1
|
Mengel SD, DeStefano AJ, Webber T, Semerdjiev A, Han S, Segalman RA. Salt-Screened Transition toward Bulk-Like Water Dynamics near Polymeric Zwitterions. ACS Macro Lett 2024; 13:928-934. [PMID: 38995998 DOI: 10.1021/acsmacrolett.4c00347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/14/2024]
Abstract
The superior antifouling performance of zwitterionic materials is commonly linked to their hydration structure, in which tight surface binding of water molecules inhibits solute adsorption. However, there is comparatively little direct experimental data on the hydration water structure and dynamics around zwitterionic moieties, including the longer-range behavior of the hydration shell that modulates the approach of solutes to the polymer surface. This work experimentally probes the dynamics of the diffusing hydration water molecules around a series of zwitterion chemistries using Overhauser dynamic nuclear polarization relaxometry. Surprisingly, water dynamics measured within ∼1 nm of the zwitterions were minimally inhibited compared to those near uncharged hydrophilic or cationic side chains. Specific dissolved ions further enhance the water diffusivity near the zwitterions, rendering the hydration shell bulk water-like. These results that the hydration of a zwitterion surface is nearly indistinguishable from bulk water suggest that these surfaces are "invisible" to biological constituents in a manner tunable by the ionic environment and the chemical design of the zwitterionic surface.
Collapse
Affiliation(s)
- Shawn D Mengel
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Audra J DeStefano
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Thomas Webber
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Anton Semerdjiev
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Songi Han
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Rachel A Segalman
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
- Department of Materials, University of California, Santa Barbara, California 93106, United States
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
2
|
Robinson Brown DC, Webber TR, Casey TM, Franck J, Shell MS, Han S. Computation of Overhauser dynamic nuclear polarization processes reveals fundamental correlation between water dynamics, structure, and solvent restructuring entropy. Phys Chem Chem Phys 2024; 26:14637-14650. [PMID: 38742831 DOI: 10.1039/d4cp00030g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
Hydration water dynamics, structure, and thermodynamics are crucially important to understand and predict water-mediated properties at molecular interfaces. Yet experimentally and directly quantifying water behavior locally near interfaces at the sub-nanometer scale is challenging, especially at interfaces submerged in biological solutions. Overhauser dynamic nuclear polarization (ODNP) experiments measure equilibrium hydration water dynamics within 8-15 angstroms of a nitroxide spin probe on instantaneous timescales (10 picoseconds to nanoseconds), making ODNP a powerful tool for probing local water dynamics in the vicinity of the spin probe. As with other spectroscopic techniques, concurrent computational analysis is necessary to gain access to detailed molecular level information about the dynamic, structural, and thermodynamic properties of water from experimental ODNP data. We chose a model system that can systematically tune the dynamics of water, a water-glycerol mixture with compositions ranging from 0 to 0.3 mole fraction glycerol. We demonstrate the ability of molecular dynamics (MD) simulations to compute ODNP spectroscopic quantities, and show that translational, rotational, and hydrogen bonding dynamics of hydration water align strongly with spectroscopic ODNP parameters. Moreover, MD simulations show tight correlations between the dynamic properties of water that ODNP captures and the structural and thermodynamic behavior of water. Hence, experimental ODNP readouts of varying water dynamics suggest changes in local structural and thermodynamic hydration water properties.
Collapse
Affiliation(s)
- Dennis C Robinson Brown
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA
| | - Thomas R Webber
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA
| | - Thomas M Casey
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA
| | - John Franck
- Department of Chemistry, Syracuse University, Syracuse, NY, USA
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
| |
Collapse
|
3
|
Jaufer AM, Bouhadana A, Fanucci GE. Hydrophobic Clusters Regulate Surface Hydration Dynamics of Bacillus subtilis Lipase A. J Phys Chem B 2024; 128:3919-3928. [PMID: 38628066 DOI: 10.1021/acs.jpcb.4c00405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The surface hydration diffusivity of Bacillus subtilis Lipase A (BSLA) has been characterized by low-field Overhauser dynamic nuclear polarization (ODNP) relaxometry using a series of spin-labeled constructs. Sites for spin-label incorporation were previously designed via an atomistic computational approach that screened for surface exposure, reflective of the surface hydration comparable to other proteins studied by this method, as well as minimal impact on protein function, dynamics, and structure of BSLA by excluding any surface site that participated in greater than 30% occupancy of a hydrogen bonding network within BSLA. Experimental ODNP relaxometry coupling factor results verify the overall surface hydration behavior for these BSLA spin-labeled sites similar to other globular proteins. Here, by plotting the ODNP parameters of relative diffusive water versus the relative bound water, we introduce an effective "phase-space" analysis, which provides a facile visual comparison of the ODNP parameters of various biomolecular systems studied to date. We find notable differences when comparing BSLA to other systems, as well as when comparing different clusters on the surface of BSLA. Specifically, we find a grouping of sites that correspond to the spin-label surface location within the two main hydrophobic core clusters of the branched aliphatic amino acids isoleucine, leucine, and valine cores observed in the BSLA crystal structure. The results imply that hydrophobic clustering may dictate local surface hydration properties, perhaps through modulation of protein conformations and samplings of the unfolded states, providing insights into how the dynamics of the hydration shell is coupled to protein motion and fluctuations.
Collapse
Affiliation(s)
- Afnan M Jaufer
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
- George and Josephine Butler Polymer Research Laboratory, University of Florida, Gainesville, Florida 32611, United States
| | - Adam Bouhadana
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Gail E Fanucci
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
- George and Josephine Butler Polymer Research Laboratory, University of Florida, Gainesville, Florida 32611, United States
| |
Collapse
|
4
|
Moon JD, Webber TR, Brown DR, Richardson PM, Casey TM, Segalman RA, Shell MS, Han S. Nanoscale water-polymer interactions tune macroscopic diffusivity of water in aqueous poly(ethylene oxide) solutions. Chem Sci 2024; 15:2495-2508. [PMID: 38362435 PMCID: PMC10866362 DOI: 10.1039/d3sc05377f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Accepted: 11/30/2023] [Indexed: 02/17/2024] Open
Abstract
The separation and anti-fouling performance of water purification membranes is governed by both macroscopic and molecular-scale water properties near polymer surfaces. However, even for poly(ethylene oxide) (PEO) - ubiquitously used in membrane materials - there is little understanding of whether or how the molecular structure of water near PEO surfaces affects macroscopic water diffusion. Here, we probe both time-averaged bulk and local water dynamics in dilute and concentrated PEO solutions using a unique combination of experimental and simulation tools. Pulsed-Field Gradient NMR and Overhauser Dynamic Nuclear Polarization (ODNP) capture water dynamics across micrometer length scales in sub-seconds to sub-nanometers in tens of picoseconds, respectively. We find that classical models, such as the Stokes-Einstein and Mackie-Meares relations, cannot capture water diffusion across a wide range of PEO concentrations, but that free volume theory can. Our study shows that PEO concentration affects macroscopic water diffusion by enhancing the water structure and altering free volume. ODNP experiments reveal that water diffusivity near PEO is slower than in the bulk in dilute solutions, previously not recognized by macroscopic transport measurements, but the two populations converge above the polymer overlap concentration. Molecular dynamics simulations reveal that the reduction in water diffusivity occurs with enhanced tetrahedral structuring near PEO. Broadly, we find that PEO does not simply behave like a physical obstruction but directly modifies water's structural and dynamic properties. Thus, even in simple PEO solutions, molecular scale structuring and the impact of polymer interfaces is essential to capturing water diffusion, an observation with important implications for water transport through structurally complex membrane materials.
Collapse
Affiliation(s)
- Joshua D Moon
- Materials Department, University of California Santa Barbara California 93106 USA
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Thomas R Webber
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Dennis Robinson Brown
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Peter M Richardson
- Materials Department, University of California Santa Barbara California 93106 USA
| | - Thomas M Casey
- Department of Chemistry and Biochemistry, University of California Santa Barbara California 93106 USA
| | - Rachel A Segalman
- Materials Department, University of California Santa Barbara California 93106 USA
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - M Scott Shell
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
| | - Songi Han
- Department of Chemical Engineering, University of California Santa Barbara California 93106 USA
- Department of Chemistry and Biochemistry, University of California Santa Barbara California 93106 USA
| |
Collapse
|
5
|
Yang Q, Zhao J, Dreyer F, Krüger D, Chu A, Kern M, Blümich B, Anders J. A chip-based C-band ODNP platform. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 358:107603. [PMID: 38142565 DOI: 10.1016/j.jmr.2023.107603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 11/24/2023] [Accepted: 11/28/2023] [Indexed: 12/26/2023]
Abstract
In this paper, we present a chip-based C-band ODNP platform centered around an NMR-on-a-chip transceiver and a printed microwave (MW) Alderman-Grant (AG) coil with a broadband tunable frequency range of 528MHz. The printable ODNP probe is optimized for a high input-power-to-magnetic-field conversion-efficiency, achieving a measured ODNP enhancement factor of -151 at microwave power levels of 33.3dBm corresponding to 2.1W. NMR measurements with and without microwave irradiation verify the functionality and the state-of-the-art performance of the proposed ODNP platform. The wide tuning range of the system allows for indirect measurements of the EPR signal of the DNP agent by sweeping the microwave excitation frequency and recording the resulting NMR signal. This feature can, e.g., be used to detect line broadening of the DNP agent. Moreover, we demonstrate experimentally that the wide tuning range of the new ODNP platform can be used to perform multi-tone microwave excitation for further signal enhancement: Using a 10mM TEMPOL solution, we improved the enhancement by a factor of two.
Collapse
Affiliation(s)
- Qing Yang
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany
| | - Jianyu Zhao
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany
| | - Frederik Dreyer
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany
| | - Daniel Krüger
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany; John A. Paulson School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge, 02138, United States
| | - Anh Chu
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany
| | - Michal Kern
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany
| | - Bernhard Blümich
- Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringerweg 2, Aachen, 52074, Germany
| | - Jens Anders
- Institute of Smart Sensors, University of Stuttgart, Pfafenwaldring 47, Stuttgart, 70569, Germany; Center for Integrated Quantum Science and Technology (IQ(ST)), Stuttgart, Germany; Institute for Microelectronics Stuttgart (IMS CHIPS), Stuttgart, Germany.
| |
Collapse
|
6
|
Dunleavy KM, Li T, Milshteyn E, Jaufer AM, Walker SA, Fanucci GE. Charge Distribution Patterns of IA 3 Impact Conformational Expansion and Hydration Diffusivity of the Disordered Ensemble. J Phys Chem B 2023; 127:9734-9746. [PMID: 37936402 DOI: 10.1021/acs.jpcb.3c06170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
IA3 is a 68 amino acid natural peptide/protein inhibitor of yeast aspartic proteinase A (YPRA) that is intrinsically disordered in solution with induced N-terminal helicity when in the protein complex with YPRA. Based on the intrinsically disordered protein (IDP) parameters of fractional net charge (FNC), net charge density per residue (NCPR), and charge patterning (κ), the two domains of IA3 are defined to occupy different domains within conformationally based subclasses of IDPs, thus making IA3 a bimodal domain IDP. Site-directed spin labeling (SDSL) electron paramagnetic resonance (EPR) spectroscopy and low-field Overhauser dynamic nuclear polarization (ODNP) spectroscopy results show that these two domains possess different degrees of compaction and hydration diffusivity behavior. This work suggests that SDSL EPR line shapes, analyzed in terms of their local tumbling volume (VL), provide insights into the compaction of the unstructured IDP ensemble in solution and that protein sequence and net charge distribution patterns within a conformational subclass can impact bound water hydration dynamics, thus possibly offering an alternative thermodynamic property that can encode conformational binding and behavior of IDPs and liquid-liquid phase separations.
Collapse
Affiliation(s)
- Katie M Dunleavy
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Tianyan Li
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Eugene Milshteyn
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Afnan M Jaufer
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| | - Shamon A Walker
- Materials Research Laboratory, University of California, Santa Barbara, California 93106, United States
| | - Gail E Fanucci
- Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, Florida 32611, United States
| |
Collapse
|
7
|
Whitcomb K, Warncke K. Oligomeric and Fibrillar α-Synuclein Display Persistent Dynamics and Compressibility under Controlled Confinement. ACS Chem Neurosci 2023; 14:3905-3912. [PMID: 37861459 PMCID: PMC10623556 DOI: 10.1021/acschemneuro.3c00470] [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: 07/14/2023] [Accepted: 09/26/2023] [Indexed: 10/21/2023] Open
Abstract
The roles of α-synuclein in neurotransmitter release in brain neurons and in the Parkinson's disease condition have challenged comprehensive description. To gain insight into molecular mechanistic properties that actuate α-synuclein function and dysfunction, the coupled protein and solvent dynamics of oligomer and fibril forms of human α-synuclein are examined in a low-temperature system that allows control of confinement and localization of a motionally sensitive electron paramagnetic resonance spin probe in the coupled solvent-protein regions. The rotational mobility of the spin probe resolves two distinct α-synuclein-associated solvent components for oligomers and fibrils, as for globular proteins, but with dramatically higher fluidities at each temperature, that are comparable to low-confinement, aqueous-cryosolvent mesophases. In contrast to the temperature-independent volumes of the solvent phases that surround globular and condensate-forming proteins, the higher-fluidity mesophase volume of α-synuclein oligomers and fibrils decreases with decreasing temperature, signaling a compression of this phase. This unique property and thermal hysteresis in the mobilities and component weights, together with previous high-resolution structural characterizations, suggest a model in which the dynamically disordered C-terminal domain of α-synuclein creates a compressible phase that maintains high fluidity under confinement. Robust dynamics and compressibility are fundamental molecular mechanical properties of α-synuclein oligomers and fibrils, which may contribute to dysfunction and inform about function.
Collapse
Affiliation(s)
- Katie
Lynn Whitcomb
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
| | - Kurt Warncke
- Department of Physics, Emory University, Atlanta, Georgia 30322, United States
| |
Collapse
|
8
|
Sakamoto K, Hamachi T, Miyokawa K, Tateishi K, Uesaka T, Kurashige Y, Yanai N. Polarizing agents beyond pentacene for efficient triplet dynamic nuclear polarization in glass matrices. Proc Natl Acad Sci U S A 2023; 120:e2307926120. [PMID: 37871226 PMCID: PMC10622900 DOI: 10.1073/pnas.2307926120] [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: 05/11/2023] [Accepted: 09/08/2023] [Indexed: 10/25/2023] Open
Abstract
Triplet dynamic nuclear polarization (triplet-DNP) is a technique that can obtain high nuclear polarization under moderate conditions. However, in order to obtain practically useful polarization, large single crystals doped with a polarizing agent must be strictly oriented with respect to the magnetic field to sharpen the electron spin resonance (ESR) spectra, which is a fatal problem that prevents its application to truly useful biomolecular targets. Instead of this conventional physical approach of controlling crystal orientation, here, we propose a chemical approach, i.e., molecular design of polarizing agents; pentacene molecules, the most typical triplet-DNP polarizing agent, are modified so as to make the triplet electron distribution wider and more isotropic without loss of the triplet polarization. The thiophene-modified pentacene exhibits a sharper and stronger ESR spectrum than the parent pentacene, and state-of-the-art quantum chemical calculations revealed that the direction of the spin polarization is altered by the modification with thiophene moieties and the size of D and E parameters are reduced from parent pentacene due to the partial delocalization of spin densities on the thiophene moieties. The triplet-DNP with the new polarizing agent successfully exceeds the previous highest 1H polarization of glassy materials by a factor of 5. This demonstrates the feasibility of a polarizing agent that can surpass pentacene, the best polarizing agent for more than 30 y since triplet-DNP was first reported, in the unoriented state. This work provides a pathway toward practically useful high nuclear polarization of various biomolecules by triplet-DNP.
Collapse
Affiliation(s)
- Keita Sakamoto
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka819-0395, Japan
| | - Tomoyuki Hamachi
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka819-0395, Japan
| | - Katsuki Miyokawa
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto606-8502, Japan
| | - Kenichiro Tateishi
- Cluster for Pioneering Research, RIKEN, RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama351-0198, Japan
| | - Tomohiro Uesaka
- Cluster for Pioneering Research, RIKEN, RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama351-0198, Japan
| | - Yuki Kurashige
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto606-8502, Japan
- Japan Science and Technology Agency-Fusion Oriented REsearch for disruptive Science and Technology, Kawaguchi, Saitama332-0012, Japan
| | - Nobuhiro Yanai
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Fukuoka819-0395, Japan
- Japan Science and Technology Agency-Fusion Oriented REsearch for disruptive Science and Technology, Kawaguchi, Saitama332-0012, Japan
| |
Collapse
|
9
|
Teucher M, Kucher S, Timachi MH, Wilson CB, Śmiłowicz D, Stoll R, Metzler-Nolte N, Sherwin MS, Han S, Bordignon E. Spectroscopically Orthogonal Spin Labels in Structural Biology at Physiological Temperatures. J Phys Chem B 2023; 127:6668-6674. [PMID: 37490415 PMCID: PMC10405217 DOI: 10.1021/acs.jpcb.3c04497] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/08/2023] [Indexed: 07/27/2023]
Abstract
Electron paramagnetic resonance spectroscopy (EPR) is mostly used in structural biology in conjunction with pulsed dipolar spectroscopy (PDS) methods to monitor interspin distances in biomacromolecules at cryogenic temperatures both in vitro and in cells. In this context, spectroscopically orthogonal spin labels were shown to increase the information content that can be gained per sample. Here, we exploit the characteristic properties of gadolinium and nitroxide spin labels at physiological temperatures to study side chain dynamics via continuous wave (cw) EPR at X band, surface water dynamics via Overhauser dynamic nuclear polarization at X band and short-range distances via cw EPR at high fields. The presented approaches further increase the accessible information content on biomolecules tagged with orthogonal labels providing insights into molecular interactions and dynamic equilibria that are only revealed under physiological conditions.
Collapse
Affiliation(s)
- Markus Teucher
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
| | - Svetlana Kucher
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
- Department
of Physical Chemistry, University of Geneva, Genève 1211, Switzerland
| | - M. Hadi Timachi
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
| | - C. Blake Wilson
- Department
of Physics, University of California, Santa
Barbara, Santa
Barbara, California 93106, United States
- Institute
for Terahertz Science and Technology, University
of California, Santa Barbara, Santa
Barbara, California 93106, United States
| | - Dariusz Śmiłowicz
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
| | - Raphael Stoll
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
| | - Nils Metzler-Nolte
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
| | - Mark S. Sherwin
- Department
of Physics, University of California, Santa
Barbara, Santa
Barbara, California 93106, United States
- Institute
for Terahertz Science and Technology, University
of California, Santa Barbara, Santa
Barbara, California 93106, United States
| | - Songi Han
- Institute
for Terahertz Science and Technology, University
of California, Santa Barbara, Santa
Barbara, California 93106, United States
- Department
of Chemistry and Biochemistry, University
of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Enrica Bordignon
- Faculty
of Chemistry and Biochemistry, Ruhr University
of Bochum, Bochum 44801, Germany
- Department
of Physical Chemistry, University of Geneva, Genève 1211, Switzerland
| |
Collapse
|
10
|
Sezer D. The solid effect of dynamic nuclear polarization in liquids. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2023; 4:153-174. [PMID: 37904804 PMCID: PMC10583289 DOI: 10.5194/mr-4-153-2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 04/23/2023] [Indexed: 11/01/2023]
Abstract
The solid-state effect of dynamic nuclear polarization (DNP) is operative also in viscous liquids where the dipolar interaction between the electronic and nuclear spins is partially averaged. The proper way to quantify the degree of averaging, and thus calculate the efficiency of the effect, should be based on the time-correlation function of the dipolar interaction. Here we use the stochastic Liouville equation formalism to develop a general theoretical description of the solid effect in liquids. The derived expressions can be used with different dipolar correlations functions depending on the assumed motional model. At high magnetic fields, the theory predicts DNP enhancements at small offsets, far from the classical solid-effect positions that are displaced by one nuclear Larmor frequency from the electronic resonance. The predictions are in quantitative agreement with such enhancement peaks observed at 9.4 T . These non-canonical peaks are not due to thermal mixing or the cross effect but exactly follow the dispersive component of the EPR line.
Collapse
Affiliation(s)
- Deniz Sezer
- Institute of Physical and Theoretical Chemistry, Goethe University, 60438 Frankfurt am Main, Germany
| |
Collapse
|
11
|
DeStefano A, Nguyen M, Fredrickson GH, Han S, Segalman RA. Design of Soft Material Surfaces with Rationally Tuned Water Diffusivity. ACS CENTRAL SCIENCE 2023; 9:1019-1024. [PMID: 37252353 PMCID: PMC10214527 DOI: 10.1021/acscentsci.3c00208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Indexed: 05/31/2023]
Abstract
Water structure and dynamics can be key modulators of adsorption, separations, and reactions at soft material interfaces, but systematically tuning water environments in an aqueous, accessible, and functionalizable material platform has been elusive. This work leverages variations in excluded volume to control and measure water diffusivity as a function of position within polymeric micelles using Overhauser dynamic nuclear polarization spectroscopy. Specifically, a versatile materials platform consisting of sequence-defined polypeptoids simultaneously offers a route to controlling the functional group position and a unique opportunity to generate a water diffusivity gradient extending away from the polymer micelle core. These results demonstrate an avenue not only to rationally design the chemical and structural properties of polymer surfaces but also to design and tune the local water dynamics that, in turn, can adjust the local activity for solutes.
Collapse
Affiliation(s)
- Audra
J. DeStefano
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - My Nguyen
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Glenn H. Fredrickson
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
- Materials
Research Laboratory, University of California, Santa Barbara, California 93106, United States
- Department
of Materials, University of California, Santa Barbara, California 93106, United States
| | - Songi Han
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
- Department
of Chemistry and Biochemistry, University
of California, Santa Barbara, California 93106, United States
| | - Rachel A. Segalman
- Department
of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
- Materials
Research Laboratory, University of California, Santa Barbara, California 93106, United States
- Department
of Materials, University of California, Santa Barbara, California 93106, United States
- Department
of Chemistry and Biochemistry, University
of California, Santa Barbara, California 93106, United States
| |
Collapse
|
12
|
Robinson Brown DC, Webber TR, Jiao S, Rivera Mirabal DM, Han S, Shell MS. Relationships between Molecular Structural Order Parameters and Equilibrium Water Dynamics in Aqueous Mixtures. J Phys Chem B 2023; 127:4577-4594. [PMID: 37171393 DOI: 10.1021/acs.jpcb.3c00826] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Water's unique thermophysical properties and how it mediates aqueous interactions between solutes have long been interpreted in terms of its collective molecular structure. The seminal work of Errington and Debenedetti [Nature 2001, 409, 318-321] revealed a striking hierarchy of relationships among the thermodynamic, dynamic, and structural properties of water, motivating many efforts to understand (1) what measures of water structure are connected to different experimentally accessible macroscopic responses and (2) how many such structural metrics are adequate to describe the collective structural behavior of water. Diffusivity constitutes a particularly interesting experimentally accessible equilibrium property to investigate such relationships because advanced NMR techniques allow the measurement of bulk and local water dynamics in nanometer proximity to molecules and interfaces, suggesting the enticing possibility of measuring local diffusivities that report on water structure. Here, we apply statistical learning methods to discover persistent structure-dynamic correlations across a variety of simulated aqueous mixtures, from alcohol-water to polypeptoid-water systems. We investigate a variety of molecular water structure metrics and find that an unsupervised statistical learning algorithm (namely, sequential feature selection) identifies only two or three independent structural metrics that are sufficient to predict water self-diffusivity accurately. Surprisingly, the translational diffusivity of water across all mixed systems studied here is strongly correlated with a measure of tetrahedral order given by water's triplet angle distribution. We also identify a separate small number of structural metrics that well predict an important thermodynamic property, the excess chemical potential of an idealized methane-sized hydrophobe in water. Ultimately, we offer a Bayesian method of inferring water structure by using only structure-dynamics linear regression models with experimental Overhauser dynamic nuclear polarization (ODNP) measurements of water self-diffusivity. This study thus quantifies the relationships among several distinct structural order parameters in water and, through statistical learning, reveals the potential to leverage molecular structure to predict fundamental thermophysical properties. In turn, these findings suggest a framework for solving the inverse problem of inferring water's molecular structure using experimental measurements such as ODNP studies that probe local water properties.
Collapse
Affiliation(s)
| | - Thomas R Webber
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Sally Jiao
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Daniela M Rivera Mirabal
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
13
|
Singlet fission as a polarized spin generator for dynamic nuclear polarization. Nat Commun 2023; 14:1056. [PMID: 36859419 PMCID: PMC9977948 DOI: 10.1038/s41467-023-36698-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 02/09/2023] [Indexed: 03/03/2023] Open
Abstract
Singlet fission (SF), converting a singlet excited state into a spin-correlated triplet-pair state, is an effective way to generate a spin quintet state in organic materials. Although its application to photovoltaics as an exciton multiplier has been extensively studied, the use of its unique spin degree of freedom has been largely unexplored. Here, we demonstrate that the spin polarization of the quintet multiexcitons generated by SF improves the sensitivity of magnetic resonance of water molecules through dynamic nuclear polarization (DNP). We form supramolecular assemblies of a few pentacene chromophores and use SF-born quintet spins to achieve DNP of water-glycerol, the most basic biological matrix, as evidenced by the dependence of nuclear polarization enhancement on magnetic field and microwave power. Our demonstration opens a use of SF as a polarized spin generator in bio-quantum technology.
Collapse
|
14
|
Milani J, Saenz F, Roussel C, Ansermet JP. Heterogeneous Overhauser-DNP on 1 H dominated by scalar coupling in aqueous solution. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2023; 61:180-183. [PMID: 36269065 DOI: 10.1002/mrc.5321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 10/01/2022] [Accepted: 10/19/2022] [Indexed: 06/16/2023]
Abstract
The Overhauser Dynamic Nuclear Polarization (O-DNP) of 1 H nuclei usually involves a dipolar coupling with the polarizing agent, whereas scalar coupling via hyperfine interactions are more common with 13 C nuclei. Here, we show a scalar-coupling dominated 1 H O-DNP, using polyaniline as a heterogeneous polarizing agent in an aqueous solution.
Collapse
Affiliation(s)
- Jonas Milani
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| | - Felipe Saenz
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| | - Christophe Roussel
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
- Section of Chemistry and Chemical Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| | - Jean-Philippe Ansermet
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, CH-1015, Switzerland
| |
Collapse
|
15
|
Eills J, Budker D, Cavagnero S, Chekmenev EY, Elliott SJ, Jannin S, Lesage A, Matysik J, Meersmann T, Prisner T, Reimer JA, Yang H, Koptyug IV. Spin Hyperpolarization in Modern Magnetic Resonance. Chem Rev 2023; 123:1417-1551. [PMID: 36701528 PMCID: PMC9951229 DOI: 10.1021/acs.chemrev.2c00534] [Citation(s) in RCA: 64] [Impact Index Per Article: 64.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Indexed: 01/27/2023]
Abstract
Magnetic resonance techniques are successfully utilized in a broad range of scientific disciplines and in various practical applications, with medical magnetic resonance imaging being the most widely known example. Currently, both fundamental and applied magnetic resonance are enjoying a major boost owing to the rapidly developing field of spin hyperpolarization. Hyperpolarization techniques are able to enhance signal intensities in magnetic resonance by several orders of magnitude, and thus to largely overcome its major disadvantage of relatively low sensitivity. This provides new impetus for existing applications of magnetic resonance and opens the gates to exciting new possibilities. In this review, we provide a unified picture of the many methods and techniques that fall under the umbrella term "hyperpolarization" but are currently seldom perceived as integral parts of the same field. Specifically, before delving into the individual techniques, we provide a detailed analysis of the underlying principles of spin hyperpolarization. We attempt to uncover and classify the origins of hyperpolarization, to establish its sources and the specific mechanisms that enable the flow of polarization from a source to the target spins. We then give a more detailed analysis of individual hyperpolarization techniques: the mechanisms by which they work, fundamental and technical requirements, characteristic applications, unresolved issues, and possible future directions. We are seeing a continuous growth of activity in the field of spin hyperpolarization, and we expect the field to flourish as new and improved hyperpolarization techniques are implemented. Some key areas for development are in prolonging polarization lifetimes, making hyperpolarization techniques more generally applicable to chemical/biological systems, reducing the technical and equipment requirements, and creating more efficient excitation and detection schemes. We hope this review will facilitate the sharing of knowledge between subfields within the broad topic of hyperpolarization, to help overcome existing challenges in magnetic resonance and enable novel applications.
Collapse
Affiliation(s)
- James Eills
- Institute
for Bioengineering of Catalonia, Barcelona
Institute of Science and Technology, 08028Barcelona, Spain
| | - Dmitry Budker
- Johannes
Gutenberg-Universität Mainz, 55128Mainz, Germany
- Helmholtz-Institut,
GSI Helmholtzzentrum für Schwerionenforschung, 55128Mainz, Germany
- Department
of Physics, UC Berkeley, Berkeley, California94720, United States
| | - Silvia Cavagnero
- Department
of Chemistry, University of Wisconsin, Madison, Madison, Wisconsin53706, United States
| | - Eduard Y. Chekmenev
- Department
of Chemistry, Integrative Biosciences (IBio), Karmanos Cancer Institute
(KCI), Wayne State University, Detroit, Michigan48202, United States
- Russian
Academy of Sciences, Moscow119991, Russia
| | - Stuart J. Elliott
- Molecular
Sciences Research Hub, Imperial College
London, LondonW12 0BZ, United Kingdom
| | - Sami Jannin
- Centre
de RMN à Hauts Champs de Lyon, Université
de Lyon, CNRS, ENS Lyon, Université Lyon 1, 69100Villeurbanne, France
| | - Anne Lesage
- Centre
de RMN à Hauts Champs de Lyon, Université
de Lyon, CNRS, ENS Lyon, Université Lyon 1, 69100Villeurbanne, France
| | - Jörg Matysik
- Institut
für Analytische Chemie, Universität
Leipzig, Linnéstr. 3, 04103Leipzig, Germany
| | - Thomas Meersmann
- Sir
Peter Mansfield Imaging Centre, University Park, School of Medicine, University of Nottingham, NottinghamNG7 2RD, United Kingdom
| | - Thomas Prisner
- Institute
of Physical and Theoretical Chemistry and Center of Biomolecular Magnetic
Resonance, Goethe University Frankfurt, , 60438Frankfurt
am Main, Germany
| | - Jeffrey A. Reimer
- Department
of Chemical and Biomolecular Engineering, UC Berkeley, and Materials Science Division, Lawrence Berkeley National
Laboratory, Berkeley, California94720, United States
| | - Hanming Yang
- Department
of Chemistry, University of Wisconsin, Madison, Madison, Wisconsin53706, United States
| | - Igor V. Koptyug
- International Tomography Center, Siberian
Branch of the Russian Academy
of Sciences, 630090Novosibirsk, Russia
| |
Collapse
|
16
|
Hecker F, Fries L, Hiller M, Chiesa M, Bennati M. 17 O Hyperfine Spectroscopy Reveals Hydration Structure of Nitroxide Radicals in Aqueous Solutions. Angew Chem Int Ed Engl 2023; 62:e202213700. [PMID: 36399425 PMCID: PMC10107301 DOI: 10.1002/anie.202213700] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 11/14/2022] [Accepted: 11/17/2022] [Indexed: 11/19/2022]
Abstract
The hydration structure of nitroxide radicals in aqueous solutions is elucidated by advanced 17 O hyperfine (hf) spectroscopy with support of quantum chemical calculations and MD simulations. A piperidine and a pyrrolidine-based nitroxide radical are compared and show clear differences in the preferred directionality of H-bond formation. We demonstrate that these scenarios are best represented in 17 O hf spectra, where in-plane coordination over σ ${\sigma }$ -type H-bonding leads to little spin density transfer on the water oxygen and small hf couplings, whereas π ${{\rm \pi }}$ -type perpendicular coordination generates much larger hf couplings. Quantitative analysis of the spectra based on MD simulations and DFT predicted hf parameters is consistent with a distribution of close solvating water molecules, in which directionality is influenced by subtle steric effects of the ring and the methyl group substituents.
Collapse
Affiliation(s)
- Fabian Hecker
- Research Group EPR spectroscopy, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany
| | - Lisa Fries
- Research Group EPR spectroscopy, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Current address: Center for Biostructural Imaging of Neurodegeneration, Medical Center Göttingen, Von-Siebold-Straße 3a, 37075, Göttingen, Germany.,NMR Signal Enhancement Group, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany
| | - Markus Hiller
- Research Group EPR spectroscopy, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Current address: Isotope Technologies Dresden, Rossendorfer Ring 42, 01328, Dresden, Germany
| | - Mario Chiesa
- Department of Chemistry, University of Torino, Via Giuria 9, 10125, Torino, Italy
| | - Marina Bennati
- Research Group EPR spectroscopy, Max Planck Institute for Multidisciplinary Sciences, Am Fassberg 11, 37077, Göttingen, Germany.,Department of Chemistry, Georg August University Göttingen, Tammanstrasse 2, 37077, Göttingen, Germany
| |
Collapse
|
17
|
Hong Y, Najafi S, Casey T, Shea JE, Han SI, Hwang DS. Hydrophobicity of arginine leads to reentrant liquid-liquid phase separation behaviors of arginine-rich proteins. Nat Commun 2022; 13:7326. [PMID: 36443315 PMCID: PMC9705477 DOI: 10.1038/s41467-022-35001-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 11/14/2022] [Indexed: 11/29/2022] Open
Abstract
Intrinsically disordered proteins rich in cationic amino acid groups can undergo Liquid-Liquid Phase Separation (LLPS) in the presence of charge-balancing anionic counterparts. Arginine and Lysine are the two most prevalent cationic amino acids in proteins that undergo LLPS, with arginine-rich proteins observed to undergo LLPS more readily than lysine-rich proteins, a feature commonly attributed to arginine's ability to form stronger cation-π interactions with aromatic groups. Here, we show that arginine's ability to promote LLPS is independent of the presence of aromatic partners, and that arginine-rich peptides, but not lysine-rich peptides, display re-entrant phase behavior at high salt concentrations. We further demonstrate that the hydrophobicity of arginine is the determining factor giving rise to the reentrant phase behavior and tunable viscoelastic properties of the dense LLPS phase. Controlling arginine-induced reentrant LLPS behavior using temperature and salt concentration opens avenues for the bioengineering of stress-triggered biological phenomena and drug delivery systems.
Collapse
Affiliation(s)
- Yuri Hong
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Saeed Najafi
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Thomas Casey
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA, 93106, USA
| | - Joan-Emma Shea
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA, 93106, USA.
| | - Song-I Han
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, CA, 93106, USA.
- Department of Chemical Engineering, University of California, Santa Barbara, CA, 93106, USA.
| | - Dong Soo Hwang
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea.
| |
Collapse
|
18
|
Li W, Whitcomb KL, Warncke K. Confinement dependence of protein-associated solvent dynamics around different classes of proteins, from the EPR spin probe perspective. Phys Chem Chem Phys 2022; 24:23919-23928. [PMID: 36165617 PMCID: PMC10371532 DOI: 10.1039/d2cp03047k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Protein function is modulated by coupled solvent fluctuations, subject to the degree of confinement from the surroundings. To identify universal features of the external confinement effect, the temperature dependence of the dynamics of protein-associated solvent over 200-265 K for proteins representative of different classes and sizes is characterized by using the rotational correlation time (detection bandwidth, 10-10-10-7 s) of the electron paramagnetic resonance (EPR, X-band) spin probe, TEMPOL, which is restricted to regions vicinal to protein in frozen aqueous solution. Weak (protein surrounded by aqueous-dimethylsulfoxide cryosolvent mesodomain) and strong (no added crysolvent) conditions of ice boundary confinement are imposed. The panel of soluble proteins represents large and small oligomeric (ethanolamine ammonia-lyase, 488 kDa; streptavidin, 52.8 kDa) and monomeric (myoglobin, 16.7 kDa) globular proteins, an intrinsically disordered protein (IDP, β-casein, 24.0 kDa), an unstructured peptide (protamine, 4.38 kDa) and a small peptide with partial backbone order (amyloid-β residues 1-16, 1.96 kDa). Expanded and condensate structures of β-casein and protamine are resolved by the spin probe under weak and strong confinement, respectively. At each confinement condition, the soluble globular proteins display common T-dependences of rotational correlation times and normalized weights, for two mobility components, protein-associated domain, PAD, and surrounding mesodomain. Strong confinement induces a detectable PAD component and emulation of globular protein T-dependence by the amyloid-β peptide. Confinement uniformly impacts soluble globular protein PAD dynamics, and is therefore a generic control parameter for modulation of soluble globular protein function.
Collapse
Affiliation(s)
- Wei Li
- Department of Physics, Emory University, Atlanta, Georgia, 30322.
| | | | - Kurt Warncke
- Department of Physics, Emory University, Atlanta, Georgia, 30322.
| |
Collapse
|
19
|
Matsumoto N, Nishimura K, Kimizuka N, Nishiyama Y, Tateishi K, Uesaka T, Yanai N. Proton Hyperpolarization Relay from Nanocrystals to Liquid Water. J Am Chem Soc 2022; 144:18023-18029. [DOI: 10.1021/jacs.2c07518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Naoto Matsumoto
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Koki Nishimura
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Nobuo Kimizuka
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yusuke Nishiyama
- NanoCrystallography Unit, RIKEN-JEOL Collaboration Center, Tsurumi, Yokohama, Kanagawa 230-0045, Japan
- JEOL RESONANCE Inc., 3-1-2 Musashino, Akishima, Tokyo 196-8558, Japan
| | - Kenichiro Tateishi
- Cluster for Pioneering Research, RIKEN, RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - Tomohiro Uesaka
- Cluster for Pioneering Research, RIKEN, RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama 351-0198, Japan
| | - Nobuhiro Yanai
- Department of Applied Chemistry, Graduate School of Engineering, Center for Molecular Systems, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- PRESTO and FOREST, JST, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
20
|
Gizatullin B, Mattea C, Shikhov I, Arns C, Stapf S. Modeling Molecular Interactions with Wetting and Non-Wetting Rock Surfaces by Combining Electron Paramagnetic Resonance and NMR Relaxometry. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:11033-11053. [PMID: 36047994 DOI: 10.1021/acs.langmuir.2c01681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Three types of natural rocks─Bentheimer and Berea sandstones, as well as Liège Chalk─have been aged by immersion in a bitumen solution for extended periods of time in two steps, changing the surface conditions from water-wet to oil-wet. NMR relaxation dispersion measurements were carried out on water and oil constituents, with saturated and aromatic molecules considered individually. In order to separate the different relaxation mechanisms discussed in the literature, 1H and 19F relaxation times were compared to 2H for fully deuterated liquids: while 2H relaxes predominantly by quadrupolar coupling, which is an intramolecular process, the remaining nuclei relax by dipolar coupling, which potentially consists of intra- and intermolecular contributions. The wettability change becomes evident in an increase of relaxation rates for oil and a corresponding decrease for water. However, this expected behavior dominates only for the spin-lattice relaxation rate R1 at very low field strengths and for the spin-spin relaxation rate R2, while high-field longitudinal relaxation shows a much weaker or even reverse trend. This is attributed in part to a change of radical concentration on the pore surface upon coverage of the native rock surface by bitumen as well as by the change of surface chemistry and roughness. EPR and DNP measurements quantify the change of volume vs surface radical concentration in the rocks, and an improved understanding of the role of relaxation via paramagnetic centers is obtained. By means of comparing different fluids and nuclei in combination with a defined wettability change of natural rocks, a refined model for molecular dynamics in conjunction with NMR relaxation dispersion is proposed.
Collapse
Affiliation(s)
- Bulat Gizatullin
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| | - Carlos Mattea
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| | - Igor Shikhov
- School of Minerals and Energy Resources Engineering, Univ. of New South Wales, Sydney, NSW 2052, Australia
| | - Christoph Arns
- School of Minerals and Energy Resources Engineering, Univ. of New South Wales, Sydney, NSW 2052, Australia
| | - Siegfried Stapf
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| |
Collapse
|
21
|
Lee G, Kageyama Y, Takeda S. Site-Selective Spin-Probe with a Photocleavable Macrocyclic Linker for Measuring the Dynamics of Water Surrounding a Liposomal Assembly. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2022. [DOI: 10.1246/bcsj.20220027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Gyeorye Lee
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Yoshiyuki Kageyama
- Faculty of Science, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| | - Sadamu Takeda
- Faculty of Science, Hokkaido University, Kita-10 Nishi-8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan
| |
Collapse
|
22
|
Pham P, Mandal R, Qi C, Hilty C. Interfacing Liquid State Hyperpolarization Methods with NMR Instrumentation. JOURNAL OF MAGNETIC RESONANCE OPEN 2022; 10-11:100052. [PMID: 35530721 PMCID: PMC9070690 DOI: 10.1016/j.jmro.2022.100052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Advances in liquid state hyperpolarization methods have enabled new applications of high-resolution NMR spectroscopy. Utilizing strong signal enhancements from hyperpolarization allows performing NMR spectroscopy at low concentration, or with high time resolution. Making use of the high, but rapidly decaying hyperpolarization in the liquid state requires new techniques to interface hyperpolarization equipment with liquid state NMR spectrometers. This article highlights rapid injection, high resolution NMR spectroscopy with hyperpolarization produced by the techniques of dissolution dynamic nuclear polarization (D-DNP) and para-hydrogen induced polarization (PHIP). These are popular, albeit not the only methods to produce high polarization levels for liquid samples. Gas and liquid driven sample injection techniques are compatible with both of these hyperpolarization methods. The rapid sample injection techniques are combined with adapted NMR experiments working in a single, or small number of scans. They expand the application of liquid state hyperpolarization to spins with comparably short relaxation times, provide enhanced control over sample conditions, and allow for mixing experiments to study reactions in real time.
Collapse
|
23
|
Li W, Nforneh B, Whitcomb KL, Warncke K. Resolution and characterization of confinement- and temperature-dependent dynamics in solvent phases that surround proteins in frozen aqueous solution by using spin-probe EPR spectroscopy. Methods Enzymol 2022; 666:25-57. [PMID: 35465922 DOI: 10.1016/bs.mie.2022.02.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Spin probe electron paramagnetic resonance spectroscopy is applied to characterize the dynamics of concentric hydration and mesophase solvent domains that surround proteins within the ice boundary in frozen aqueous solutions. The solvent dynamics are tuned by variation of temperature (190-265K) and by the degree of ice boundary confinement, which is modulated by the volume of added cryosolvent (0-~50Å separation distance from protein surface). Goals are to: (1) characterize the protein-coupled solvent dynamics on correlation time scales of ~10-10<τ<10-7s, and spatial scales from protein surface to periphery of the surrounding solution, from the perspective of a free, small-molecule (~7Å diameter) probe, and (2) reveal properties of the solvent-protein coupling that can be correlated with protein functions, that are measureable under the same conditions. Rotational mobility of the nitroxide spin probe, TEMPOL, resolves and tracks two solvent components, the protein-associated domain (PAD; akin to hydration layer) and surrounding mesodomain, through their distinct temperature- and confinement-dependent values of τ and normalized weight. Detailed protocols are described for simulation of two-component nitroxide EPR spectra, which are categorized by line shape regime and guided by a library of template spectra and simulation parameters derived from two model soluble globular proteins. The order-disorder transition in the PAD, which is a universal feature of protein-coupled solvent dynamics, provides a well-defined, tunable property for elucidating mechanism in solvent-protein-function dynamical coupling. The low-temperature mesodomain system and EPR spin probe method are generally applicable to reveal solvent contributions to a broad range of macromolecule-mediated biological processes.
Collapse
Affiliation(s)
- Wei Li
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Benjamen Nforneh
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Katie L Whitcomb
- Department of Physics, Emory University, Atlanta, GA, United States
| | - Kurt Warncke
- Department of Physics, Emory University, Atlanta, GA, United States.
| |
Collapse
|
24
|
Cheney DJ, Wedge CJ. Sample volume effects in optical overhauser dynamic nuclear polarization. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 337:107170. [PMID: 35240365 DOI: 10.1016/j.jmr.2022.107170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Revised: 02/13/2022] [Accepted: 02/16/2022] [Indexed: 06/14/2023]
Abstract
The optical dynamic nuclear polarization (DNP) method has been proposed as an alternative to microwave pumping as a hyperpolarization method for solution-state NMR studies. Using continuous laser illumination to photogenerate triplet states in the presence of a persistent radical produces chemically-induced dynamic electron polarization (CIDEP) via the radical-triplet pair mechanism (RTPM), with cross-relaxation transferring this to nuclear hyperpolarization via an Overhauser mechanism. Numerical simulations have previously indicated that reducing the sample volume while maintaining a constant optical density can significantly increase the NMR signal enhancement, due to the larger steady-state concentration of triplets obtained. Here we provide the first experimental confirmation of these effects, producing a nearly five-fold increase in the optical DNP enhancement factor just by reducing the sample volume with optimal dye and radical concentrations adjusted for each optical path length. The results are supported with an in depth analysis of volume effects in the numerical model, with which they are in good qualitative agreement. These important observations will impact on the future development of the technique, with particular significance for attempts to apply DNP methods to increase sensitivity for volume-limited biological samples.
Collapse
Affiliation(s)
- Daniel J Cheney
- Department of Chemical Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, United Kingdom
| | - Christopher J Wedge
- Department of Chemical Sciences, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, United Kingdom.
| |
Collapse
|
25
|
Jiao S, Rivera Mirabal DM, DeStefano AJ, Segalman RA, Han S, Shell MS. Sequence Modulates Polypeptoid Hydration Water Structure and Dynamics. Biomacromolecules 2022; 23:1745-1756. [PMID: 35274944 DOI: 10.1021/acs.biomac.1c01687] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We use molecular dynamics simulations to investigate the effect of polypeptoid sequence on the structure and dynamics of its hydration waters. Polypeptoids provide an excellent platform to study small-molecule hydration in disordered polymers, as they can be precisely synthesized with a variety of sidechain chemistries. We examine water behavior near a set of peptoid oligomers in which the number and placement of nonpolar versus polar sidechains are systematically varied. To do this, we leverage a new computational workflow enabling accurate sampling of polypeptoid conformations. We find that the hydration waters are less dense, are more tetrahedral, and have slower dynamics compared to bulk water. The magnitude of these shifts increases with the number of nonpolar groups. We also find that shifts in the water structure and dynamics are strongly correlated, suggesting that experimental insight into the dynamics of hydration water obtained by Overhauser dynamic nuclear polarization (ODNP) also contains information about water structural properties. We then demonstrate the ability of ODNP to probe site-specific dynamics of hydration water near these model peptoid systems.
Collapse
Affiliation(s)
- Sally Jiao
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Daniela M Rivera Mirabal
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States.,Department of Chemical Engineering, University of Puerto Rico, Mayagüez, Puerto Rico 00681, United States
| | - Audra J DeStefano
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| | - Rachel A Segalman
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States.,Department of Materials, University of California, Santa Barbara, California 93106, United States
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States.,Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, United States
| |
Collapse
|
26
|
Moon H, Collanton RP, Monroe JI, Casey TM, Shell MS, Han S, Scott SL. Evidence for Entropically Controlled Interfacial Hydration in Mesoporous Organosilicas. J Am Chem Soc 2022; 144:1766-1777. [PMID: 35041412 DOI: 10.1021/jacs.1c11342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
At aqueous interfaces, the distribution and dynamics of adsorbates are modulated by the behavior of interfacial water. Hydration of a hydrophobic surface can store entropy via the ordering of interfacial water, which contributes to the Gibbs energy of solute binding. However, there is little experimental evidence for the existence of such entropic reservoirs, and virtually no precedent for their rational design in systems involving extended interfaces. In this study, two series of mesoporous silicas were modified in distinct ways: (1) progressively deeper thermal dehydroxylation, via condensation of surface silanols, and (2) increasing incorporation of nonpolar organic linkers into the silica framework. Both approaches result in decreasing average surface polarity, manifested in a blue-shift in the fluorescence of an adsorbed dye. For the inorganic silicas, hydrogen-bonding of water becomes less extensive as the number of surface silanols decreases. Overhauser dynamic nuclear polarization (ODNP) relaxometry indicates enhanced surface water diffusivity, reflecting a loss of enthalpic hydration. In contrast, organosilicas show a monotonic decrease in surface water diffusivity with decreasing polarity, reflecting enhanced hydrophobic hydration. Molecular dynamics simulations predict increased tetrahedrality of interfacial water for the organosilicas, implying increased ordering near the nm-size organic domains (relative to inorganic silicas, which necessarily lack such domains). These findings validate the prediction that hydrophobic hydration at interfaces is controlled by the microscopic length scale of the hydrophobic regions. They further suggest that the hydration thermodynamics of structurally heterogeneous silica surfaces can be tuned to promote adsorption, which in turn tunes the selectivity in catalytic reactions.
Collapse
Affiliation(s)
- Hyunjin Moon
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Ryan P Collanton
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Jacob I Monroe
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Thomas M Casey
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States.,Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Susannah L Scott
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States.,Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| |
Collapse
|
27
|
Fujiwara S, Matsumoto N, Nishimura K, Kimizuka N, Tateishi K, Uesaka T, Yanai N. Triplet Dynamic Nuclear Polarization of Guest Molecules through Induced Fit in a Flexible Metal–Organic Framework**. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202115792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Saiya Fujiwara
- Department of Applied Chemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka Nishi-ku, Fukuoka 819-0395 Japan
| | - Naoto Matsumoto
- Department of Applied Chemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka Nishi-ku, Fukuoka 819-0395 Japan
| | - Koki Nishimura
- Department of Applied Chemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka Nishi-ku, Fukuoka 819-0395 Japan
| | - Nobuo Kimizuka
- Department of Applied Chemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka Nishi-ku, Fukuoka 819-0395 Japan
| | - Kenichiro Tateishi
- Cluster for Pioneering Research RIKEN RIKEN Nishina Center for Accelerator-Based Science Wako, Saitama 351-0198 Japan
| | - Tomohiro Uesaka
- Cluster for Pioneering Research RIKEN RIKEN Nishina Center for Accelerator-Based Science Wako, Saitama 351-0198 Japan
| | - Nobuhiro Yanai
- Department of Applied Chemistry Graduate School of Engineering Center for Molecular Systems (CMS) Kyushu University 744 Moto-oka Nishi-ku, Fukuoka 819-0395 Japan
- PRESTO JST Honcho 4-1-8 Kawaguchi, Saitama 332-0012 Japan
| |
Collapse
|
28
|
Gizatullin B, Mattea C, Stapf S. Three mechanisms of room temperature dynamic nuclear polarization occur simultaneously in an ionic liquid. Phys Chem Chem Phys 2022; 24:27004-27008. [DOI: 10.1039/d2cp03437a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
For the first time, several mechanisms of dynamic nuclear polarization, namely Overhauser, solid effect and cross effect/thermal mixing, have been identified in an ionic liquid with a nitroxide radical at ambient temperatures.
Collapse
Affiliation(s)
- Bulat Gizatullin
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| | - Carlos Mattea
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| | - Siegfried Stapf
- FG Technische Physik II/Polymerphysik, Technische Universität Ilmenau, D-98684 Ilmenau, Germany
| |
Collapse
|
29
|
Fujiwara S, Matsumoto N, Nishimura K, Kimizuka N, Tateishi K, Uesaka T, Yanai N. Triplet Dynamic Nuclear Polarization of Guest Molecules through Induced Fit in a Flexible Metal-Organic Framework. Angew Chem Int Ed Engl 2021; 61:e202115792. [PMID: 34935275 DOI: 10.1002/anie.202115792] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Indexed: 11/12/2022]
Abstract
Dynamic nuclear polarization utilizing photoexcited triplet electrons (triplet-DNP) has great potential for room-temperature hyperpolarization of nuclear spins. However, the polarization transfer to molecules of interest remains a challenge due to the fast spin relaxation and weak interaction with target molecules at room temperature in conventional host materials. Here, we demonstrate the first example of DNP of guest molecules in a porous material at around room temperature by utilizing the induced-fit-type structural transformation of a crystalline yet flexible metal-organic framework (MOF). In contrast to the usual hosts, 1 H spin-lattice relaxation time becomes longer by accommodating a pharmaceutical model target 5-fluorouracil as the flexible MOF changes its structure upon guest accommodation to maximize the host-guest interactions. Combined with triplet-DNP and cross-polarization (CP), this system realizes an enhanced 19 F-NMR signal of guest target molecules.
Collapse
Affiliation(s)
- Saiya Fujiwara
- Kyushu University: Kyushu Daigaku, Department of Applied Chemistry, JAPAN
| | - Naoto Matsumoto
- Kyushu University: Kyushu Daigaku, Department of Applied Chemistry, JAPAN
| | - Koki Nishimura
- Kyushu University: Kyushu Daigaku, Department of Applied Chemistry, JAPAN
| | - Nobuo Kimizuka
- Kyushu University: Kyushu Daigaku, Department of Applied Chemistry, JAPAN
| | | | - Tomohiro Uesaka
- RIKEN: Rikagaku Kenkyujo, Cluster for Pioneering Research, JAPAN
| | - Nobuhiro Yanai
- Kyushu University, Department of Chemistry and Biochemistry, 744 Moto-oka, Nishi-ku, 819-0395, Fukuoka, JAPAN
| |
Collapse
|
30
|
Dai D, Wang X, Liu Y, Yang XL, Glaubitz C, Denysenkov V, He X, Prisner T, Mao J. Room-temperature dynamic nuclear polarization enhanced NMR spectroscopy of small biological molecules in water. Nat Commun 2021; 12:6880. [PMID: 34824218 PMCID: PMC8616939 DOI: 10.1038/s41467-021-27067-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 11/01/2021] [Indexed: 11/15/2022] Open
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is a powerful and popular technique for probing the molecular structures, dynamics and chemical properties. However the conventional NMR spectroscopy is bottlenecked by its low sensitivity. Dynamic nuclear polarization (DNP) boosts NMR sensitivity by orders of magnitude and resolves this limitation. In liquid-state this revolutionizing technique has been restricted to a few specific non-biological model molecules in organic solvents. Here we show that the carbon polarization in small biological molecules, including carbohydrates and amino acids, can be enhanced sizably by in situ Overhauser DNP (ODNP) in water at room temperature and at high magnetic field. An observed connection between ODNP 13C enhancement factor and paramagnetic 13C NMR shift has led to the exploration of biologically relevant heterocyclic compound indole. The QM/MM MD simulation underscores the dynamics of intermolecular hydrogen bonds as the driving force for the scalar ODNP in a long-living radical-substrate complex. Our work reconciles results obtained by DNP spectroscopy, paramagnetic NMR and computational chemistry and provides new mechanistic insights into the high-field scalar ODNP.
Collapse
Affiliation(s)
- Danhua Dai
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
- Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
| | - Xianwei Wang
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China
- College of Science, Zhejiang University of Technology, Hangzhou, Zhejiang, 310023, China
| | - Yiwei Liu
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China
| | - Xiao-Liang Yang
- Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Clemens Glaubitz
- Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
- Institute of Biophysical Chemistry, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
| | - Vasyl Denysenkov
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
- Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
| | - Xiao He
- Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200062, China.
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai, 200062, China.
| | - Thomas Prisner
- Institute of Physical and Theoretical Chemistry, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
- Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany
| | - Jiafei Mao
- Center for Biomolecular Magnetic Resonance, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany.
- Institute of Biophysical Chemistry, Goethe University Frankfurt, 60438, Frankfurt am Main, Germany.
| |
Collapse
|
31
|
Fehling P, Buckenmaier K, Dobrynin SA, Morozov DA, Polienko YF, Khoroshunova YV, Borozdina Y, Mayer P, Engelmann J, Scheffler K, Angelovski G, Kirilyuk IA. The effects of nitroxide structure upon 1H Overhauser dynamic nuclear polarization efficacy at ultralow-field. J Chem Phys 2021; 155:144203. [PMID: 34654311 DOI: 10.1063/5.0064342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The efficacy in 1H Overhauser dynamic nuclear polarization in liquids at ultralow magnetic field (ULF, B0 = 92 ± 0.8 µT) and polarization field (Bp = 1-10 mT) was studied for a broad variety of 26 different spin probes. Among others, piperidine, pyrrolidine, and pyrroline radicals specifically synthesized for this study, along with some well-established commercially available nitroxides, were investigated. Isotope-substituted variants, some sterically shielded reduction-resistant nitroxides, and some biradicals were included in the measurements. The maximal achievable enhancement, Emax, and the radio frequency power, P1/2, needed for reaching Emax/2 were measured. Physico-chemical features such as molecular weight, spectral linewidth, heterocyclic structure, different types of substituents, deuteration, and 15N-labeling as well as the difference between monoradicals and biradicals were investigated. For the unmodified nitroxide radicals, the Emax values correlate with the molecular weight. The P1/2 values correlate with the spectral linewidth and are additionally influenced by the type of substituents neighboring the nitroxide group. The nitroxide biradicals with high intramolecular spin-spin coupling show low performance. Nitroxides enriched with 15N and/or 2H afford significantly higher |Emax| and require lower power to do so, compared to their unmodified counterparts containing at natural abundance predominantly 14N and 1H. The results allow for a correlation of chemical features with physical hyperpolarization-related properties and indicate that small nitroxides with narrow spectral lines have clear advantages for the use in Overhauser dynamic nuclear polarization experiments. Perdeuteration and 15N-labeling can be used to additionally boost the spin probe performance.
Collapse
Affiliation(s)
- Paul Fehling
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Kai Buckenmaier
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Sergey A Dobrynin
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Denis A Morozov
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Yuliya F Polienko
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Yulia V Khoroshunova
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| | - Yulia Borozdina
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Philipp Mayer
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Jörn Engelmann
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Klaus Scheffler
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Goran Angelovski
- Max Planck Institute for Biological Cybernetics, 72076 Tübingen, Germany
| | - Igor A Kirilyuk
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, 630090 Novosibirsk, Russia
| |
Collapse
|
32
|
Kircher R, Hasse H, Münnemann K. High Flow-Rate Benchtop NMR Spectroscopy Enabled by Continuous Overhauser DNP. Anal Chem 2021; 93:8897-8905. [PMID: 34137586 DOI: 10.1021/acs.analchem.1c01118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Analysis of a fast-flowing liquid with NMR spectroscopy is challenging because short residence times in the magnetic field of the spectrometer result in inefficient polarization buildup and thus poor signal intensity. This is particularly problematic for benchtop NMR spectrometers because of their compact design. Therefore, in the present work, different methods to counteract this prepolarization problem in benchtop NMR spectroscopy were studied experimentally. The tests were carried out with an equimolar acetonitrile + water mixture flowing through a capillary with a 0.25 mm inner diameter at flow rates up to 2.00 mL min-1, corresponding to mean velocities of up to 0.7 m s-1. Established approaches gave only poor results at high flow rates, namely, using a prepolarization magnet, using a loopy flow cell, and using a T1 relaxation agent. To overcome this, signal enhancement by Overhauser dynamic nuclear polarization (ODNP) was used, which is based on polarization transfer from unpaired electron spins to nuclear spins and happens on very short time scales, resulting in high signal enhancements, also in fast-flowing liquids. A corresponding setup was developed and used for the studies: the line leading to the 1 T benchtop NMR spectrometer first passes through a fixed bed with a radical matrix placed in a Halbach magnet equipped with a microwave cavity to facilitate the spin transfer. With this ODNP setup, excellent results were obtained even for the highest studied flow rates. This shows that ODNP is an enabler for fast-flow benchtop NMR spectroscopy.
Collapse
Affiliation(s)
- Raphael Kircher
- Laboratory of Engineering Thermodynamics (LTD), University of Kaiserslautern, D-67663 Kaiserslautern, Germany
| | - Hans Hasse
- Laboratory of Engineering Thermodynamics (LTD), University of Kaiserslautern, D-67663 Kaiserslautern, Germany
| | - Kerstin Münnemann
- Laboratory of Engineering Thermodynamics (LTD), University of Kaiserslautern, D-67663 Kaiserslautern, Germany
| |
Collapse
|
33
|
Keller T, Maly T. Overhauser dynamic nuclear polarization (ODNP)-enhanced two-dimensional proton NMR spectroscopy at low magnetic fields. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2021; 2:117-128. [PMID: 35465650 PMCID: PMC9030190 DOI: 10.5194/mr-2-117-2021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/23/2021] [Indexed: 04/16/2023]
Abstract
The majority of low-field Overhauser dynamic nuclear polarization (ODNP) experiments reported so far have been 1D NMR experiments to study molecular dynamics and in particular hydration dynamics. In this work, we demonstrate the application of ODNP-enhanced 2D J-resolved (JRES) spectroscopy to improve spectral resolution beyond the limit imposed by the line broadening introduced by the paramagnetic polarizing agent. Using this approach, we are able to separate the overlapping multiplets of ethyl crotonate into a second dimension and clearly identify each chemical site individually. Crucial to these experiments is interleaved spectral referencing, a method introduced to compensate for temperature-induced field drifts over the course of the NMR acquisition. This method does not require additional hardware such as a field-frequency lock, which is especially challenging when designing compact systems.
Collapse
Affiliation(s)
- Timothy J. Keller
- Bridge12 Technologies Inc., 37 Loring Drive, Framingham, MA 01702, USA
| | - Thorsten Maly
- Bridge12 Technologies Inc., 37 Loring Drive, Framingham, MA 01702, USA
| |
Collapse
|
34
|
Hamachi T, Nishimura K, Kouno H, Kawashima Y, Tateishi K, Uesaka T, Kimizuka N, Yanai N. Porphyrins as Versatile, Aggregation-Tolerant, and Biocompatible Polarizing Agents for Triplet Dynamic Nuclear Polarization of Biomolecules. J Phys Chem Lett 2021; 12:2645-2650. [PMID: 33689350 DOI: 10.1021/acs.jpclett.1c00294] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Triplet dynamic nuclear polarization (triplet-DNP) achieves nuclear spin polarization at moderate temperatures by using spin polarization of photoexcited triplet electrons. The applications of triplet-DNP for biomolecules have been hampered because acenes, the only polarizing agents used so far, tend to aggregate and lose their polarization in biomolecular matrices. Here, we report for the first time use of porphyrins as polarizing agents of triplet-DNP and propose a new concept of aggregation-tolerant polarizing agents. Sodium salts of tetrakis(4-carboxyphenyl)porphyrin (TCPPNa) can be dispersed in amorphous as well as crystalline biomolecular matrices, and importantly, it can generate polarized triplet electrons even in a slightly aggregated state. Triplet-DNP of crystalline erythritol containing slightly aggregated TCPPNa can achieve more than 120-fold signal enhancement. Because TCPPNa is also the first biocompatible triplet-DNP polarizing agent, this work provides a crucial step forward for the biological and medical applications of triplet-DNP.
Collapse
Affiliation(s)
- Tomoyuki Hamachi
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Koki Nishimura
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hironori Kouno
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yusuke Kawashima
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Kenichiro Tateishi
- Cluster for Pioneering Research, RIKEN, RIKEN Nishina Center for Accelerator-Based Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Tomohiro Uesaka
- Cluster for Pioneering Research, RIKEN, RIKEN Nishina Center for Accelerator-Based Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Nobuo Kimizuka
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Nobuhiro Yanai
- Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka 819-0395, Japan
- JST-PRESTO, Honcho 4-1-8, Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
35
|
Abstract
Nuclear magnetic resonance at low field strength is an insensitive spectroscopic technique, precluding portable applications with small sample volumes, such as needed for biomarker detection in body fluids. Here we report a compact double resonant chip stack system that implements in situ dynamic nuclear polarisation of a 130 nL sample volume, achieving signal enhancements of up to - 60 w.r.t. the thermal equilibrium level at a microwave power level of 0.5 W. This work overcomes instrumental barriers to the use of NMR detection for point-of-care applications.
Collapse
|
36
|
Keller TJ, Maly T. Overhauser dynamic nuclear polarization (ODNP)-enhanced two-dimensional proton NMR spectroscopy at low magnetic fields. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2021. [PMID: 35465650 DOI: 10.5281/zenodo.4479048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 04/24/2023]
Abstract
The majority of low-field Overhauser dynamic nuclear polarization (ODNP) experiments reported so far have been 1D NMR experiments to study molecular dynamics and in particular hydration dynamics. In this work, we demonstrate the application of ODNP-enhanced 2D J-resolved (JRES) spectroscopy to improve spectral resolution beyond the limit imposed by the line broadening introduced by the paramagnetic polarizing agent. Using this approach, we are able to separate the overlapping multiplets of ethyl crotonate into a second dimension and clearly identify each chemical site individually. Crucial to these experiments is interleaved spectral referencing, a method introduced to compensate for temperature-induced field drifts over the course of the NMR acquisition. This method does not require additional hardware such as a field-frequency lock, which is especially challenging when designing compact systems.
Collapse
Affiliation(s)
- Timothy J Keller
- Bridge12 Technologies Inc., 37 Loring Drive, Framingham, MA 01702, USA
| | - Thorsten Maly
- Bridge12 Technologies Inc., 37 Loring Drive, Framingham, MA 01702, USA
| |
Collapse
|
37
|
Dale MW, Cheney DJ, Vallotto C, Wedge CJ. Viscosity effects on optically generated electron and nuclear spin hyperpolarization. Phys Chem Chem Phys 2020; 22:28173-28182. [PMID: 33291127 DOI: 10.1039/d0cp04012f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Spin hyperpolarization can dramatically increase signal intensities in magnetic resonance experiments, providing either improved bulk sensitivity or additional spectroscopic detail through selective enhancements. While typical hyperpolarization approaches have utilized microwave irradiation, one emerging route is the use of optically generated triplet states. We report an investigation into the effects of solution viscosity on radical-triplet pair interactions, propose a new standard for quantification of the hyperpolarization in EPR experiments, and demonstrate a significant increase in the optically generated 1H NMR signal enhancement upon addition of glycerol to aqueous solutions.
Collapse
Affiliation(s)
- Matthew W Dale
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | | | | | | |
Collapse
|
38
|
Überrück T, Adams M, Granwehr J, Blümich B. A compact X-Band ODNP spectrometer towards hyperpolarized 1H spectroscopy. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 314:106724. [PMID: 32278774 DOI: 10.1016/j.jmr.2020.106724] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 03/19/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
The demand for compact benchtop NMR systems that can resolve chemical shift differences in the ppm to sub-ppm range is growing. However due to material and size restrictions these magnets are limited in field strength and thus in signal intensity and quality. The implementation of standard hyperpolarization techniques is a next step in an effort to boost the signal. Here we present a compact Overhauser Dynamic Nuclear Polarization (ODNP) setup with a permanent magnet that can resolve 1H chemical shift differences in the ppm range. The assembly of the setup and its components are described in detail, and the functionality of the setup is demonstrated experimentally with ODNP enhanced relaxation measurements yielding a maximal enhancement of -140 for an aqueous 4-hydroxy-TEMPO solution. Additionally, 1H spectroscopic resolution and significant enhancements are demonstrated on acetic acid as a solvent.
Collapse
Affiliation(s)
- Till Überrück
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany
| | - Michael Adams
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany
| | - Josef Granwehr
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany; Forschungszentrum Jülich, Institut für Energie- und Klimaforschung - Grundlagen der Elektrochemie (IEK-9), 52425 Jülich, Germany
| | - Bernhard Blümich
- RWTH Aachen University, Institut für Technische und Makromolekulare Chemie, Worringerweg 2, 52074 Aachen, Germany.
| |
Collapse
|
39
|
Keller TJ, Laut AJ, Sirigiri J, Maly T. High-resolution Overhauser dynamic nuclear polarization enhanced proton NMR spectroscopy at low magnetic fields. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2020; 313:106719. [PMID: 32217425 PMCID: PMC7172445 DOI: 10.1016/j.jmr.2020.106719] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/13/2020] [Accepted: 03/15/2020] [Indexed: 05/11/2023]
Abstract
Dynamic nuclear polarization (DNP) has gained large interest due to its ability to increase signal intensities in nuclear magnetic resonance (NMR) experiments by several orders of magnitude. Currently, DNP is typically used to enhance high-field, solid-state NMR experiments. However, the method is also capable of dramatically increasing the observed signal intensities in solution-state NMR spectroscopy. In this work, we demonstrate the application of Overhauser dynamic nuclear polarization (ODNP) spectroscopy at an NMR frequency of 14.5 MHz (0.35 T) to observe DNP-enhanced high-resolution NMR spectra of small molecules in solutions. Using a compact hybrid magnet with integrated shim coils to improve the magnetic field homogeneity we are able to routinely obtain proton linewidths of less than 4 Hz and enhancement factors >30. The excellent field resolution allows us to perform chemical-shift resolved ODNP experiments on ethyl crotonate to observe proton J-coupling. Furthermore, recording high-resolution ODNP-enhanced NMR spectra of ethylene glycol allows us to characterize the microwave induced sample heating in-situ, by measuring the separation of the OH and CH2 proton peaks.
Collapse
Affiliation(s)
| | | | | | - Thorsten Maly
- Bridge12 Technologies, 37 Loring Drive, Framingham, MA 01702, USA
| |
Collapse
|
40
|
Monroe J, Barry M, DeStefano A, Aydogan Gokturk P, Jiao S, Robinson-Brown D, Webber T, Crumlin EJ, Han S, Shell MS. Water Structure and Properties at Hydrophilic and Hydrophobic Surfaces. Annu Rev Chem Biomol Eng 2020; 11:523-557. [PMID: 32169001 DOI: 10.1146/annurev-chembioeng-120919-114657] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The properties of water on both molecular and macroscopic surfaces critically influence a wide range of physical behaviors, with applications spanning from membrane science to catalysis to protein engineering. Yet, our current understanding of water interfacing molecular and material surfaces is incomplete, in part because measurement of water structure and molecular-scale properties challenges even the most advanced experimental characterization techniques and computational approaches. This review highlights progress in the ongoing development of tools working to answer fundamental questions on the principles that govern the interactions between water and surfaces. One outstanding and critical question is what universal molecular signatures capture the hydrophobicity of different surfaces in an operationally meaningful way, since traditional macroscopic hydrophobicity measures like contact angles fail to capture even basic properties of molecular or extended surfaces with any heterogeneity at the nanometer length scale. Resolving this grand challenge will require close interactions between state-of-the-art experiments, simulations, and theory, spanning research groups and using agreed-upon model systems, to synthesize an integrated knowledge of solvation water structure, dynamics, and thermodynamics.
Collapse
Affiliation(s)
- Jacob Monroe
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Mikayla Barry
- Department of Materials, University of California, Santa Barbara, California 93106, USA
| | - Audra DeStefano
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Pinar Aydogan Gokturk
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Sally Jiao
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Dennis Robinson-Brown
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Thomas Webber
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| | - Ethan J Crumlin
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA; .,Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106, USA;
| |
Collapse
|
41
|
Han CT, Song J, Chan T, Pruett C, Han S. Electrostatic Environment of Proteorhodopsin Affects the pKa of Its Buried Primary Proton Acceptor. Biophys J 2020; 118:1838-1849. [PMID: 32197061 DOI: 10.1016/j.bpj.2020.02.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/27/2020] [Accepted: 02/27/2020] [Indexed: 01/18/2023] Open
Abstract
The protonation state of embedded charged residues in transmembrane proteins (TMPs) can control the onset of protein function. It is understood that interactions between an embedded charged residue and other charged or polar residues in the moiety would influence its pKa, but how the surrounding environment in which the TMP resides affects the pKa of these residues is unclear. Proteorhodopsin (PR), a light-responsive proton pump from marine bacteria, was used as a model to examine externally accessible factors that tune the pKa of its embedded charged residue, specifically its primary proton acceptor D97. The pKa of D97 was compared between PR reconstituted in liposomes with different net headgroup charges and equilibrated in buffer with different ion concentrations. For PR reconstituted in net positively charged compared to net negatively charged liposomes in low-salt buffer solutions, a drop of the apparent pKa from 7.6 to 5.6 was observed, whereas intrinsic pKa modeled with surface pH calculated from Gouy-Chapman predictions found an opposite trend for the pKa change, suggesting that surface pH does not account for the main changes observed in the apparent pKa. This difference in the pKa of D97 observed from PR reconstituted in oppositely charged liposome environments disappeared when the NaCl concentration was increased to 150 mM. We suggest that protein-intrinsic structural properties must play a role in adjusting the local microenvironment around D97 to affect its pKa, as corroborated with observations of changes in protein side-chain and hydration dynamics around the E-F loop of PR. Understanding the effect of externally controllable factors in tuning the pKa of TMP-embedded charged residues is important for bioengineering and biomedical applications relying on TMP systems, in which the onset of functions can be controlled by the protonation state of embedded residues.
Collapse
Affiliation(s)
- Chung-Ta Han
- Department of Chemical Engineering, University of California, Santa Barbara, California
| | - Jichao Song
- Department of Chemical Engineering, University of California, Santa Barbara, California
| | - Tristan Chan
- Department of Chemistry, University of California, Santa Barbara, California
| | - Christine Pruett
- Department of Chemical Engineering, University of California, Santa Barbara, California
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California; Department of Chemistry, University of California, Santa Barbara, California.
| |
Collapse
|
42
|
Levien M, Hiller M, Tkach I, Bennati M, Orlando T. Nitroxide Derivatives for Dynamic Nuclear Polarization in Liquids: The Role of Rotational Diffusion. J Phys Chem Lett 2020; 11:1629-1635. [PMID: 32003568 PMCID: PMC7307959 DOI: 10.1021/acs.jpclett.0c00270] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 01/31/2020] [Indexed: 06/07/2023]
Abstract
Polarization transfer efficiency in liquid-state dynamic nuclear polarization (DNP) depends on the interaction between polarizing agents (PAs) and target nuclei modulated by molecular motions. We show how translational and rotational diffusion differently affect the DNP efficiency. These contributions were disentangled by measuring 1H-DNP enhancements of toluene and chloroform doped with nitroxide derivatives at 0.34 T as a function of either the temperature or the size of the PA. The results were employed to analyze 13C-DNP data at higher fields, where the polarization transfer is also driven by the Fermi contact interaction. In this case, bulky nitroxide PAs perform better than the small TEMPONE radical due to structural fluctuations of the ring conformation. These findings will help in designing PAs with features specifically optimized for liquid-state DNP at various magnetic fields.
Collapse
Affiliation(s)
- M. Levien
- Research
Group EPR Spectroscopy, Max Planck Institute
for Biophysical Chemistry, Göttingen 37077, Germany
- Department
of Chemistry, Georg-August University, Göttingen 37077, Germany
| | - M. Hiller
- Research
Group EPR Spectroscopy, Max Planck Institute
for Biophysical Chemistry, Göttingen 37077, Germany
| | - I. Tkach
- Research
Group EPR Spectroscopy, Max Planck Institute
for Biophysical Chemistry, Göttingen 37077, Germany
| | - M. Bennati
- Research
Group EPR Spectroscopy, Max Planck Institute
for Biophysical Chemistry, Göttingen 37077, Germany
- Department
of Chemistry, Georg-August University, Göttingen 37077, Germany
| | - T. Orlando
- Research
Group EPR Spectroscopy, Max Planck Institute
for Biophysical Chemistry, Göttingen 37077, Germany
| |
Collapse
|
43
|
Judge PT, Sesti EL, Price LE, Albert BJ, Alaniva N, Saliba EP, Halbritter T, Sigurdsson ST, Kyei GB, Barnes AB. Dynamic Nuclear Polarization with Electron Decoupling in Intact Human Cells and Cell Lysates. J Phys Chem B 2020; 124:2323-2330. [DOI: 10.1021/acs.jpcb.9b10494] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Patrick T. Judge
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
- Department of Biochemistry, Biophysics & Structural Biology, Washington University in St. Louis, St. Louis, Missouri 63110, United States
| | - Erika L. Sesti
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Lauren E. Price
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Brice J. Albert
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Nicholas Alaniva
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Edward P. Saliba
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Thomas Halbritter
- Department of Chemistry, Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavik, Iceland
| | - Snorri Th. Sigurdsson
- Department of Chemistry, Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavik, Iceland
| | - George B. Kyei
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63130, United States
- Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana,
Legon, Accra 02233, Ghana
| | - Alexander B. Barnes
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| |
Collapse
|
44
|
Lindemann WR, Evans ED, Mijalis AJ, Saouaf OM, Pentelute BL, Ortony JH. Quantifying residue-specific conformational dynamics of a highly reactive 29-mer peptide. Sci Rep 2020; 10:2597. [PMID: 32054898 PMCID: PMC7018720 DOI: 10.1038/s41598-020-59047-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/22/2020] [Indexed: 11/19/2022] Open
Abstract
Understanding structural transitions within macromolecules remains an important challenge in biochemistry, with important implications for drug development and medicine. Insight into molecular behavior often requires residue-specific dynamics measurement at micromolar concentrations. We studied MP01-Gen4, a library peptide selected to rapidly undergo bioconjugation, by using electron paramagnetic resonance (EPR) to measure conformational dynamics. We mapped the dynamics of MP01-Gen4 with residue-specificity and identified the regions involved in a structural transformation related to the conjugation reaction. Upon reaction, the conformational dynamics of residues near the termini slow significantly more than central residues, indicating that the reaction induces a structural transition far from the reaction site. Arrhenius analysis demonstrates a nearly threefold decrease in the activation energy of conformational diffusion upon reaction (8.0 kBT to 3.4 kBT), which occurs across the entire peptide, independently of residue position. This novel approach to EPR spectral analysis provides insight into the positional extent of disorder and the nature of the energy landscape of a highly reactive, intrinsically disordered library peptide before and after conjugation.
Collapse
Affiliation(s)
- William R Lindemann
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
| | - Ethan D Evans
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, 02139, United States
| | - Alexander J Mijalis
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
- Department of Genetics, Harvard Medical School, Boston, Massachusetts, 02115, USA
| | - Olivia M Saouaf
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
- Department of Materials Science and Engineering, Stanford University, 496 Lomita Mall, Stanford, California, 94305, United States
| | - Bradley L Pentelute
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States
| | - Julia H Ortony
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts, 02139, United States.
| |
Collapse
|
45
|
Cheney DJ, Wedge CJ. Optically-generated Overhauser dynamic nuclear polarization: A numerical analysis. J Chem Phys 2020; 152:034202. [DOI: 10.1063/1.5133408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Daniel J. Cheney
- Department of Chemical Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom
| | - Christopher J. Wedge
- Department of Chemical Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom
| |
Collapse
|
46
|
Dey A, Banerjee A. Unusual Overhauser Dynamic Nuclear Polarization Behavior of Fluorinated Alcohols at Room Temperature. J Phys Chem B 2019; 123:10463-10469. [PMID: 31714083 DOI: 10.1021/acs.jpcb.9b08144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The structure of fluorinated alcohols is a matter of considerable interest in view of wide-ranging biomolecular applications. The microheterogeneity of fluorinated alcohols in the liquid state, in particular, has been a matter of debate and discussion in recent years using experimental and theoretical methods, including neutron or X-ray diffraction, as well as density functional theory (DFT) and molecular dynamics (MD) simulations. Here, we show that 1H and 19F Overhauser dynamic nuclear polarization (ODNP) buildup curves in solution state at room temperature show unusual behavior that could offer a novel approach to investigate the structural heterogeneity and dynamics of such homogeneous liquids with improved sensitivity. A detailed analysis of multiexponential ODNP buildup curves as a function of microwave irradiation time is shown to evidence microheterogeneity in such systems. Experimental ODNP buildup rates are interpreted using simple motional models that yield the motional correlation times of the relevant species in solution. It may be emphasized that this information is not available from standard approaches of high-resolution nuclear magnetic resonance (NMR) spectroscopy. While the present study focuses on fluorinated alcohols, it is to be anticipated that this approach would be valuable in the study of molecular assemblies in the solution state, including peptides, surfactant systems, etc.
Collapse
Affiliation(s)
- Arnab Dey
- MRI-MRS Centre and Department of Chemistry , Indian Institute of Technology-Madras , Chennai 600036 , Tamil Nadu , India
| | - Abhishek Banerjee
- MRI-MRS Centre and Department of Chemistry , Indian Institute of Technology-Madras , Chennai 600036 , Tamil Nadu , India
| |
Collapse
|
47
|
Tao M, Pandey NK, Barnes R, Han S, Langen R. Structure of Membrane-Bound Huntingtin Exon 1 Reveals Membrane Interaction and Aggregation Mechanisms. Structure 2019; 27:1570-1580.e4. [PMID: 31466833 DOI: 10.1016/j.str.2019.08.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/23/2019] [Accepted: 08/09/2019] [Indexed: 02/08/2023]
Abstract
Huntington's disease is caused by a polyQ expansion in the first exon of huntingtin (Httex1). Membrane interaction of huntingtin is of physiological and pathological relevance. Using electron paramagnetic resonance and Overhauser dynamic nuclear polarization, we find that the N-terminal residues 3-13 of wild-type Httex1(Q25) form a membrane-bound, amphipathic α helix. This helix is positioned in the interfacial region, where it is sensitive to membrane curvature and electrostatic interactions with head-group charges. Residues 14-22, which contain the first five residues of the polyQ region, are in a transition region that remains in the interfacial region without taking up a stable, α-helical structure. The remaining C-terminal portion is solvent exposed. The phosphomimetic S13D/S16D mutations, which are known to protect from toxicity, inhibit membrane binding and attenuate membrane-mediated aggregation of mutant Httex1(Q46) due to electrostatic repulsion. Targeting the N-terminal membrane anchor using post-translational modifications or specific binders could be a potential means to reduce aggregation and toxicity in vivo.
Collapse
Affiliation(s)
- Meixin Tao
- Department of Neuroscience and Physiology, Department of Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Nitin K Pandey
- Department of Neuroscience and Physiology, Department of Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Ryan Barnes
- Department of Chemistry and Biochemistry, Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Songi Han
- Department of Chemistry and Biochemistry, Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Ralf Langen
- Department of Neuroscience and Physiology, Department of Biochemistry and Molecular Medicine, Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
| |
Collapse
|
48
|
Banerjee A, Dey A, Chandrakumar N. Motional Dynamics of Halogen-Bonded Complexes Probed by Low-Field NMR Relaxometry and Overhauser Dynamic Nuclear Polarization. Chem Asian J 2019; 14:2785-2789. [PMID: 31210020 DOI: 10.1002/asia.201900754] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/14/2019] [Indexed: 11/07/2022]
Abstract
Halogen bonding is a subject of considerable interest owing to wide-ranging chemical, materials and biological applications. The motional dynamics of halogen-bonded complexes play a pivotal role in comprehending the nature of the halogen-bonding interaction. However, not many attempts appear to have been made to shed light on the dynamical characteristics of halogen-bonded species. For the first time, we demonstrate here that the combination of low-field NMR relaxometry and Overhauser dynamic nuclear polarization (ODNP) makes it possible to obtain a cogent picture of the motional dynamics of halogen-bonded species. We discuss here the advantages of this combined approach. Low-field relaxometry allows us to infer the hydrodynamic radius and rotational correlation time, whereas ODNP probes the molecular translational correlation times (involving the substrate as well as the organic radical) with high sensitivity at low field.
Collapse
Affiliation(s)
- Abhishek Banerjee
- MRI-MRS Centre and Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India
| | - Arnab Dey
- MRI-MRS Centre and Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India
| | - N Chandrakumar
- MRI-MRS Centre and Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India
| |
Collapse
|
49
|
Judge PT, Sesti EL, Saliba EP, Alaniva N, Halbritter T, Sigurdsson ST, Barnes AB. Sensitivity analysis of magic angle spinning dynamic nuclear polarization below 6 K. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2019; 305:51-57. [PMID: 31212198 DOI: 10.1016/j.jmr.2019.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 05/28/2019] [Accepted: 05/30/2019] [Indexed: 06/09/2023]
Abstract
Dynamic nuclear polarization (DNP) improves signal-to-noise in nuclear magnetic resonance (NMR) spectroscopy. Signal-to-noise in NMR can be further improved with cryogenic sample cooling. Whereas MAS DNP is commonly performed between 25 and 110 K, sample temperatures below 6 K lead to further improvements in sensitivity. Here, we demonstrate that solid effect MAS DNP experiments at 6 K, using trityl, yield 3.2× more sensitivity compared to 90 K. Trityl with solid effect DNP at 6 K yields substantially more signal to noise than biradicals and cross effect DNP. We also characterize cross effect DNP with AMUPol and TEMTriPol-1 biradicals for DNP magic angle spinning at temperatures below 6 K and 7 Tesla. DNP enhancements determined from microwave on/off intensities are 253 from AMUPol and 49 from TEMTriPol-1. The higher thermal Boltzmann polarization at 6 K compared to 298 K, combined with these enhancements, should result in 10,000× signal gain for AMUPol and 2000× gain for TEMTriPol-1. However, we show that AMUPol reduces signal in the absence of microwaves by 90% compared to 41% by TEMTriPol-1 at 7 Tesla as the result of depolarization and other detrimental paramagnetic effects. AMUPol still yields the highest signal-to-noise improvement per unit time between the cross effect radicals due to faster polarization buildup (T1DNP = 4.3 s and 36 s for AMUPol and TEMTriPol-1, respectively). Overall, AMUPol results in 2.5× better sensitivity compared to TEMTriPol-1 in MAS DNP experiments performed below 6 K at 7 T. Trityl provides 6.0× more sensitivity than TEMTriPol-1 and 1.9× more than AMUPol at 6 K, thus yielding the greatest signal-to-noise per unit time among all three radicals. A DNP enhancement profile of TEMTriPol-1 recorded with a frequency-tunable custom-built gyrotron oscillator operating at 198 GHz is also included. It is determined that at 7 T below 6 K a microwave power level of 0.6 W incident on the sample is sufficient to saturate the cross effect mechanism using TEMTriPol-1, yet increasing the power level up to 5 W results in higher improvements in DNP sensitivity with AMUPol. These results indicate MAS DNP below 6 K will play a prominent role in ultra-sensitive NMR spectroscopy in the future.
Collapse
Affiliation(s)
- Patrick T Judge
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA; Department of Biochemistry, Biophysics & Structural Biology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Erika L Sesti
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
| | - Edward P Saliba
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
| | - Nicholas Alaniva
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA
| | - Thomas Halbritter
- Department of Chemistry, University of Iceland, Science Institute, Dunhaga 3, 107 Reykjavik, Iceland
| | - Snorri Th Sigurdsson
- Department of Chemistry, University of Iceland, Science Institute, Dunhaga 3, 107 Reykjavik, Iceland
| | - Alexander B Barnes
- Department of Chemistry, Washington University in St. Louis, One Brookings Drive, St. Louis, MO 63130, USA.
| |
Collapse
|
50
|
Dahanayake JN, Shahryari E, Roberts KM, Heikes ME, Kasireddy C, Mitchell-Koch KR. Protein Solvent Shell Structure Provides Rapid Analysis of Hydration Dynamics. J Chem Inf Model 2019; 59:2407-2422. [PMID: 30865440 DOI: 10.1021/acs.jcim.9b00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The solvation layer surrounding a protein is clearly an intrinsic part of protein structure-dynamics-function, and our understanding of how the hydration dynamics influences protein function is emerging. We have recently reported simulations indicating a correlation between regional hydration dynamics and the structure of the solvation layer around different regions of the enzyme Candida antarctica lipase B, wherein the radial distribution function (RDF) was used to calculate the pairwise entropy, providing a link between dynamics (diffusion) and thermodynamics (excess entropy) known as Rosenfeld scaling. Regions with higher RDF values/peaks in the hydration layer (the first peak, within 6 Å of the protein surface) have faster diffusion in the hydration layer. The finding thus hinted at a handle for rapid evaluation of hydration dynamics at different regions on the protein surface in molecular dynamics simulations. Such an approach may move the analysis of hydration dynamics from a specialized venture to routine analysis, enabling an informatics approach to evaluate the role of hydration dynamics in biomolecular function. This paper first confirms that the correlation between regional diffusive dynamics and hydration layer structure (via water center of mass around protein side-chain atom RDF) is observed as a general relationship across a set of proteins. Second, it seeks to devise an approach for rapid analysis of hydration dynamics, determining the minimum amount of information and computational effort required to get a reliable value of hydration dynamics from structural data in MD simulations based on the protein-water RDF. A linear regression model using the integral of the hydration layer in the water-protein RDF was found to provide statistically equivalent apparent diffusion coefficients at the 95% confidence level for a set of 92 regions within five different proteins. In summary, RDF analysis of 10 ns of data after simulation convergence is sufficient to accurately map regions of fast and slow hydration dynamics around a protein surface. Additionally, it is anticipated that a quick look at protein-water RDFs, comparing peak heights, will be useful to provide a qualitative ranking of regions of faster and slower hydration dynamics at the protein surface for rapid analysis when investigating the role of solvent dynamics in protein function.
Collapse
Affiliation(s)
- Jayangika N Dahanayake
- Department of Chemistry , Wichita State University , 1845 Fairmount Street , Wichita , Kansas 67260-0051 , United States
| | - Elaheh Shahryari
- Department of Chemistry , Wichita State University , 1845 Fairmount Street , Wichita , Kansas 67260-0051 , United States
| | - Kirsten M Roberts
- Department of Chemistry , Wichita State University , 1845 Fairmount Street , Wichita , Kansas 67260-0051 , United States
| | - Micah E Heikes
- Department of Chemistry , Wichita State University , 1845 Fairmount Street , Wichita , Kansas 67260-0051 , United States
| | - Chandana Kasireddy
- Department of Chemistry , Wichita State University , 1845 Fairmount Street , Wichita , Kansas 67260-0051 , United States
| | - Katie R Mitchell-Koch
- Department of Chemistry , Wichita State University , 1845 Fairmount Street , Wichita , Kansas 67260-0051 , United States
| |
Collapse
|