentially adsorb on the polymer and lead to both polymer swelling and collapse. Although a predominant focus in the literature has been placed on the role of polymer-cosolvent attractive interactions, our recent work has shown that excluded-volume interactions (repulsive interactions) can drive both preferential adsorption of the cosolvent and polymer collapse via a surfactant-like mechanism. Here, we further study the role of polymer-(co)solvent attractive interactions in two kinds of polymer solutions, namely, good solvent (water)-good cosolvent (alcohol) (GSGC) and poor solvent-good cosolvent (PSGC) solutions, both of which exhibit preferential adsorption of the cosolvent and a non-monotonic change in the polymer radius of gyration with the addition of the cosolvent. Interestingly, at low concentrations, the polymer-(co)solvent energetic interactions oppose polymer collapse in the GSGC solutions and contrarily support polymer collapse in the PSGC solutions, indicating the importance of the underlying polymer chemistry. Even though the alcohol molecules are preferentially adsorbed on the polymer, the trends of the energetic interactions at low cosolvent concentrations are dominated by the polymer-water energetic interactions in both the cases. Therefore, polymer-(co)solvent energetic interactions can either reinforce or compensate the surfactant-like mechanism, and it is this interplay that drives coil-to-globule transitions in polymer solutions. These results have implications for rationalizing the cononsolvency transitions in real systems such as polyacrylamides in aqueous alcohol solutions where the understanding of microscopic driving forces is still debatable.
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Affiliation(s)
- Swaminath Bharadwaj
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Divya Nayar
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Cahit Dalgicdir
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Nico F A van der Vegt
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
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33
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Judy E, Kishore N. Quantitative calorimetric evidences into counteraction mechanism of denaturing effect of guanidine hydrochloride by citrulline and betaine. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2020.114953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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34
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Mendes de Oliveira D, Ben-Amotz D. Spectroscopically Quantifying the Influence of Salts on Nonionic Surfactant Chemical Potentials and Micelle Formation. J Phys Chem Lett 2021; 12:355-360. [PMID: 33355467 DOI: 10.1021/acs.jpclett.0c03349] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The influence of two salts (NaSCN and Na2SO4) on the micellization of a nonionic surfactant (1,2-hexanediol) is quantified using Raman multivariate curve resolution spectroscopy, combined with a generalized theoretical analysis of the corresponding chemical potential changes. Although the SCN- and SO42- anions are on opposite ends of the Hofmeister series, they are both found to lower the critical micelle concentration. Our combined spectroscopic and theoretical analysis traces these observations to the fact that in both salt solutions the ions have a greater affinity for (or are less strongly expelled from) the hydration shell of the micelle than the free surfactant monomer, as quantified using the corresponding chemical potentials and Wyman-Tanford coefficients. This probe-free experimental and theoretical analysis strategy may readily be extended to micelle formation processes involving other surfactants, salts, and cosolvents, as well as to other sorts of aggregation and binding processes.
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Affiliation(s)
| | - Dor Ben-Amotz
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
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35
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Mukherjee M, Mondal J. Bottom-Up View of the Mechanism of Action of Protein-Stabilizing Osmolytes. J Phys Chem B 2020; 124:11316-11323. [PMID: 33198465 DOI: 10.1021/acs.jpcb.0c06658] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The molecular mechanism of osmolytes on the stabilization of native states of protein is still controversial irrespective of extensive studies over several decades. Recent investigations in terms of experiments and molecular dynamics simulations challenge the popular osmophobic model explaining the mechanistic action of protein-stabilizing osmolytes. The current Perspective presents an updated view on the mechanistic action of osmolytes in light of resurgence of interesting experiments and computer simulations over the past few years in this direction. In this regard, the Perspective adopts a bottom-up approach starting from hydrophobic interactions and eventually adds complexity in the system, going toward the protein, in a complex topology of hydrophobic and electrostatic interactions. Finally, the Perspective unifies osmolyte-induced protein conformational equilibria in terms of preferential interaction theory, irrespective of individual preferential binding or exclusion of osmolytes depending on different osmolytes and protein surfaces. The Perspective also identifies future research directions that can potentially shape this interesting area.
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Affiliation(s)
- Mrinmoy Mukherjee
- Tata Institute of Fundamental Research, Center For Interdisciplinary Sciences, Hyderabad 500107, India
| | - Jagannath Mondal
- Tata Institute of Fundamental Research, Center For Interdisciplinary Sciences, Hyderabad 500107, India
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36
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Nandakumar A, Ito Y, Ueda M. Solvent Effects on the Self-Assembly of an Amphiphilic Polypeptide Incorporating α-Helical Hydrophobic Blocks. J Am Chem Soc 2020; 142:20994-21003. [PMID: 33272014 DOI: 10.1021/jacs.0c03425] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The self-assembly of biological molecules is an important pathway to understanding the molecular basis of complex metabolic events. The presence of a cosolvent in an aqueous solution during the self-assembly process can promote the formation of kinetically trapped metastable intermediates. In nature, a category of cosolvents termed osmolytes can work to strengthen the hydrogen-bond network of water such that the native states of certain proteins are favored, thus modulating their function and stability. However, identifying cosolvents that act as osmolytes in biomimetic applications, such as the self-assembly of soft materials, remains challenging. The present work examined the effects of ethanol (EtOH) and acetonitrile (ACN) as cosolvents on the self-assembly of the amphiphilic polypeptide PSar30-(l-Leu-Aib)6 (S30L12), which incorporates α-helical hydrophobic blocks, in aqueous solution. The results provided a direct observation of morphological behavior of S30L12 as a function of solvent composition. Morphological transitions were investigated using transmission electron microscopy, while the packing of peptide molecules was assessed using circular dichroism analyses and evaluations of membrane fluidity. In the EtOH/H2O mixtures, the EtOH strengthened the hydrogen-bond network of the water, thus limiting the hydrophobic hydration of S30L12 assemblies and enhancing hydrophobic interactions between assemblies. In contrast, ACN formed self-associated nanoclusters in water and at the hydrophobic cores of peptide assemblies to stabilize the edges exposed to bulk water and enhance the assembly kinetics. Fourier transform infrared (FT-IR) analysis indicated that both EtOH and ACN can modify the self-assembly of biomaterials in the same manner as osmolyte protectants or denaturants.
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Affiliation(s)
- Avanashiappan Nandakumar
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yoshihiro Ito
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Motoki Ueda
- Emergent Bioengineering Materials Research Team, RIKEN Center for Emergent Matter Science (CEMS), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.,Nano Medical Engineering Laboratory, RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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37
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A cosolvent surfactant mechanism affects polymer collapse in miscible good solvents. Commun Chem 2020; 3:165. [PMID: 36703319 PMCID: PMC9814688 DOI: 10.1038/s42004-020-00405-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 10/14/2020] [Indexed: 01/29/2023] Open
Abstract
The coil-globule transition of aqueous polymers is of profound significance in understanding the structure and function of responsive soft matter. In particular, the remarkable effect of amphiphilic cosolvents (e.g., alcohols) that leads to both swelling and collapse of stimuli-responsive polymers has been hotly debated in the literature, often with contradictory mechanisms proposed. Using molecular dynamics simulations, we herein demonstrate that alcohols reduce the free energy cost of creating a repulsive polymer-solvent interface via a surfactant-like mechanism which surprisingly drives polymer collapse at low alcohol concentrations. This hitherto neglected role of interfacial solvation thermodynamics is common to all coil-globule transitions, and rationalizes the experimentally observed effects of higher alcohols and polymer molecular weight on the coil-to-globule transition of thermoresponsive polymers. Polymer-(co)solvent attractive interactions reinforce or compensate this mechanism and it is this interplay which drives polymer swelling or collapse.
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38
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Mochizuki K. On-Off of Co-non-solvency for Poly( N-vinylcaprolactam) in Alcohol-Water Mixtures: A Molecular Dynamics Study. J Phys Chem B 2020; 124:9951-9957. [PMID: 33086006 DOI: 10.1021/acs.jpcb.0c07188] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Poly(N-vinylcaprolactam) (PVCL) exhibits co-non-solvency in aqueous solutions of 2-propanol but not in methanol. What distinguishes the impact of these two cosolvents on the polymer conformational stability? We report a molecular dynamics simulation study on PVCL 50-mer and monomers dissolved in methanol-water and 2-propanol-water mixtures. We show that the alcohol-concentration dependence of the effective attraction between a pair of PVCL monomers closely resembles the conformational changes in a single PVCL 50-mer as well as the experimentally observed behavior for PVCL chains. We also found that, at the co-non-solvency maximum, the monomer-monomer attraction works over a long-range beyond the solvent-separated distance. Then, we correlate the long-range attraction to the appearance of a dense alcohol concentration accumulated between the monomers. Furthermore, we distinctly demonstrate that the co-non-solvency of PVCL monomers can be switched on/off by artificially tuning the alcohol size while keeping the energetic parameters. Thus, we conclude that the magnitude of the excluded volume effect in alcohol accompanying the gain in translational entropy of the solvent is crucial to the occurrence of PVCL polymer co-non-solvency.
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Affiliation(s)
- Kenji Mochizuki
- Department of Chemistry, Zhejiang University, 148 Tianmushan Road, Hangzhou, Zhejiang 310028, P. R. China
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39
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Song G, Ding X, Liu H, Yuan G, Tian F, Shi S, Yang Y, Li G, Zheng P. Single-Molecule Force Spectroscopy Reveals that the Fe-N Bond Enables Multiple Rupture Pathways of the 2Fe2S Cluster in a MitoNEET Monomer. Anal Chem 2020; 92:14783-14789. [PMID: 33048522 DOI: 10.1021/acs.analchem.0c03536] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The mitochondrial outer membrane protein, mitoNEET (mNT), is an iron-sulfur protein containing an Fe2S2(His)1(Cys)3 cluster with a unique single Fe-N bond. Previous studies have shown that this Fe(III)-N(His) bond is essential for metal cluster transfer and protein function. To further understand the effect of this unique Fe-N bond on the metal cluster and protein, we used atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS) to investigate the mechanical unfolding mechanism of an mNT monomer, focusing on the rupture pathway and kinetic stability of the cluster. We found that the Fe-N bond was the weakest point of the cluster, the rupture of which occurred first, and could be independent of the cluster break. Moreover, this Fe-N bond enabled a dynamic and labile iron-sulfur cluster, as multiple unfolding pathways of mNT with a unique Fe2S2(Cys)3 intermediate were observed accordingly.
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Affiliation(s)
- Guobin Song
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Xuan Ding
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Huaxing Liu
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Guodong Yuan
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Fang Tian
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Shengchao Shi
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Yang Yang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Guoqiang Li
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Peng Zheng
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
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40
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Li J, Chen J, An L, Yuan X, Yao L. Polyol and sugar osmolytes can shorten protein hydrogen bonds to modulate function. Commun Biol 2020; 3:528. [PMID: 32968183 PMCID: PMC7511342 DOI: 10.1038/s42003-020-01260-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 08/28/2020] [Indexed: 12/19/2022] Open
Abstract
Polyol and sugar osmolytes are commonly used in therapeutic protein formulations. How they may affect protein structure and function is an important question. In this work, through NMR measurements, we show that glycerol and sorbitol (polyols), as well as glucose (sugar), can shorten protein backbone hydrogen bonds. The hydrogen bond shortening is also captured by molecular dynamics simulations, which suggest a hydrogen bond competition mechanism. Specifically, osmolytes weaken hydrogen bonds between the protein and solvent to strengthen those within the protein. Although the hydrogen bond change is small, with the average experimental cross hydrogen bond 3hJNC' coupling of two proteins GB3 and TTHA increased by ~ 0.01 Hz by the three osmolytes (160 g/L), its effect on protein function should not be overlooked. This is exemplified by the PDZ3-peptide binding where several intermolecular hydrogen bonds are formed and osmolytes shift the equilibrium towards the bound state.
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Affiliation(s)
- Jingwen Li
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Jingfei Chen
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Liaoyuan An
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoxiang Yuan
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lishan Yao
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
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41
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Folberth A, Polák J, Heyda J, van der Vegt NFA. Pressure, Peptides, and a Piezolyte: Structural Analysis of the Effects of Pressure and Trimethylamine- N-oxide on the Peptide Solvation Shell. J Phys Chem B 2020; 124:6508-6519. [PMID: 32615760 DOI: 10.1021/acs.jpcb.0c03319] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The osmolyte trimethylamine-N-oxide (TMAO) is able to increase the thermodynamic stability of folded proteins, counteracting pressure denaturation. Herein, we report experimental solubility data on penta-alanine (pAla) in aqueous TMAO solutions (at pH = 7 and pH = 13) together with molecular simulation data for pAla, penta-serine (pSer), and an elastin-like peptide (ELP) sequence (VPGVG) under varying pH and pressure conditions. The effect of the peptide end groups on TMAO-peptide interactions is investigated by comparing the solvation of zwitterionic and negatively charged pentamers with the solvation of pentamers with charge-neutral C- and N-termini and linear, virtually infinite, peptide chains stretched across the periodic boundaries of the simulation cell. The experiments and simulations consistently show that TMAO is net-depleted from the pAla-water interface, but local accumulation of TMAO is observed just outside the first hydration shell of the peptide. While the same observations are also made in the simulations of the zwitterionic pentamers (Ala, Ser, and ELP) and virtually infinite peptide chains (Ala and ELP), weak preferential binding of TMAO is instead observed for pAla with neutral end groups at a 1 M TMAO concentration and for an ELP pentamer with capped neutral end groups at a 0.55 M TMAO concentration studied in previous work (Y.-T. Liao et al. Proc. Natl. Acad. Sci. USA, 2017, 114, 2479-2484). The above observations made at 1 bar ambient pressure remain qualitatively unchanged at 500 bar and 2 kbar. Local accumulation of TMAO correlates with a reduction in the total number of peptide-solvent hydrogen bonds, independent of the peptide's primary sequence and the applied pressure. By weakening water hydrogen bonds with the protein backbone, TMAO indirectly contributes to stabilizing internal hydrogen bonds in proteins, thus providing a protein stabilization mechanism beyond net depletion.
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Affiliation(s)
- Angelina Folberth
- Eduard-Zintl-Institut fuer Anorganische und Physikalische Chemie, Technical University of Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
| | - Jakub Polák
- Physical Chemistry Department, University of Chemistry and Technology, Prague Technicka 5, 16628 Prague 6, Czech Republic
| | - Jan Heyda
- Physical Chemistry Department, University of Chemistry and Technology, Prague Technicka 5, 16628 Prague 6, Czech Republic
| | - Nico F A van der Vegt
- Eduard-Zintl-Institut fuer Anorganische und Physikalische Chemie, Technical University of Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
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42
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Alomari MI. Conformational Relative Stability and Thermal Properties of Succinonitrile in Gas and Condensed Phases: Using CCSD and DFT Calculations. ChemistrySelect 2020. [DOI: 10.1002/slct.202001804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Mohammed I. Alomari
- Faculty of Art and Sciences Department of Chemistry, University of Petra Amman 961343 Jordan
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43
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Mukherjee M, Mondal J. Unifying the Contrasting Mechanisms of Protein-Stabilizing Osmolytes. J Phys Chem B 2020; 124:6565-6574. [DOI: 10.1021/acs.jpcb.0c04757] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Mrinmoy Mukherjee
- Tata Institute of Fundamental Research, Center for Interdisciplinary Sciences, Hyderabad 500046, India
| | - Jagannath Mondal
- Tata Institute of Fundamental Research, Center for Interdisciplinary Sciences, Hyderabad 500046, India
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44
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Frenzel L, Lokteva I, Koof M, Narayanan S, Grübel G, Lehmkühler F. Influence of TMAO as co-solvent on the gelation of silica-PNIPAm core-shell nanogels at intermediate volume fractions. Chemphyschem 2020; 21:1318-1325. [PMID: 32250508 PMCID: PMC7318175 DOI: 10.1002/cphc.202000114] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 03/20/2020] [Indexed: 12/29/2022]
Abstract
We study the structure and dynamics of poly(N-isopropylacrylamide) (PNIPAm) core-shell nanogels dispersed in aqueous trimethylamine N-oxide (TMAO) solutions by means of small-angle X-ray scattering and X-ray photon correlation spectroscopy (XPCS). Upon increasing the temperature above the lower critical solution temperature of PNIPAm at 33 °C, a colloidal gel is formed as identified by an increase of I(q) at small q as well as a slowing down of sample dynamics by various orders of magnitude. With increasing TMAO concentration the gelation transition shifts linearly to lower temperatures. Above a TMAO concentration of approximately 0.40 mol/L corresponding to a 1 : 1 ratio of TMAO and NIPAm groups, collapsed PNIPAm states are found for all temperatures without any gelation transition. This suggests that reduction of PNIPAm-water hydrogen bonds due to the presence of TMAO results in a stabilisation of the collapsed PNIPAm state and suppresses gelation of the nanogel.
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Affiliation(s)
- Lara Frenzel
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Irina Lokteva
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Michael Koof
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Suresh Narayanan
- Advanced Photon SourceArgonne National LaboratoryArgonneIllinois60439United States
| | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
| | - Felix Lehmkühler
- Deutsches Elektronen-Synchrotron DESYNotkestr. 8522607HamburgGermany
- The Hamburg Centre for Ultrafast ImagingLuruper Chaussee 14922761HamburgGermany
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45
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Ganguly P, Polák J, van der Vegt NFA, Heyda J, Shea JE. Protein Stability in TMAO and Mixed Urea–TMAO Solutions. J Phys Chem B 2020; 124:6181-6197. [DOI: 10.1021/acs.jpcb.0c04357] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Pritam Ganguly
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106, United States
| | - Jakub Polák
- Department of Physical Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Nico F. A. van der Vegt
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 10, Darmstadt 64287, Germany
| | - Jan Heyda
- Department of Physical Chemistry, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague 6, Czech Republic
| | - Joan-Emma Shea
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California 93106, United States
- Department of Physics, University of California at Santa Barbara, Santa Barbara, California 93106, United States
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46
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Chéron N, Naepels M, Pluhařová E, Laage D. Protein Preferential Solvation in Water:Glycerol Mixtures. J Phys Chem B 2020; 124:1424-1437. [PMID: 31999925 DOI: 10.1021/acs.jpcb.9b11190] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
For proteins in solvent mixtures, the relative abundances of each solvent in their solvation shell have a critical impact on their properties. Preferential solvation of a series of proteins in water-glycerol mixtures is studied here over a broad range of solvent compositions via classical molecular dynamics simulations. Our simulation results reveal that the differences between shell and bulk compositions exhibit dramatic changes with solvent composition, temperature, and protein nature. In contrast with the simple and widely used picture where glycerol is completely excluded from the protein interface, we show that for aqueous solutions with less than 50% glycerol in volume, protein solvation shells have approximately the same composition as the bulk solvent and proteins are in direct contact with glycerol. We further demonstrate that at high glycerol concentration, glycerol depletion from the solvation shell is due to an entropic factor arising from the reduced accessibility of bulky glycerol molecules in protein cavities. The resulting molecular picture is important to understand protein activity and cryopreservation in mixed aqueous solvents.
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Affiliation(s)
- Nicolas Chéron
- PASTEUR, Département de chimie , École Normale Supérieure, PSL University, Sorbonne Université, CNRS , 75005 Paris , France
| | - Margaux Naepels
- PASTEUR, Département de chimie , École Normale Supérieure, PSL University, Sorbonne Université, CNRS , 75005 Paris , France
| | - Eva Pluhařová
- PASTEUR, Département de chimie , École Normale Supérieure, PSL University, Sorbonne Université, CNRS , 75005 Paris , France
| | - Damien Laage
- PASTEUR, Département de chimie , École Normale Supérieure, PSL University, Sorbonne Université, CNRS , 75005 Paris , France
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47
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Cosolvent effects on the growth of amyloid fibrils. Curr Opin Struct Biol 2020; 60:101-109. [DOI: 10.1016/j.sbi.2019.12.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 12/08/2019] [Accepted: 12/16/2019] [Indexed: 02/05/2023]
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48
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Sahle CJ, Schroer MA, Niskanen J, Elbers M, Jeffries CM, Sternemann C. Hydration in aqueous osmolyte solutions: the case of TMAO and urea. Phys Chem Chem Phys 2020; 22:11614-11624. [DOI: 10.1039/c9cp06785j] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
X-ray Raman scattering spectroscopy and first principles simulations reveal details of the hydration and hydrogen-bond topology of trimethylamine N-oxide (TMAO) and urea in aqueous solutions.
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Affiliation(s)
| | - Martin A. Schroer
- European Molecular Biology Laboratory (EMBL)
- Hamburg Outstation c/o DESY
- Hamburg 22607
- Germany
| | - Johannes Niskanen
- Department of Physics and Astronomy
- University of Turku
- FI-20014 Turun Yliopisto
- Finland
| | - Mirko Elbers
- Fakultät Physik/DELTA
- Technische Universität Dortmund
- 44221 Dortmund
- Germany
| | - Cy M. Jeffries
- European Molecular Biology Laboratory (EMBL)
- Hamburg Outstation c/o DESY
- Hamburg 22607
- Germany
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49
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Laurent H, Soper AK, Dougan L. Trimethylamine N-oxide (TMAO) resists the compression of water structure by magnesium perchlorate: terrestrial kosmotrope vs. Martian chaotrope. Phys Chem Chem Phys 2020; 22:4924-4937. [PMID: 32091074 DOI: 10.1039/c9cp06324b] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Neutron diffraction and computational modelling provide insight into water structure.
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Affiliation(s)
| | - Alan K. Soper
- ISIS Facility
- STFC Rutherford Appleton Laboratory
- Didcot
- UK
| | - Lorna Dougan
- Department of Physics and Astronomy
- University of Leeds
- Leeds
- UK
- Astbury Centre for Structural and Molecular Biology
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50
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Nanomechanical properties of steric zipper globular structures. Proc Natl Acad Sci U S A 2019; 116:22478-22484. [PMID: 31636220 DOI: 10.1073/pnas.1908782116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The term amyloid defines a group of proteins that aggregate into plaques or fibers. Amyloid fibers gained their fame mostly due to their relation with neurodegenerative diseases in humans. However, secreted by lower organisms, such as bacteria and fungi, amyloid fibers play a functional role: for example, when they serve as cement in the extracellular matrix of biofilms. Originating either in humans or in microorganisms, the sequence of amyloid proteins is decorated with hexapeptides with high propensity to form fibers, known as steric zippers. We have found that steric zippers form globular structures on route to making fibers and exhibit a characteristic force-distance (F-D) fingerprint when pulled with an atomic force microscope (AFM) tip. Particularly, the F-D pulling curves showed force plateau steps, suggesting that the globular structures were composed of chains that were unwound like a yarn ball. Force plateau analysis showed that the F-D characteristic parameters were sequence sensitive, representing differences in the packing of the hexapeptides within the globules. These unprecedented findings show that steric zippers exhibit a characteristic nanomechanical signature in solution in addition to previously observed characteristic crystallographic structure. Getting to the fundamental interactions that govern the unzipping of full-length amyloid fibers may initiate the development of antiamyloid methods that target the physical in addition to the structural properties of steric zippers.
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