1
|
Jann C, Giofré S, Bhattacharjee R, Lemke EA. Cracking the Code: Reprogramming the Genetic Script in Prokaryotes and Eukaryotes to Harness the Power of Noncanonical Amino Acids. Chem Rev 2024. [PMID: 39120726 DOI: 10.1021/acs.chemrev.3c00878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024]
Abstract
Over 500 natural and synthetic amino acids have been genetically encoded in the last two decades. Incorporating these noncanonical amino acids into proteins enables many powerful applications, ranging from basic research to biotechnology, materials science, and medicine. However, major challenges remain to unleash the full potential of genetic code expansion across disciplines. Here, we provide an overview of diverse genetic code expansion methodologies and systems and their final applications in prokaryotes and eukaryotes, represented by Escherichia coli and mammalian cells as the main workhorse model systems. We highlight the power of how new technologies can be first established in simple and then transferred to more complex systems. For example, whole-genome engineering provides an excellent platform in bacteria for enabling transcript-specific genetic code expansion without off-targets in the transcriptome. In contrast, the complexity of a eukaryotic cell poses challenges that require entirely new approaches, such as striving toward establishing novel base pairs or generating orthogonally translating organelles within living cells. We connect the milestones in expanding the genetic code of living cells for encoding novel chemical functionalities to the most recent scientific discoveries, from optimizing the physicochemical properties of noncanonical amino acids to the technological advancements for their in vivo incorporation. This journey offers a glimpse into the promising developments in the years to come.
Collapse
Affiliation(s)
- Cosimo Jann
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- IMB Postdoc Programme (IPPro), 55128 Mainz, Germany
| | - Sabrina Giofré
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- IMB Postdoc Programme (IPPro), 55128 Mainz, Germany
| | - Rajanya Bhattacharjee
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- IMB International PhD Programme (IPP), 55128 Mainz, Germany
| | - Edward A Lemke
- Biocenter, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- Institute of Molecular Biology (IMB), 55128 Mainz, Germany
| |
Collapse
|
2
|
Grosskopf JD, Sidabras JW, Altenbach C, Anderson JR, Mett RR, Strangeway RA, Hyde JS, Hubbell WL, Lerch MT. A pressure-jump EPR system to monitor millisecond conformational exchange rates of spin-labeled proteins. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.07.593074. [PMID: 38766191 PMCID: PMC11100676 DOI: 10.1101/2024.05.07.593074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Site-directed spin labeling electron paramagnetic resonance (SDSL-EPR) using nitroxide spin labels is a well-established technology for mapping site-specific secondary and tertiary structure and for monitoring conformational changes in proteins of any degree of complexity, including membrane proteins, with high sensitivity. SDSL-EPR also provides information on protein dynamics in the time scale of ps-µs using continuous wave lineshape analysis and spin lattice relaxation time methods. However, the functionally important time domain of µs-ms, corresponding to large-scale protein motions, is inaccessible to those methods. To extend SDSL-EPR to the longer time domain, the perturbation method of pressure-jump relaxation is implemented. Here, we describe a complete high-pressure EPR system at Q-band for both static pressure and millisecond-timescale pressure-jump measurements on spin-labeled proteins. The instrument enables pressure jumps both up and down from any holding pressure, ranging from atmospheric pressure to the maximum pressure capacity of the system components (~3500 bar). To demonstrate the utility of the system, we characterize a local folding-unfolding equilibrium of T4 lysozyme. The results illustrate the ability of the system to measure thermodynamic and kinetic parameters of protein conformational exchange on the millisecond timescale.
Collapse
Affiliation(s)
- Julian D Grosskopf
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Jason W Sidabras
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Christian Altenbach
- Department of Chemistry and Biochemistry and Stein Eye Institute, University of California, Los Angeles, CA 90095, USA
| | - Jim R Anderson
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Richard R Mett
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Robert A Strangeway
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - James S Hyde
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Wayne L Hubbell
- Department of Chemistry and Biochemistry and Stein Eye Institute, University of California, Los Angeles, CA 90095, USA
| | - Michael T Lerch
- Department of Biophysics, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| |
Collapse
|
3
|
Jaufer AM, Bouhadana A, Kharrazizadeh A, Zhou M, Colina CM, Fanucci GE. Designing surface exposed sites on Bacillus subtilis lipase A for spin-labeling and hydration studies. Biophys Chem 2024; 308:107203. [PMID: 38382282 DOI: 10.1016/j.bpc.2024.107203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/09/2024] [Accepted: 02/15/2024] [Indexed: 02/23/2024]
Abstract
Spin-labeling with electron paramagnetic resonance spectroscopy (EPR) is a facile method for interrogating macromolecular flexibility, conformational changes, accessibility, and hydration. Within we present a computationally based approach for the rational selection of reporter sites in Bacillus subtilis lipase A (BSLA) for substitution to cysteine residues with subsequent modification with a spin-label that are expected to not significantly perturb the wild-type structure, dynamics, or enzymatic function. Experimental circular dichroism spectroscopy, Michaelis-Menten kinetic parameters and EPR spectroscopy data validate the success of this approach to computationally select reporter sites for future magnetic resonance investigations of hydration and hydration changes induced by polymer conjugation, tethering, immobilization, or amino acid substitution in BSLA. Analysis of molecular dynamic simulations of the impact of substitutions on the secondary structure agree well with experimental findings. We propose that this computationally guided approach for choosing spin-labeled EPR reporter sites, which evaluates relative surface accessibility coupled with hydrogen bonding occupancy of amino acids to the catalytic pocket via atomistic simulations, should be readily transferable to other macromolecular systems of interest including selecting sites for paramagnetic relaxation enhancement NMR studies, other spin-labeling EPR studies or any method requiring a tagging method where it is desirable to not alter enzyme stability or activity.
Collapse
Affiliation(s)
- Afnan M Jaufer
- Department of Chemistry, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA; George and Josephine Butler Polymer Research Laboratory, University of Florida, Gainesville, FL 32611, USA.
| | - Adam Bouhadana
- Department of Chemistry, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA.
| | - Amir Kharrazizadeh
- Department of Chemistry, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA.
| | - Mingwei Zhou
- Department of Chemistry, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA.
| | - Coray M Colina
- Department of Chemistry, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA; George and Josephine Butler Polymer Research Laboratory, University of Florida, Gainesville, FL 32611, USA; Department of Materials Science and Engineering, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA.
| | - Gail E Fanucci
- Department of Chemistry, University of Florida, PO BOX 117200, Gainesville, FL 32611, USA.
| |
Collapse
|
4
|
Bogetti X, Saxena S. Integrating Electron Paramagnetic Resonance Spectroscopy and Computational Modeling to Measure Protein Structure and Dynamics. Chempluschem 2024; 89:e202300506. [PMID: 37801003 DOI: 10.1002/cplu.202300506] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/05/2023] [Accepted: 10/06/2023] [Indexed: 10/07/2023]
Abstract
Electron paramagnetic resonance (EPR) has become a powerful probe of conformational heterogeneity and dynamics of biomolecules. In this Review, we discuss different computational modeling techniques that enrich the interpretation of EPR measurements of dynamics or distance restraints. A variety of spin labels are surveyed to provide a background for the discussion of modeling tools. Molecular dynamics (MD) simulations of models containing spin labels provide dynamical properties of biomolecules and their labels. These simulations can be used to predict EPR spectra, sample stable conformations and sample rotameric preferences of label sidechains. For molecular motions longer than milliseconds, enhanced sampling strategies and de novo prediction software incorporating or validated by EPR measurements are able to efficiently refine or predict protein conformations, respectively. To sample large-amplitude conformational transition, a coarse-grained or an atomistic weighted ensemble (WE) strategy can be guided with EPR insights. Looking forward, we anticipate an integrative strategy for efficient sampling of alternate conformations by de novo predictions, followed by validations by systematic EPR measurements and MD simulations. Continuous pathways between alternate states can be further sampled by WE-MD including all intermediate states.
Collapse
Affiliation(s)
- Xiaowei Bogetti
- Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15260, USA
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15260, USA
| |
Collapse
|
5
|
Heubach CA, Hasanbasri Z, Abdullin D, Reuter A, Korzekwa B, Saxena S, Schiemann O. Differentiating between Label and Protein Conformers in Pulsed Dipolar EPR Spectroscopy with the dHis-Cu 2+ (NTA) Motif. Chemistry 2023; 29:e202302541. [PMID: 37755452 DOI: 10.1002/chem.202302541] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 09/28/2023]
Abstract
Pulsed dipolar EPR spectroscopy (PDS) in combination with site-directed spin labeling is a powerful tool in structural biology. However, the commonly used spin labels are conjugated to biomolecules via rather long and flexible linkers, which hampers the translation of distance distributions into biomolecular conformations. In contrast, the spin label copper(II)-nitrilotriacetic acid [Cu2+ (NTA)] bound to two histidines (dHis) is rigid and yields narrow distance distributions, which can be more easily translated into biomolecular conformations. Here, we use this label on the 71 kDa Yersinia outer protein O (YopO) to decipher whether a previously experimentally observed bimodal distance distribution is due to two conformations of the biomolecule or of the flexible spin labels. Two different PDS experiments, that is, pulsed electron-electron double resonance (PELDOR aka DEER) and relaxation-induced dipolar modulation enhancement (RIDME), yield unimodal distance distribution with the dHis-Cu2+ (NTA) motif; this result suggests that the α-helical backbone of YopO adopts a single conformation in frozen solution. In addition, we show that the Cu2+ (NTA) label preferentially binds to the target double histidine (dHis) sites even in the presence of 22 competing native histidine residues. Our results therefore suggest that the generation of a His-null background is not required for this spin labeling methodology. Together these results highlight the value of the dHis-Cu2+ (NTA) motif in PDS experiments.
Collapse
Affiliation(s)
- Caspar A Heubach
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Zikri Hasanbasri
- Department of Chemistry, Chevron Science Center, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15260, USA
| | - Dinar Abdullin
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Arne Reuter
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| | - Benedict Korzekwa
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
- Leibniz-Center for Diabetes Research, University of Düsseldorf, Auf'm Hennekamp 65, 40225, Düsseldorf, Germany
| | - Sunil Saxena
- Department of Chemistry, Chevron Science Center, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA, 15260, USA
| | - Olav Schiemann
- Clausius-Institute of Physical and Theoretical Chemistry, University of Bonn, Wegelerstr. 12, 53115, Bonn, Germany
| |
Collapse
|
6
|
Stehle J, Fleming JR, Bauer PM, Mayans O, Drescher M. Titin UN2A Acts as a Stable, Non-Polymorphic Scaffold in its Binding to CARP. Chembiochem 2023; 24:e202300408. [PMID: 37503755 DOI: 10.1002/cbic.202300408] [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: 05/31/2023] [Revised: 07/25/2023] [Accepted: 07/27/2023] [Indexed: 07/29/2023]
Abstract
The N2A segment of titin functions as a pivotal hub for signal transduction and interacts with various proteins involved in structural support, chaperone activities, and transcriptional regulation. Notably, the "unique N2A" (UN2A) subdomain has been shown to interact with the stress-regulated cardiac ankyrin repeat protein (CARP), which contributes to the regulation of sarcomeric stiffness. Previously, the UN2A domain's three-dimensional structure was modelled based on its secondary structure content identified by NMR spectroscopy, considering the domain in isolation. In this study, we report experimental long-range distance distributions by electron paramagnetic resonance (EPR) spectroscopy between the three helixes within the UN2A domain linked to the immunoglobulin domain I81 in the presence and absence of CARP. The data confirm the central three-helix bundle fold of UN2A and show that this adopts a compact and stable conformation in absence of CARP. After binding to CARP, no significant conformational change was observed, suggesting that the UN2A domain retains its structure upon binding to CARP thereby, mediating the interaction approximately as a rigid-body.
Collapse
Affiliation(s)
- Juliane Stehle
- Department of Chemistry and Konstanz Research School of Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Jennifer R Fleming
- Department of Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Piera-Maria Bauer
- Department of Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Olga Mayans
- Department of Biology, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Malte Drescher
- Department of Chemistry and Konstanz Research School of Chemical Biology (KoRS-CB), University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| |
Collapse
|
7
|
Bogetti X, Bogetti A, Casto J, Rule G, Chong L, Saxena S. Direct observation of negative cooperativity in a detoxification enzyme at the atomic level by Electron Paramagnetic Resonance spectroscopy and simulation. Protein Sci 2023; 32:e4770. [PMID: 37632831 PMCID: PMC10503414 DOI: 10.1002/pro.4770] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 07/14/2023] [Accepted: 08/23/2023] [Indexed: 08/28/2023]
Abstract
The catalytic activity of human glutathione S-transferase A1-1 (hGSTA1-1), a homodimeric detoxification enzyme, is dependent on the conformational dynamics of a key C-terminal helix α9 in each monomer. However, the structural details of how the two monomers interact upon binding of substrates is not well understood and the structure of the ligand-free state of the hGSTA1-1 homodimer has not been resolved. Here, we used a combination of electron paramagnetic resonance (EPR) distance measurements and weighted ensemble (WE) simulations to characterize the conformational ensemble of the ligand-free state at the atomic level. EPR measurements reveal a broad distance distribution between a pair of Cu(II) labels in the ligand-free state that gradually shifts and narrows as a function of increasing ligand concentration. These shifts suggest changes in the relative positioning of the two α9 helices upon ligand binding. WE simulations generated unbiased pathways for the seconds-timescale transition between alternate states of the enzyme, leading to the generation of atomically detailed structures of the ligand-free state. Notably, the simulations provide direct observations of negative cooperativity between the monomers of hGSTA1-1, which involve the mutually exclusive docking of α9 in each monomer as a lid over the active site. We identify key interactions between residues that lead to this negative cooperativity. Negative cooperativity may be essential for interaction of hGSTA1-1 with a wide variety of toxic substrates and their subsequent neutralization. More broadly, this work demonstrates the power of integrating EPR distances with WE rare-events sampling strategy to gain mechanistic information on protein function at the atomic level.
Collapse
Affiliation(s)
- Xiaowei Bogetti
- Department of ChemistryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Anthony Bogetti
- Department of ChemistryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Joshua Casto
- Department of ChemistryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Gordon Rule
- Department of Biological SciencesCarnegie Mellon UniversityPittsburghPennsylvaniaUSA
| | - Lillian Chong
- Department of ChemistryUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Sunil Saxena
- Department of ChemistryUniversity of PittsburghPittsburghPennsylvaniaUSA
| |
Collapse
|
8
|
Jaiswal M, Zhou M, Guo J, Tran TT, Kundu S, Jaufer AM, Fanucci GE, Guo Z. Different Biophysical Properties of Cell Surface α2,3- and α2,6-Sialoglycans Revealed by Electron Paramagnetic Resonance Spectroscopic Studies. J Phys Chem B 2023; 127:1749-1757. [PMID: 36808907 PMCID: PMC10116567 DOI: 10.1021/acs.jpcb.2c09048] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Sialoglycans on HeLa cells were labeled with a nitroxide spin radical through enzymatic glycoengineering (EGE)-mediated installation of azide-modified sialic acid (Neu5Ac9N3) and then click reaction-based attachment of a nitroxide spin radical. α2,6-Sialyltransferase (ST) Pd2,6ST and α2,3-ST CSTII were used for EGE to install α2,6- and α2,3-linked Neu5Ac9N3, respectively. The spin-labeled cells were analyzed by X-band continuous wave (CW) electron paramagnetic resonance (EPR) spectroscopy to gain insights into the dynamics and organizations of cell surface α2,6- and α2,3-sialoglycans. Simulations of the EPR spectra revealed average fast- and intermediate-motion components for the spin radicals in both sialoglycans. However, α2,6- and α2,3-sialoglycans in HeLa cells possess different distributions of the two components, e.g., a higher average population of the intermediate-motion component for α2,6-sialoglycans (78%) than that for α2,3-sialoglycans (53%). Thus, the average mobility of spin radicals in α2,3-sialoglycans was higher than that in α2,6-sialoglycans. Given the fact that a spin-labeled sialic acid residue attached to the 6-O-position of galactose/N-acetyl-galactosamine would experience less steric hindrance and show more flexibility than that attached to the 3-O-position, these results may reflect the differences in local crowding/packing that restrict the spin-label and sialic acid motion for α2,6-linked sialoglycans. The studies further suggest that Pd2,6ST and CSTII may have different preferences for glycan substrates in the complex environment of the extracellular matrix. The discoveries of this work are biologically important as they are useful for interpreting the different functions of α2,6- and α2,3-sialoglycans and indicate the possibility of using Pd2,6ST and CSTII to target different glycoconjugates on cells.
Collapse
Affiliation(s)
- Mohit Jaiswal
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Mingwei Zhou
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Jiatong Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Trang T Tran
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Sayan Kundu
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Afnan M Jaufer
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Gail E Fanucci
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, Florida 32611, United States
| |
Collapse
|
9
|
Scherer A, Yildirim B, Drescher M. The effect of the zero-field splitting in light-induced pulsed dipolar electron paramagnetic resonance (EPR) spectroscopy. MAGNETIC RESONANCE (GOTTINGEN, GERMANY) 2023; 4:27-46. [PMID: 37904801 PMCID: PMC10583298 DOI: 10.5194/mr-4-27-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 01/13/2023] [Indexed: 11/01/2023]
Abstract
Laser-induced magnetic dipole (LaserIMD) spectroscopy and light-induced double electron-electron resonance (LiDEER) spectroscopy are important techniques in the emerging field of light-induced pulsed dipolar electron paramagnetic resonance (EPR) spectroscopy (light-induced PDS). These techniques use the photoexcitation of a chromophore to the triplet state and measure its dipolar coupling to a neighboring electron spin, which allows the determination of distance restraints. To date, LaserIMD and LiDEER have been analyzed with software tools that were developed for a pair of two S = 1 / 2 spins and that neglected the zero-field splitting (ZFS) of the excited triplet. Here, we explore the limits of this assumption and show that the ZFS can have a significant effect on the shape of the dipolar trace. For a detailed understanding of the effect of the ZFS, a theoretical description for LaserIMD and LiDEER is derived, taking into account the non-secular terms of the ZFS. Simulations based on this model show that the effect of the ZFS is not that pronounced in LiDEER for experimentally relevant conditions. However, the ZFS leads to an additional decay in the dipolar trace in LaserIMD. This decay is not that pronounced in Q-band but can be quite noticeable for lower magnetic field strengths in X-band. Experimentally recorded LiDEER and LaserIMD data confirm these findings. It is shown that ignoring the ZFS in the data analysis of LaserIMD traces can lead to errors in the obtained modulation depths and background decays. In X-band, it is additionally possible that the obtained distance distribution is plagued by long distance artifacts.
Collapse
Affiliation(s)
- Andreas Scherer
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Berk Yildirim
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Malte Drescher
- Department of Chemistry, Konstanz Research School Chemical Biology, University of Konstanz, 78457 Konstanz, Germany
| |
Collapse
|
10
|
Guidelines for the Simulations of Nitroxide X-Band cw EPR Spectra from Site-Directed Spin Labeling Experiments Using S imLabel. Molecules 2023; 28:molecules28031348. [PMID: 36771013 PMCID: PMC9919594 DOI: 10.3390/molecules28031348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/24/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Abstract
Site-directed spin labeling (SDSL) combined with continuous wave electron paramagnetic resonance (cw EPR) spectroscopy is a powerful technique to reveal, at the local level, the dynamics of structural transitions in proteins. Here, we consider SDSL-EPR based on the selective grafting of a nitroxide on the protein under study, followed by X-band cw EPR analysis. To extract valuable quantitative information from SDSL-EPR spectra and thus give a reliable interpretation on biological system dynamics, a numerical simulation of the spectra is required. However, regardless of the numerical tool chosen to perform such simulations, the number of parameters is often too high to provide unambiguous results. In this study, we have chosen SimLabel to perform such simulations. SimLabel is a graphical user interface (GUI) of Matlab, using some functions of Easyspin. An exhaustive review of the parameters used in this GUI has enabled to define the adjustable parameters during the simulation fitting and to fix the others prior to the simulation fitting. Among them, some are set once and for all (gy, gz) and others are determined (Az, gx) thanks to a supplementary X-band spectrum recorded on a frozen solution. Finally, we propose guidelines to perform the simulation of X-band cw-EPR spectra of nitroxide labeled proteins at room temperature, with no need of uncommon higher frequency spectrometry and with the minimal number of variable parameters.
Collapse
|
11
|
Pierro A, Bonucci A, Normanno D, Ansaldi M, Pilet E, Ouari O, Guigliarelli B, Etienne E, Gerbaud G, Magalon A, Belle V, Mileo E. Probing the Structural Dynamics of a Bacterial Chaperone in Its Native Environment by Nitroxide‐Based EPR Spectroscopy. Chemistry 2022; 28:e202202249. [DOI: 10.1002/chem.202202249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Indexed: 11/07/2022]
Affiliation(s)
- Annalisa Pierro
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
- Department of Chemistry University of Konstanz, and Konstanz Research School Chemical Biology 78457 Konstanz Germany
| | - Alessio Bonucci
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| | - Davide Normanno
- Aix Marseille Univ CNRS, Inserm Institut Paoli-Calmettes, CRCM Centre de Recherche en Cancérologie de Marseille 13273 Marseille France
- Univ Montpellier CNRS, IGH Institut de Génétique Humaine 34396 Montpellier France
| | - Mireille Ansaldi
- Aix Marseille Univ CNRS, LCB Laboratoire de Chimie Bacterienne, IMM 13009 Marseille France
| | - Eric Pilet
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| | - Olivier Ouari
- Aix Marseille Univ CNRS, ICR Institut de Chimie Radicalaire 13397 Marseille France
| | - Bruno Guigliarelli
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| | - Emilien Etienne
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| | - Guillaume Gerbaud
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| | - Axel Magalon
- Aix Marseille Univ CNRS, LCB Laboratoire de Chimie Bacterienne, IMM 13009 Marseille France
| | - Valérie Belle
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| | - Elisabetta Mileo
- Aix Marseille Univ CNRS, BIP Bioénérgetique et Ingénierie des Protéines, IMM 13009 Marseille France
| |
Collapse
|
12
|
Rabe P, Walla CC, Goodyear NK, Welsh J, Southwart R, Clifton I, Linyard JDS, Tumber A, Claridge TDW, Myers WK, Schofield CJ. Spectroscopic studies reveal details of substrate-induced conformational changes distant from the active site in isopenicillin N synthase. J Biol Chem 2022; 298:102249. [PMID: 35835215 PMCID: PMC9403350 DOI: 10.1016/j.jbc.2022.102249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 11/06/2022] Open
Abstract
Isopenicillin N synthase (IPNS) catalyzes formation of the β-lactam and thiazolidine rings of isopenicillin N from its linear tripeptide l-δ-(α-aminoadipoyl)-l-cysteinyl-d-valine (ACV) substrate in an iron- and dioxygen (O2)-dependent four-electron oxidation without precedent in current synthetic chemistry. Recent X-ray free-electron laser studies including time-resolved serial femtosecond crystallography show that binding of O2 to the IPNS–Fe(II)–ACV complex induces unexpected conformational changes in α-helices on the surface of IPNS, in particular in α3 and α10. However, how substrate binding leads to conformational changes away from the active site is unknown. Here, using detailed 19F NMR and electron paramagnetic resonance experiments with labeled IPNS variants, we investigated motions in α3 and α10 induced by binding of ferrous iron, ACV, and the O2 analog nitric oxide, using the less mobile α6 for comparison. 19F NMR studies were carried out on singly and doubly labeled α3, α6, and α10 variants at different temperatures. In addition, double electron–electron resonance electron paramagnetic resonance analysis was carried out on doubly spin-labeled variants. The combined spectroscopic and crystallographic results reveal that substantial conformational changes in regions of IPNS including α3 and α10 are induced by binding of ACV and nitric oxide. Since IPNS is a member of the structural superfamily of 2-oxoglutarate-dependent oxygenases and related enzymes, related conformational changes may be of general importance in nonheme oxygenase catalysis.
Collapse
Affiliation(s)
- Patrick Rabe
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom.
| | - Carla C Walla
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Noelle K Goodyear
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Jordan Welsh
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom; Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, UK
| | - Rebecca Southwart
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Ian Clifton
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - James D S Linyard
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Anthony Tumber
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Tim D W Claridge
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - William K Myers
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, UK.
| | - Christopher J Schofield
- Chemistry Research Laboratory, Department of Chemistry and the Ineos Oxford Institute for Antimicrobial Research, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom.
| |
Collapse
|
13
|
Bogetti X, Hasanbasri Z, Hunter HR, Saxena S. An optimal acquisition scheme for Q-band EPR distance measurements using Cu 2+-based protein labels. Phys Chem Chem Phys 2022; 24:14727-14739. [PMID: 35574729 DOI: 10.1039/d2cp01032a] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Recent advances in site-directed Cu2+ labeling of proteins and nucleic acids have added an attractive new methodology to measure the structure-function relationship in biomolecules. Despite the promise, accessing the higher sensitivity of Q-band Double Electron Electron Resonance (DEER) has been challenging for Cu2+ labels designed for proteins. Q-band DEER experiments on this label typically require many measurements at different magnetic fields, since the pulses can excite only a few orientations at a given magnetic field. Herein, we analyze such orientational effects through simulations and show that three DEER measurements, at strategically selected magnetic fields, are generally sufficient to acquire an orientational-averaged DEER time trace for this spin label at Q-band. The modeling results are experimentally verified on Cu2+ labeled human glutathione S-transferase (hGSTA1-1). The DEER distance distribution measured at the Q-band shows good agreement with the distance distribution sampled by molecular dynamics (MD) simulations and X-band experiments. The concordance of MD sampled distances and experimentally measured distances adds growing evidence that MD simulations can accurately predict distances for the Cu2+ labels, which remains a key bottleneck for the commonly used nitroxide label. In all, this minimal collection scheme reduces data collection time by as much as six-fold and is generally applicable to many octahedrally coordinated Cu2+ systems. Furthermore, the concepts presented here may be applied to other metals and pulsed EPR experiments.
Collapse
Affiliation(s)
- Xiaowei Bogetti
- Department of Chemistry, University of Pittsburgh, PA 15260, USA.
| | - Zikri Hasanbasri
- Department of Chemistry, University of Pittsburgh, PA 15260, USA.
| | - Hannah R Hunter
- Department of Chemistry, University of Pittsburgh, PA 15260, USA.
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, PA 15260, USA.
| |
Collapse
|
14
|
Azarkh M, Keller K, Qi M, Godt A, Yulikov M. How accurately defined are the overtone coefficients in Gd(III)-Gd(III) RIDME? JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2022; 339:107217. [PMID: 35453095 DOI: 10.1016/j.jmr.2022.107217] [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: 02/01/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 06/14/2023]
Abstract
Relaxation-induced dipolar modulation enhancement (RIDME) is a pulse EPR technique that is particularly suitable to determine distances between paramagnetic centers with a broad EPR spectrum, e.g. metal-ion-based ones. As far as high-spin systems (S > ½) are concerned, the RIDME experiment provides not only the basic dipolar frequency but also its overtones, which complicates the determination of interspin distances. Here, we present and discuss in a step-by-step fashion an r.m.s.d.-based approach for the calibration of the overtone coefficients for a series of molecular rulers doubly labeled with Gd(III)-PyMTA tags. The constructed 2D total-penalty diagrams help revealing that there is no unique set of overtone coefficients but rather a certain pool, which can be used to extract distance distributions between high-spin paramagnetic centers, as determined from the RIDME experiment. This is of particular importance for comparing RIDME overtone calibration and distance distributions obtained in different labs.
Collapse
Affiliation(s)
- Mykhailo Azarkh
- Department of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany.
| | - Katharina Keller
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Mian Qi
- Faculty of Chemistry and Center for Molecular Materials (CM2), Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Adelheid Godt
- Faculty of Chemistry and Center for Molecular Materials (CM2), Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Maxim Yulikov
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland.
| |
Collapse
|
15
|
Miao Q, Nitsche C, Orton H, Overhand M, Otting G, Ubbink M. Paramagnetic Chemical Probes for Studying Biological Macromolecules. Chem Rev 2022; 122:9571-9642. [PMID: 35084831 PMCID: PMC9136935 DOI: 10.1021/acs.chemrev.1c00708] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Indexed: 12/11/2022]
Abstract
Paramagnetic chemical probes have been used in electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopy for more than four decades. Recent years witnessed a great increase in the variety of probes for the study of biological macromolecules (proteins, nucleic acids, and oligosaccharides). This Review aims to provide a comprehensive overview of the existing paramagnetic chemical probes, including chemical synthetic approaches, functional properties, and selected applications. Recent developments have seen, in particular, a rapid expansion of the range of lanthanoid probes with anisotropic magnetic susceptibilities for the generation of structural restraints based on residual dipolar couplings and pseudocontact shifts in solution and solid state NMR spectroscopy, mostly for protein studies. Also many new isotropic paramagnetic probes, suitable for NMR measurements of paramagnetic relaxation enhancements, as well as EPR spectroscopic studies (in particular double resonance techniques) have been developed and employed to investigate biological macromolecules. Notwithstanding the large number of reported probes, only few have found broad application and further development of probes for dedicated applications is foreseen.
Collapse
Affiliation(s)
- Qing Miao
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
- School
of Chemistry &Chemical Engineering, Shaanxi University of Science & Technology, Xi’an710021, China
| | - Christoph Nitsche
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Henry Orton
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Mark Overhand
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| | - Gottfried Otting
- Research
School of Chemistry, The Australian National
University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
- ARC
Centre of Excellence for Innovations in Peptide & Protein Science,
Research School of Chemistry, Australian
National University, Sullivans Creek Road, Canberra, Australian Capital Territory 2601, Australia
| | - Marcellus Ubbink
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2333 CC, The Netherlands
| |
Collapse
|
16
|
Kugele A, Uzun B, Müller L, Schott-Verdugo S, Gohlke H, Groth G, Drescher M. Mapping the helix arrangement of the reconstituted ETR1 ethylene receptor transmembrane domain by EPR spectroscopy. RSC Adv 2022; 12:7352-7356. [PMID: 35424698 PMCID: PMC8982231 DOI: 10.1039/d2ra00604a] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 02/23/2022] [Indexed: 12/21/2022] Open
Abstract
The plant ethylene receptor ETR1 is a key player in the perception of the phytohormone and subsequent downstream ethylene signal transmission, crucial for processes such as ripening, senescence and abscission. However, to date, there is sparse structural knowledge about the transmembrane sensor domain (TMD) of ETR1 that is responsible for the binding of the plant hormone and initiates the downstream signal transmission. Sequence information and ab initio modelling suggest that the TMD consists of three transmembrane helices. Here, we combined site-directed spin labelling with electron paramagnetic resonance spectroscopy and obtained distance restraints for liposome-reconstituted ETR1_TMD on the orientation and arrangement of the transmembrane helices. We used these data to scrutinize different computational structure predictions of the TMD.
Collapse
Affiliation(s)
- Anandi Kugele
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz Universitätsstraße 10 78457 Konstanz Germany
| | - Buket Uzun
- Institute of Biochemical Plant Physiology, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Lena Müller
- Institute of Biochemical Plant Physiology, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Stephan Schott-Verdugo
- John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH 52425 Jülich Germany
| | - Holger Gohlke
- John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH 52425 Jülich Germany
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf 40225 Düsseldorf Germany
| | - Georg Groth
- Institute of Biochemical Plant Physiology, Heinrich Heine University Düsseldorf Universitätsstraße 1 40225 Düsseldorf Germany
| | - Malte Drescher
- Department of Chemistry and Konstanz Research School Chemical Biology (KoRS-CB), University of Konstanz Universitätsstraße 10 78457 Konstanz Germany
| |
Collapse
|
17
|
Jaiswal M, Tran TT, Guo J, Zhou M, Garcia Diaz J, Fanucci GE, Guo Z. Enzymatic glycoengineering-based spin labelling of cell surface sialoglycans to enable their analysis by electron paramagnetic resonance (EPR) spectroscopy. Analyst 2022; 147:784-788. [PMID: 35171149 PMCID: PMC8885856 DOI: 10.1039/d1an02226a] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/22/2024]
Abstract
A novel method for spin labelling of sialoglycans on the cell surface is described. C9-Azido sialic acid was linked to glycans on live cells via CSTII-catalysed α2,3-sialylation utilizing azido-sialic acid nucleotide as a sialyl donor, which was followed by attachment of a spin label to the azide via click reaction. It enables the study of cell surface sialoglycans by EPR spectroscopy.
Collapse
Affiliation(s)
- Mohit Jaiswal
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| | - Trang T Tran
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| | - Jiatong Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| | - Mingwei Zhou
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| | - Josefina Garcia Diaz
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| | - Gail E Fanucci
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| | - Zhongwu Guo
- Department of Chemistry, University of Florida, 214 Leigh Hall, Gainesville, FL 32611, USA.
| |
Collapse
|
18
|
Biondi B, Syryamina VN, Rocchio G, Barbon A, Formaggio F, Toniolo C, Raap J, Dzuba SA. Is Cys(MTSL) the Best α-Amino Acid Residue to Electron Spin Labeling of Synthetically Accessible Peptide Molecules with Nitroxides? ACS OMEGA 2022; 7:5154-5165. [PMID: 35187331 PMCID: PMC8851612 DOI: 10.1021/acsomega.1c06227] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Electron paramagnetic resonance spectroscopy, particularly its pulse technique double electron-electron resonance (DEER) (also termed PELDOR), is rapidly becoming an extremely useful tool for the experimental determination of side chain-to-side chain distances between free radicals in molecules fundamental for life, such as polypeptides. Among appropriate probes, the most popular are undoubtedly nitroxide electron spin labels. In this context, suitable biosynthetically derived, helical regions of proteins, along with synthetic peptides with amphiphilic properties and antibacterial activities, are the most extensively investigated compounds. A strict requirement for a precise distance measurement has been identified in a minimal dynamic flexibility of the two nitroxide-bearing α-amino acid side chains. To this end, in this study, we have experimentally compared in detail the side-chain mobility properties of the two currently most widely utilized residues, namely, Cys(MTSL) and 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC). In particular, two double-labeled, chemically synthesized 20-mer peptide molecules have been adopted as appropriate templates for our investigation on the determination of the model intramolecular separations. These double-Cys(MTSL) and double-TOAC compounds are both analogues of the almost completely rigid backbone peptide ruler which we have envisaged and 3D structurally analyzed as our original, unlabeled compound. Here, we have clearly found that the TOAC side-chain labels are largely more 3D structurally restricted than the MTSL labels. From this result, we conclude that the TOAC residue offers more precise information than the Cys(MTSL) residue on the side chain-to-side chain distance distribution in synthetically accessible peptide molecules.
Collapse
Affiliation(s)
- Barbara Biondi
- Institute
of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
| | - Victoria N. Syryamina
- Institute
of Chemical Kinetics and Combustion, 630090 Novosibirsk, Russian Federation
| | - Gabriele Rocchio
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Antonio Barbon
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Fernando Formaggio
- Institute
of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Claudio Toniolo
- Institute
of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy
- Department
of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Jan Raap
- Leiden
Institute of Chemistry, Gorlaeus Laboratories,
Leiden University, 2300 RA Leiden, The Netherlands
| | - Sergei A. Dzuba
- Institute
of Chemical Kinetics and Combustion, 630090 Novosibirsk, Russian Federation
- Department
of Physics, Novosibirsk State University, 630090 Novosibirsk, Russian Federation
| |
Collapse
|
19
|
Guo Z, Yan X. Synthesis of Structurally Defined Nitroxide Spin-Labeled Glycolipids as Useful Probes for Electron Paramagnetic Resonance (EPR) Spectroscopy Studies of Cell Surface Glycans. SYNTHESIS-STUTTGART 2022; 54:2856-2864. [DOI: 10.1055/a-1768-2138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractFour glycolipids carrying different glycans and a nitroxide free radical spin at the glycan non-reducing end were designed and synthesized from free glucose and maltooligosaccharides by an efficient and streamlined synthetic strategy. The main features of this synthetic strategy include regioselective functionalization of the free carbohydrates and coupling of the radical spin label with functionalized free glycans as the last synthetic step. These glycolipids are useful probes for the study of cell surface glycans by electron paramagnetic resonance spectroscopy. Moreover, the key synthetic intermediates, free glycolipids carrying a flexible azido group at the glycan non-reducing end, are widely useful platforms for accessing glycolipids with other molecular labels.
Collapse
|
20
|
Tracking protein domain movements by EPR distance determination and multilateration. Methods Enzymol 2022; 666:121-144. [DOI: 10.1016/bs.mie.2022.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
21
|
Hustedt EJ, Stein RA, Mchaourab HS. Protein functional dynamics from the rigorous global analysis of DEER data: Conditions, components, and conformations. J Gen Physiol 2021; 153:212643. [PMID: 34529007 PMCID: PMC8449309 DOI: 10.1085/jgp.201711954] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 08/30/2021] [Indexed: 01/03/2023] Open
Abstract
The potential of spin labeling to reveal the dynamic dimension of macromolecules has been recognized since the dawn of the methodology in the 1960s. However, it was the development of pulsed electron paramagnetic resonance spectroscopy to detect dipolar coupling between spin labels and the availability of turnkey instrumentation in the 21st century that realized the full promise of spin labeling. Double electron-electron resonance (DEER) spectroscopy has seen widespread applications to channels, transporters, and receptors. In these studies, distance distributions between pairs of spin labels obtained under different biochemical conditions report the conformational states of macromolecules, illuminating the key movements underlying biological function. These experimental studies have spurred the development of methods for the rigorous analysis of DEER spectroscopic data along with methods for integrating these distributions into structural models. In this tutorial, we describe a model-based approach to obtaining a minimum set of components of the distance distribution that correspond to functionally relevant protein conformations with a set of fractional amplitudes that define the equilibrium between these conformations. Importantly, we review and elaborate on the error analysis reflecting the uncertainty in the various parameters, a critical step in rigorous structural interpretation of the spectroscopic data.
Collapse
Affiliation(s)
- Eric J Hustedt
- Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Richard A Stein
- Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| | - Hassane S Mchaourab
- Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN
| |
Collapse
|
22
|
Khoroshunova YV, Morozov DA, Taratayko AI, Dobrynin SA, Eltsov IV, Rybalova TV, Sotnikova YS, Polovyanenko DN, Asanbaeva NB, Kirilyuk IA. The Reactions of 6-(Hydroxymethyl)-2,2-dimethyl-1-azaspiro[4.4]nonanes with Methanesulfonyl Chloride or PPh 3-CBr 4. Molecules 2021; 26:molecules26196000. [PMID: 34641544 PMCID: PMC8512565 DOI: 10.3390/molecules26196000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 09/24/2021] [Accepted: 09/29/2021] [Indexed: 11/29/2022] Open
Abstract
Activation of a hydroxyl group towards nucleophilic substitution via reaction with methanesulfonyl chloride or PPh3-CBr4 system is a commonly used pathway to various functional derivatives. The reactions of (5R(S),6R(S))-1-X-6-(hydroxymethyl)-2,2-dimethyl- 1-azaspiro[4.4]nonanes 1a–d (X = O·; H; OBn, OBz) with MsCl/NR3 or PPh3-CBr4 were studied. Depending on substituent X, the reaction afforded hexahydro-1H,6H-cyclopenta[c]pyrrolo[1,2-b]isoxazole (2) (for X = O), a mixture of 2 and octahydrocyclopenta[c]azepines (4–6) (for X = OBn, OBz), or perhydro-cyclopenta[2,3]azeto[1,2-a]pyrrol (3) (for X = H) derivatives. Alkylation of the latter with MeI with subsequent Hofmann elimination afforded 2,3,3-trimethyl-1,2,3,4,5,7,8,8a-octahydrocyclopenta[c]azepine with 56% yield.
Collapse
Affiliation(s)
- Yulia V. Khoroshunova
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova Str. 1, 630090 Novosibirsk, Russia;
- Correspondence:
| | - Denis A. Morozov
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
| | - Andrey I. Taratayko
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova Str. 1, 630090 Novosibirsk, Russia;
| | - Sergey A. Dobrynin
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
| | - Ilia V. Eltsov
- Department of Natural Sciences, Novosibirsk State University, Pirogova Str. 1, 630090 Novosibirsk, Russia;
| | - Tatyana V. Rybalova
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
| | - Yulia S. Sotnikova
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
| | - Dmitriy N. Polovyanenko
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
| | - Nargiz B. Asanbaeva
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
- Department of Natural Sciences, Novosibirsk State University, Pirogova Str. 1, 630090 Novosibirsk, Russia;
| | - Igor A. Kirilyuk
- N.N. Vorozhtsov Institute of Organic Chemistry SB RAS, Academician Lavrentiev Ave. 9, 630090 Novosibirsk, Russia; (D.A.M.); (A.I.T.); (S.A.D.); (T.V.R.); (Y.S.S.); (D.N.P.); (N.B.A.); (I.A.K.)
| |
Collapse
|
23
|
A Simple Method of Synthesis of 3-Carboxy-2,2,5,5-Tetraethylpyrrolidine-1-oxyl and Preparation of Reduction-Resistant Spin Labels and Probes of Pyrrolidine Series. Molecules 2021; 26:molecules26195761. [PMID: 34641310 PMCID: PMC8510269 DOI: 10.3390/molecules26195761] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 09/17/2021] [Accepted: 09/19/2021] [Indexed: 01/31/2023] Open
Abstract
Stable free radicals are widely used as molecular probes and labels in various biophysical and biomedical research applications of magnetic resonance spectroscopy and imaging. Among these radicals, sterically shielded nitroxides of pyrrolidine series demonstrate the highest stability in biological systems. Here, we suggest new convenient procedure for preparation of 3-carboxy-2,2,5,5-tetraethylpyrrolidine-1-oxyl, a reduction-resistant analog of widely used carboxy-Proxyl, from cheap commercially available reagents with the yield exceeding the most optimistic literature data. Several new spin labels and probes of 2,2,5,5-tetraethylpyrrolidine-1-oxyl series were prepared and reduction of these radicals in ascorbate solutions, mice blood and tissue homogenates was studied.
Collapse
|
24
|
Yeliseev AA, Zoretich K, Hooper L, Teague W, Zoubak L, Hines KG, Gawrisch K. Site-selective labeling and electron paramagnetic resonance studies of human cannabinoid receptor CB 2. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2021; 1863:183621. [PMID: 33865808 PMCID: PMC8154700 DOI: 10.1016/j.bbamem.2021.183621] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 03/19/2021] [Accepted: 03/26/2021] [Indexed: 11/19/2022]
Abstract
Integral membrane G protein-coupled receptors (GPCR) regulate multiple physiological processes by transmitting signals from extracellular milieu to intracellular proteins and are major targets of pharmaceutical drug development. Since GPCR are inherently flexible proteins, their conformational dynamics can be studied by spectroscopic techniques such as electron paramagnetic resonance (EPR) which requires selective chemical labeling of the protein. Here, we developed protocols for selective chemical labeling of the recombinant human cannabinoid receptor CB2 by judiciously replacing naturally occurring reactive cysteine residues and introducing a new single cysteine residue in selected positions. The majority of the 47 newly generated single cysteine constructs expressed well in E. coli cells, and more than half of them retained high functional activity. The reactivity of newly introduced cysteine residues was assessed by incorporating nitroxide spin label and EPR measurement. The conformational transition of the receptor between the inactive and activated form were studied by EPR of selectively labeled constructs in the presence of either a full agonist CP-55,940 or an inverse agonist SR-144,528. We observed evidence for higher mobility of labels in the center of internal loop 3 and a structural change between agonist vs. inverse agonist-bound CB2 in the extracellular tip of transmembrane helix 6. Our results demonstrate the utility of EPR for studies of conformational dynamics of CB2.
Collapse
Affiliation(s)
- Alexei A Yeliseev
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Kaeli Zoretich
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Levi Hooper
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Walter Teague
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lioudmila Zoubak
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kirk G Hines
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA
| | - Klaus Gawrisch
- National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
25
|
Hasanbasri Z, Singewald K, Gluth TD, Driesschaert B, Saxena S. Cleavage-Resistant Protein Labeling With Hydrophilic Trityl Enables Distance Measurements In-Cell. J Phys Chem B 2021; 125:5265-5274. [PMID: 33983738 DOI: 10.1021/acs.jpcb.1c02371] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sensitive in-cell distance measurements in proteins using pulsed-electron spin resonance (ESR) require reduction-resistant and cleavage-resistant spin labels. Among the reduction-resistant moieties, the hydrophilic trityl core known as OX063 is promising due to its long phase-memory relaxation time (Tm). This property leads to a sufficiently intense ESR signal for reliable distance measurements. Furthermore, the Tm of OX063 remains sufficiently long at higher temperatures, opening the possibility for measurements at temperatures above 50 K. In this work, we synthesized deuterated OX063 with a maleimide linker (mOX063-d24). We show that the combination of the hydrophilicity of the label and the maleimide linker enables high protein labeling that is cleavage-resistant in-cells. Distance measurements performed at 150 K using this label are more sensitive than the measurements at 80 K. The sensitivity gain is due to the significantly short longitudinal relaxation time (T1) at higher temperatures, which enables more data collection per unit of time. In addition to in vitro experiments, we perform distance measurements in Xenopus laevis oocytes. Interestingly, the Tm of mOX063-d24 is sufficiently long even in the crowded environment of the cell, leading to signals of appreciable intensity. Overall, mOX063-d24 provides highly sensitive distance measurements both in vitro and in-cells.
Collapse
Affiliation(s)
- Zikri Hasanbasri
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Kevin Singewald
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Teresa D Gluth
- Department of Pharmaceutical Sciences, School of Pharmacy & In Vivo Multifunctional Magnetic Resonance (IMMR) Center, Health Sciences Center, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Benoit Driesschaert
- Department of Pharmaceutical Sciences, School of Pharmacy & In Vivo Multifunctional Magnetic Resonance (IMMR) Center, Health Sciences Center, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| |
Collapse
|
26
|
Probing Structural Dynamics of Membrane Proteins Using Electron Paramagnetic Resonance Spectroscopic Techniques. BIOPHYSICA 2021. [DOI: 10.3390/biophysica1020009] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Membrane proteins are essential for the survival of living organisms. They are involved in important biological functions including transportation of ions and molecules across the cell membrane and triggering the signaling pathways. They are targets of more than half of the modern medical drugs. Despite their biological significance, information about the structural dynamics of membrane proteins is lagging when compared to that of globular proteins. The major challenges with these systems are low expression yields and lack of appropriate solubilizing medium required for biophysical techniques. Electron paramagnetic resonance (EPR) spectroscopy coupled with site directed spin labeling (SDSL) is a rapidly growing powerful biophysical technique that can be used to obtain pertinent structural and dynamic information on membrane proteins. In this brief review, we will focus on the overview of the widely used EPR approaches and their emerging applications to answer structural and conformational dynamics related questions on important membrane protein systems.
Collapse
|
27
|
Giannoulis A, Ben-Ishay Y, Goldfarb D. Characteristics of Gd(III) spin labels for the study of protein conformations. Methods Enzymol 2021; 651:235-290. [PMID: 33888206 DOI: 10.1016/bs.mie.2021.01.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Gd(III) complexes are currently established as spin labels for structural studies of biomolecules using pulse dipolar electron paramagnetic resonance (PD-EPR) techniques. This has been achieved by the availability of medium- and high-field spectrometers, understanding the spin physics underlying the spectroscopic properties of high spin Gd(III) (S=7/2) pairs and their dipolar interaction, the design of well-defined model compounds and optimization of measurement techniques. In addition, a variety of Gd(III) chelates and labeling schemes have allowed a broad scope of applications. In this review, we provide a brief background of the spectroscopic properties of Gd(III) pertinent for effective PD-EPR measurements and focus on the various labels available to date. We report on their use in PD-EPR applications and highlight their pros and cons for particular applications. We also devote a section to recent in-cell structural studies of proteins using Gd(III), which is an exciting new direction for Gd(III) spin labeling.
Collapse
Affiliation(s)
- Angeliki Giannoulis
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Yasmin Ben-Ishay
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Daniella Goldfarb
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
28
|
Emerging applications of site-directed spin labeling electron paramagnetic resonance (SDSL-EPR) to study food protein structure, dynamics, and interaction. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.01.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
|
29
|
Polienko YF, Kuprikova NM, Parkhomenko DA, Gatilov YV, Chernyak EI, Kirilyuk IA. Synthesis of 2,5-bis(spirocyclohexane)-substituted nitroxides: New spin labeling agents. Tetrahedron 2021. [DOI: 10.1016/j.tet.2020.131915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
30
|
Le Nguyen Ngoc L, Pandey RB, Sompornpisut P. Dynamics and Environmental Characteristics of Spin Labels in a KvAP Voltage Sensor by Molecular Dynamics Simulations. J Phys Chem B 2021; 125:748-756. [PMID: 33459015 DOI: 10.1021/acs.jpcb.0c08993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The nitroxide spin label is the most widely used probe for electron paramagnetic resonance (EPR) spectroscopy studies of the structure and function of biomolecules. However, the role of surrounding environments in determining the dynamics of nitroxide spin labels in biological complex systems remains to be clarified. This study aims to characterize the dynamics and environmental structure of spin labels in the voltage-sensing domain (VSD) of a KvAP potassium channel by means of molecular dynamics (MD) studies. MD simulations for unlabeled and 132 spin-labeled KvAP-VSD models (spin labels introduced at positions 20-151) were carried out in a phospholipid bilayer to evaluate conformational dynamics of nitroxide spin-label side chains in the VSD. Structural flexibility, conformational freedom, and orientation of the spin-label side chains were investigated in relation to their dynamics in different microenvironments. The analysis of MD data showed that the attached spin-label probe did not severely perturb the protein dynamics. The conformational freedoms of the nitroxide side chain vary with the physical structure of the surrounding environments. The two terminal dihedral angles of the nitroxide side chain tend to cluster and adopt several preferred rotameric states. From the nearest-neighbor analysis, the spin label can be exposed to either a homogeneous or heterogeneous environment with various exposure scenarios. The dynamical movement of KvAP-VSD is high at a water-exposed site, moderate in the membrane, and low in the protein core. Understanding the structure and dynamics behaviors of spin labels helps to manage the experimental uncertainty and avoid misleading interpretation in relation to the protein structure.
Collapse
Affiliation(s)
- Lan Le Nguyen Ngoc
- Center of Excellence in Computational Chemistry, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| | - Ras B Pandey
- School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Pornthep Sompornpisut
- Center of Excellence in Computational Chemistry, Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand
| |
Collapse
|
31
|
Welegedara AP, Maleckis A, Bandara R, Mahawaththa MC, Dilhani Herath I, Jiun Tan Y, Giannoulis A, Goldfarb D, Otting G, Huber T. Cell-Free Synthesis of Selenoproteins in High Yield and Purity for Selective Protein Tagging. Chembiochem 2021; 22:1480-1486. [PMID: 33319405 DOI: 10.1002/cbic.202000785] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 12/10/2020] [Indexed: 01/10/2023]
Abstract
The selenol group of selenocysteine is much more nucleophilic than the thiol group of cysteine. Selenocysteine residues in proteins thus offer reactive points for rapid post-translational modification. Herein, we show that selenoproteins can be expressed in high yield and purity by cell-free protein synthesis by global substitution of cysteine by selenocysteine. Complete alkylation of solvent-exposed selenocysteine residues was achieved in 10 minutes with 4-chloromethylene dipicolinic acid (4Cl-MDPA) under conditions that left cysteine residues unchanged even after overnight incubation. GdIII -GdIII distances measured by double electron-electron resonance (DEER) experiments of maltose binding protein (MBP) containing two selenocysteine residues tagged with 4Cl-MDPA-GdIII were indistinguishable from GdIII -GdIII distances measured of MBP containing cysteine reacted with 4Br-MDPA tags.
Collapse
Affiliation(s)
- Adarshi P Welegedara
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia.,Department of Chemistry, University of Peradeniya, Peradeniya, 20400, Sri Lanka
| | - Ansis Maleckis
- Latvian Institute of Organic Synthesis, 1006, Riga, Latvia
| | - Ruchira Bandara
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia
| | - Mithun C Mahawaththa
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia
| | - Iresha Dilhani Herath
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia
| | - Yi Jiun Tan
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia
| | - Angeliki Giannoulis
- Department of Chemical and Biological Physics Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Daniella Goldfarb
- Department of Chemical and Biological Physics Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Gottfried Otting
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia
| | - Thomas Huber
- Australian National University, Research School of Chemistry, Canberra, ACT 2601, Australia
| |
Collapse
|
32
|
Golysheva EA, Boyle AL, Biondi B, Ruzza P, Kros A, Raap J, Toniolo C, Formaggio F, Dzuba SA. Probing the E/K Peptide Coiled-Coil Assembly by Double Electron-Electron Resonance and Circular Dichroism. Biochemistry 2020; 60:19-30. [PMID: 33320519 DOI: 10.1021/acs.biochem.0c00773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Double electron-electron resonance (DEER, also known as PELDOR) and circular dichroism (CD) spectroscopies were explored for the purpose of studying the specificity of the conformation of peptides induced by their assembly into a self-recognizing system. The E and K peptides are known to form a coiled-coil heterodimer. Two paramagnetic TOAC α-amino acid residues were incorporated into each of the peptides (denoted as K** and E**), and a three-dimensional structural investigation in the presence or absence of their unlabeled counterparts E and K was performed. The TOAC spin-labels, replacing two Ala residues in each compound, are covalently and quasi-rigidly connected to the peptide backbone. They are known not to disturb the native structure, so that any conformational change can easily be monitored and assigned. DEER spectroscopy enables the measurement of the intramolecular electron spin-spin distance distribution between the two TOAC labels, within a length range of 1.5-8 nm. This method allows the individual conformational changes for the K**, K**/E, E**, and E**/K molecules to be investigated in glassy frozen solutions. Our data reveal that the conformations of the E** and K** peptides are strongly influenced by the presence of their counterparts. The results are discussed with those from CD spectroscopy and with reference to the already reported nuclear magnetic resonance data. We conclude that the combined DEER/TOAC approach allows us to obtain accurate and reliable information about the conformation of the peptides before and after their assembly into coiled-coil heterodimers. Applications of this induced fit method to other two-component, but more complex, systems, like a receptor and antagonists, a receptor and a hormone, and an enzyme and a ligand, are discussed.
Collapse
Affiliation(s)
- Elena A Golysheva
- Novosibirsk State University, Novosibirsk 630090, Russian Federation.,V. V. Voevodsky Institute of Chemical Kinetics and Combustion, Novosibirsk 630090, Russian Federation
| | - Aimee L Boyle
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden, The Netherlands
| | - Barbara Biondi
- Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.,Department of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Paolo Ruzza
- Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.,Department of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Alexander Kros
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden, The Netherlands
| | - Jan Raap
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden, The Netherlands
| | - Claudio Toniolo
- Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.,Department of Chemical Sciences, University of Padova, 35131 Padova, Italy.,Department of Chemistry, University of Padova, 35131 Padova, Italy
| | - Fernando Formaggio
- Institute of Biomolecular Chemistry, Padova Unit, CNR, 35131 Padova, Italy.,Department of Chemical Sciences, University of Padova, 35131 Padova, Italy
| | - Sergei A Dzuba
- Novosibirsk State University, Novosibirsk 630090, Russian Federation.,V. V. Voevodsky Institute of Chemical Kinetics and Combustion, Novosibirsk 630090, Russian Federation
| |
Collapse
|
33
|
Jaiswal M, Tran TT, Li Q, Yan X, Zhou M, Kundu K, Fanucci GE, Guo Z. A metabolically engineered spin-labeling approach for studying glycans on cells. Chem Sci 2020; 11:12522-12532. [PMID: 34094453 PMCID: PMC8162880 DOI: 10.1039/d0sc03874a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 10/14/2020] [Indexed: 11/30/2022] Open
Abstract
Metabolic glycan engineering (MGE) coupled with nitroxide spin-labeling (SL) was utilized to investigate the heterogeneous environment of cell surface glycans in select cancer and normal cells. This approach exploited the incorporation of azides into cell surface glycans followed by a click reaction with a new nitroxide spin label. Both sialic acid and N-acetylglucosamine (GlcNAc) were targeted for spin labelling. Although each of these moieties experiences a diverse and heterogeneous glycan environment, their EPR spectra and hence mobility are both characterized as a linear combination of two distinct spectra where one component reflects a highly mobile or uncrowded micro-environment with the second component reflecting more restricted motion, reflective of increased crowding and packing within the glycocalyx. What differs among the spectra of the targeted glycans is the relative percentage of each component, with sialic acid moieties experiencing on average an ∼80% less crowded environment, where conversely GlcNAc/GalNAz labeled sites reported on average a ∼50% more crowded environment. These distinct environments are consistent with the organization of sugar moieties within cellular glycans where some residues occur close to the cell membrane/protein backbone (i.e. more restricted) and others are more terminal in the glycan (i.e. more mobile). Strikingly, different cell lines displayed varied relative populations of these two components, suggesting distinctive glycan packing, organization, and composition of different cells. This work demonstrates the capability of SDSL EPR to be a broadly useful tool for studying glycans on cells, and interpretation of the results provides insights for distinguishing the differences and changes in the local organization and heterogeneity of the cellular glycocalyx.
Collapse
Affiliation(s)
- Mohit Jaiswal
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| | - Trang T Tran
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| | - Qingjiang Li
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| | - Xin Yan
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| | - Mingwei Zhou
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| | - Krishnendu Kundu
- National High Magnetic Field Laboratory, Florida State University Tallahassee Florida 32310 USA
| | - Gail E Fanucci
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| | - Zhongwu Guo
- Department of Chemistry, University of Florida 214 Leigh Hall Gainesville FL 32611 USA
| |
Collapse
|
34
|
Votkina DE, Petunin PV, Trusova ME, Postnikov PS, Audran G, Marque SRA. Kinetic investigation of thermal and photoinduced homolysis of alkylated verdazyls. Phys Chem Chem Phys 2020; 22:21881-21887. [PMID: 32968753 DOI: 10.1039/d0cp03151h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The on-demand generation of stable organic radicals from the precursors can be considered as an essential challenge for the plethora of applications in various fields of science. In this contribution, we prepared a range of N-(methyl)benzyl derivatives of 6-oxoverdazyl via atom transfer radical addition from moderate to high yields and studied their thermal- and photo-initiated homolysis. The kinetics of homolysis was measured, and the dissociating rate constant kd, activation energy Ea and frequency factor A were estimated. Variation of the substituent at the C3-position of the verdazyl ring was successfully applied for fine-tuning the homolysis rate: the value of kd was higher for alkylverdazyls with electron-withdrawing groups, e.g., the para nitro group afforded a 6-fold increase in kd. In contrast to thermal homolysis, the rate of photoinduced decomposition depends on both the extinction coefficient and the value of activation energy. Thus, nitro-containing alkylated verdazyls show the highest homolysis rate in both types of initiations. The achieved results afford a novel opportunity in the controlled generation of verdazyls and further application of these compounds in medicine and chemical industry.
Collapse
Affiliation(s)
- Darya E Votkina
- Research School of Chemistry & Applied Biomedical Sciences, Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk, 634050, Russia.
| | | | | | | | | | | |
Collapse
|
35
|
Liu J, Cheng R, Van Eps N, Wang N, Morizumi T, Ou WL, Klauser PC, Rozovsky S, Ernst OP, Wang L. Genetically Encoded Quinone Methides Enabling Rapid, Site-Specific, and Photocontrolled Protein Modification with Amine Reagents. J Am Chem Soc 2020; 142:17057-17068. [PMID: 32915556 DOI: 10.1021/jacs.0c06820] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Site-specific modification of proteins with functional molecules provides powerful tools for researching and engineering proteins. Here we report a new chemical conjugation method which photocages highly reactive but chemically selective moieties, enabling the use of protein-inert amines for selective protein modification. New amino acids FnbY and FmnbY, bearing photocaged quinone methides (QMs), were genetically incorporated into proteins. Upon light activation, they generated highly reactive QM, which rapidly reacted with amine derivatives. This method features a rare combination of desired properties including fast kinetics, small and stable linkage, compatibility with low temperature, photocontrollability, and widely available reagents. Moreover, labeling via FnbY occurs on the β-carbon, affording the shortest linkage to protein backbone which is essential for advanced studies involving orientation and distance. We installed various functionalities onto proteins and attached a spin label as close as possible to the protein backbone, achieving high resolution in double electron-electron paramagnetic resonance distance measurements.
Collapse
Affiliation(s)
- Jun Liu
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California San Francisco, 555 Mission Bay Blvd. South, San Francisco, California 94158, United States
| | - Rujin Cheng
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Ned Van Eps
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Nanxi Wang
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California San Francisco, 555 Mission Bay Blvd. South, San Francisco, California 94158, United States
| | - Takefumi Morizumi
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Wei-Lin Ou
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Paul C Klauser
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California San Francisco, 555 Mission Bay Blvd. South, San Francisco, California 94158, United States
| | - Sharon Rozovsky
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Oliver P Ernst
- Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Lei Wang
- Department of Pharmaceutical Chemistry and the Cardiovascular Research Institute, University of California San Francisco, 555 Mission Bay Blvd. South, San Francisco, California 94158, United States
| |
Collapse
|
36
|
Pierro A, Etienne E, Gerbaud G, Guigliarelli B, Ciurli S, Belle V, Zambelli B, Mileo E. Nickel and GTP Modulate Helicobacter pylori UreG Structural Flexibility. Biomolecules 2020; 10:E1062. [PMID: 32708696 PMCID: PMC7408563 DOI: 10.3390/biom10071062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/25/2020] [Accepted: 07/10/2020] [Indexed: 12/14/2022] Open
Abstract
UreG is a P-loop GTP hydrolase involved in the maturation of nickel-containing urease, an essential enzyme found in plants, fungi, bacteria, and archaea. This protein couples the hydrolysis of GTP to the delivery of Ni(II) into the active site of apo-urease, interacting with other urease chaperones in a multi-protein complex necessary for enzyme activation. Whereas the conformation of Helicobacter pylori (Hp) UreG was solved by crystallography when it is in complex with two other chaperones, in solution the protein was found in a disordered and flexible form, defining it as an intrinsically disordered enzyme and indicating that the well-folded structure found in the crystal state does not fully reflect the behavior of the protein in solution. Here, isothermal titration calorimetry and site-directed spin labeling coupled to electron paramagnetic spectroscopy were successfully combined to investigate HpUreG structural dynamics in solution and the effect of Ni(II) and GTP on protein mobility. The results demonstrate that, although the protein maintains a flexible behavior in the metal and nucleotide bound forms, concomitant addition of Ni(II) and GTP exerts a structural change through the crosstalk of different protein regions.
Collapse
Affiliation(s)
- Annalisa Pierro
- Aix Marseille Univ, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, IMM, Marseille, France; (A.P.); (E.E.); (G.G.); (B.G.); (V.B.)
| | - Emilien Etienne
- Aix Marseille Univ, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, IMM, Marseille, France; (A.P.); (E.E.); (G.G.); (B.G.); (V.B.)
| | - Guillaume Gerbaud
- Aix Marseille Univ, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, IMM, Marseille, France; (A.P.); (E.E.); (G.G.); (B.G.); (V.B.)
| | - Bruno Guigliarelli
- Aix Marseille Univ, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, IMM, Marseille, France; (A.P.); (E.E.); (G.G.); (B.G.); (V.B.)
| | - Stefano Ciurli
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, 40127 Bologna, Italy;
| | - Valérie Belle
- Aix Marseille Univ, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, IMM, Marseille, France; (A.P.); (E.E.); (G.G.); (B.G.); (V.B.)
| | - Barbara Zambelli
- Laboratory of Bioinorganic Chemistry, Department of Pharmacy and Biotechnology, University of Bologna, 40127 Bologna, Italy;
| | - Elisabetta Mileo
- Aix Marseille Univ, CNRS, BIP, Bioénergétique et Ingénierie des Protéines, IMM, Marseille, France; (A.P.); (E.E.); (G.G.); (B.G.); (V.B.)
| |
Collapse
|
37
|
Softley CA, Bostock MJ, Popowicz GM, Sattler M. Paramagnetic NMR in drug discovery. JOURNAL OF BIOMOLECULAR NMR 2020; 74:287-309. [PMID: 32524233 PMCID: PMC7311382 DOI: 10.1007/s10858-020-00322-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 05/26/2020] [Indexed: 05/05/2023]
Abstract
The presence of an unpaired electron in paramagnetic molecules generates significant effects in NMR spectra, which can be exploited to provide restraints complementary to those used in standard structure-calculation protocols. NMR already occupies a central position in drug discovery for its use in fragment screening, structural biology and validation of ligand-target interactions. Paramagnetic restraints provide unique opportunities, for example, for more sensitive screening to identify weaker-binding fragments. A key application of paramagnetic NMR in drug discovery, however, is to provide new structural restraints in cases where crystallography proves intractable. This is particularly important at early stages in drug-discovery programs where crystal structures of weakly-binding fragments are difficult to obtain and crystallization artefacts are probable, but structural information about ligand poses is crucial to guide medicinal chemistry. Numerous applications show the value of paramagnetic restraints to filter computational docking poses and to generate interaction models. Paramagnetic relaxation enhancements (PREs) generate a distance-dependent effect, while pseudo-contact shift (PCS) restraints provide both distance and angular information. Here, we review strategies for introducing paramagnetic centers and discuss examples that illustrate the utility of paramagnetic restraints in drug discovery. Combined with standard approaches, such as chemical shift perturbation and NOE-derived distance information, paramagnetic NMR promises a valuable source of information for many challenging drug-discovery programs.
Collapse
Affiliation(s)
- Charlotte A Softley
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Mark J Bostock
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Grzegorz M Popowicz
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Michael Sattler
- Biomolecular NMR and Center for Integrated Protein Science Munich at Department Chemie, Technical University of Munich, Lichtenbergstraße 4, 85747, Garching, Germany.
- Institute of Structural Biology, Helmholtz Zentrum München, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany.
| |
Collapse
|
38
|
Uddin MA, Yu H, Wang L, Naveed K, Haq F, Amin BU, Mehmood S, Nazir A, Xing Y, Shen D. Recent progress in
EPR
study of spin labeled polymers and spin probed polymer systems. JOURNAL OF POLYMER SCIENCE 2020. [DOI: 10.1002/pol.20200039] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Md Alim Uddin
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Haojie Yu
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Li Wang
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Kaleem‐ur‐Rahman Naveed
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Fazal Haq
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Bilal Ul Amin
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Sahid Mehmood
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Ahsan Nazir
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Yusheng Xing
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| | - Di Shen
- State Key Laboratory of Chemical Engineering, College of Chemical and Biological EngineeringZhejiang University Hangzhou Zhejiang China
| |
Collapse
|
39
|
Fleck N, Heubach CA, Hett T, Haege FR, Bawol PP, Baltruschat H, Schiemann O. SLIM: A Short-Linked, Highly Redox-Stable Trityl Label for High-Sensitivity In-Cell EPR Distance Measurements. Angew Chem Int Ed Engl 2020; 59:9767-9772. [PMID: 32329172 PMCID: PMC7318235 DOI: 10.1002/anie.202004452] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Indexed: 12/15/2022]
Abstract
The understanding of biomolecular function is coupled to knowledge about the structure and dynamics of these biomolecules, preferably acquired under native conditions. In this regard, pulsed dipolar EPR spectroscopy (PDS) in conjunction with site-directed spin labeling (SDSL) is an important method in the toolbox of biophysical chemistry. However, the currently available spin labels have diverse deficiencies for in-cell applications, for example, low radical stability or long bioconjugation linkers. In this work, a synthesis strategy is introduced for the derivatization of trityl radicals with a maleimide-functionalized methylene group. The resulting trityl spin label, called SLIM, yields narrow distance distributions, enables highly sensitive distance measurements down to concentrations of 90 nm, and shows high stability against reduction. Using this label, the guanine-nucleotide dissociation inhibitor (GDI) domain of Yersinia outer protein O (YopO) is shown to change its conformation within eukaryotic cells.
Collapse
Affiliation(s)
- Nico Fleck
- Institute of Physical and Theoretical ChemistryUniversity of BonnWegelerstr. 1253115BonnGermany
| | - Caspar A. Heubach
- Institute of Physical and Theoretical ChemistryUniversity of BonnWegelerstr. 1253115BonnGermany
| | - Tobias Hett
- Institute of Physical and Theoretical ChemistryUniversity of BonnWegelerstr. 1253115BonnGermany
| | - Florian R. Haege
- Institute of Physical and Theoretical ChemistryUniversity of BonnWegelerstr. 1253115BonnGermany
| | - Pawel P. Bawol
- Institute of Physical and Theoretical ChemistryUniversity of BonnRömerstr. 16453117BonnGermany
| | - Helmut Baltruschat
- Institute of Physical and Theoretical ChemistryUniversity of BonnRömerstr. 16453117BonnGermany
| | - Olav Schiemann
- Institute of Physical and Theoretical ChemistryUniversity of BonnWegelerstr. 1253115BonnGermany
| |
Collapse
|
40
|
Sahu ID, Lorigan GA. Electron Paramagnetic Resonance as a Tool for Studying Membrane Proteins. Biomolecules 2020; 10:E763. [PMID: 32414134 PMCID: PMC7278021 DOI: 10.3390/biom10050763] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/24/2020] [Accepted: 04/24/2020] [Indexed: 12/13/2022] Open
Abstract
Membrane proteins possess a variety of functions essential to the survival of organisms. However, due to their inherent hydrophobic nature, it is extremely difficult to probe the structure and dynamic properties of membrane proteins using traditional biophysical techniques, particularly in their native environments. Electron paramagnetic resonance (EPR) spectroscopy in combination with site-directed spin labeling (SDSL) is a very powerful and rapidly growing biophysical technique to study pertinent structural and dynamic properties of membrane proteins with no size restrictions. In this review, we will briefly discuss the most commonly used EPR techniques and their recent applications for answering structure and conformational dynamics related questions of important membrane protein systems.
Collapse
Affiliation(s)
- Indra D. Sahu
- Natural Science Division, Campbellsville University, Campbellsville, KY 42718, USA
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| | - Gary A. Lorigan
- Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA
| |
Collapse
|
41
|
EPR of site-directed spin-labeled proteins: A powerful tool to study structural flexibility. Arch Biochem Biophys 2020; 684:108323. [DOI: 10.1016/j.abb.2020.108323] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 02/17/2020] [Accepted: 02/24/2020] [Indexed: 12/20/2022]
|
42
|
Fleck N, Heubach CA, Hett T, Haege FR, Bawol PP, Baltruschat H, Schiemann O. SLIM: A Short‐Linked, Highly Redox‐Stable Trityl Label for High‐Sensitivity In‐Cell EPR Distance Measurements. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202004452] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Nico Fleck
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Caspar A. Heubach
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Tobias Hett
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Florian R. Haege
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| | - Pawel P. Bawol
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Römerstr. 164 53117 Bonn Germany
| | - Helmut Baltruschat
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Römerstr. 164 53117 Bonn Germany
| | - Olav Schiemann
- Institute of Physical and Theoretical ChemistryUniversity of Bonn Wegelerstr. 12 53115 Bonn Germany
| |
Collapse
|
43
|
Braun TS, Widder P, Osswald U, Groß L, Williams L, Schmidt M, Helmle I, Summerer D, Drescher M. Isoindoline-Based Nitroxides as Bioresistant Spin Labels for Protein Labeling through Cysteines and Alkyne-Bearing Noncanonical Amino Acids. Chembiochem 2020; 21:958-962. [PMID: 31657498 PMCID: PMC7187341 DOI: 10.1002/cbic.201900537] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/18/2019] [Indexed: 12/15/2022]
Abstract
Electron paramagnetic resonance (EPR) spectroscopy in combination with site-directed spin labeling (SDSL) is a powerful tool in protein structural research. Nitroxides are highly suitable spin labeling reagents, but suffer from limited stability, particularly in the cellular environment. Herein we present the synthesis of a maleimide- and an azide-modified tetraethyl-shielded isoindoline-based nitroxide (M- and Az-TEIO) for labeling of cysteines or the noncanonical amino acid para-ethynyl-l-phenylalanine (pENF). We demonstrate the high stability of TEIO site-specifically attached to the protein thioredoxin (TRX) against reduction in prokaryotic and eukaryotic environments, and conduct double electron-electron resonance (DEER) measurements. We further generate a rotamer library for the new residue pENF-Az-TEIO that affords a distance distribution that is in agreement with the measured distribution.
Collapse
Affiliation(s)
- Theresa Sophie Braun
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
- Konstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Pia Widder
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
- Konstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Uwe Osswald
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Lina Groß
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Lara Williams
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Moritz Schmidt
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Irina Helmle
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
- Present address: Faculty of ScienceDepartment of Pharmaceutical BiologyUniversity of TübingenAuf der Morgenstelle 872076TübingenGermany
| | - Daniel Summerer
- Faculty of Chemistry and Chemical BiologyTU DortmundOtto-Hahn-Strasse 4a44227DortmundGermany
| | - Malte Drescher
- Department of ChemistryUniversity of KonstanzUniversitätsstrasse 1078457KonstanzGermany
- Konstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| |
Collapse
|
44
|
2-Butyl-2-tert-butyl-5,5-diethylpyrrolidine-1-oxyls: Synthesis and Properties. Molecules 2020; 25:molecules25040845. [PMID: 32075085 PMCID: PMC7070904 DOI: 10.3390/molecules25040845] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 02/13/2020] [Indexed: 12/04/2022] Open
Abstract
Nitroxides are broadly used as molecular probes and labels in biophysics, structural biology, and biomedical research. Resistance of a nitroxide group bearing an unpaired electron to chemical reduction with low-molecular-weight antioxidants and enzymatic systems is of critical importance for these applications. The redox properties of nitroxides are known to depend on the ring size (for cyclic nitroxides) and electronic and steric effects of the substituents. Here, two highly strained nitroxides, 5-(tert-butyl)-5-butyl-2,2-diethyl-3-hydroxypyrrolidin-1-oxyl (4) and 2-(tert-butyl)-2-butyl-5,5-diethyl-3,4-bis(hydroxymethyl)pyrrolidin-1-oxyl (5), were prepared via a reaction of the corresponding 2-tert-butyl-1-pyrroline 1-oxides with butyllithium. Thermal stability and kinetics of reduction of the new nitroxides by ascorbic acid were studied. Nitroxide 5 showed the highest resistance to reduction.
Collapse
|
45
|
Kucher S, Korneev S, Klare JP, Klose D, Steinhoff HJ. In cell Gd3+-based site-directed spin labeling and EPR spectroscopy of eGFP. Phys Chem Chem Phys 2020; 22:13358-13362. [DOI: 10.1039/d0cp01930e] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A newly synthesized Gd3+ chelate complex allows in cell spin labeling and detection of eGFP by EPR spectroscopy.
Collapse
Affiliation(s)
| | - Sergej Korneev
- Department of Biology
- Osnabrück University
- Osnabrück
- Germany
| | | | - Daniel Klose
- Department of Chemistry and Applied Biosciences
- ETH Zurich
- Zurich
- Switzerland
| | | |
Collapse
|
46
|
Kugele A, Silkenath B, Langer J, Wittmann V, Drescher M. Protein Spin Labeling with a Photocaged Nitroxide Using Diels-Alder Chemistry. Chembiochem 2019; 20:2479-2484. [PMID: 31090999 PMCID: PMC6790680 DOI: 10.1002/cbic.201900318] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Indexed: 12/31/2022]
Abstract
EPR spectroscopy of diamagnetic bio-macromolecules is based on site-directed spin labeling (SDSL). Herein, a novel labeling strategy for proteins is presented. A nitroxide-based spin label has been developed and synthesized that can be ligated to proteins by an inverse-electron-demand Diels-Alder (DAinv ) cycloaddition to genetically encoded noncanonical amino acids. The nitroxide moiety is shielded by a photoremovable protecting group with an attached tetra(ethylene glycol) unit to achieve water solubility. SDSL is demonstrated on two model proteins with the photoactivatable nitroxide for DAinv reaction (PaNDA) label. The strategy features high reaction rates, combined with high selectivity, and the possibility to deprotect the nitroxide in Escherichia coli lysate.
Collapse
Affiliation(s)
- Anandi Kugele
- Department of Chemistry andKonstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Bjarne Silkenath
- Department of Chemistry andKonstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Jakob Langer
- Department of Chemistry andKonstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Valentin Wittmann
- Department of Chemistry andKonstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| | - Malte Drescher
- Department of Chemistry andKonstanz Research School Chemical Biology (KoRS-CB)University of KonstanzUniversitätsstrasse 1078457KonstanzGermany
| |
Collapse
|
47
|
Bonucci A, Ouari O, Guigliarelli B, Belle V, Mileo E. In‐Cell EPR: Progress towards Structural Studies Inside Cells. Chembiochem 2019; 21:451-460. [DOI: 10.1002/cbic.201900291] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Indexed: 12/18/2022]
Affiliation(s)
- Alessio Bonucci
- Magnetic Resonance CenterCERMUniversity of Florence 50019 Sesto Fiorentino Italy
| | - Olivier Ouari
- Aix Marseille UnivCNRSICRInstitut de Chimie Radicalaire 13013 Marseille France
| | - Bruno Guigliarelli
- Aix Marseille UnivCNRSBIPBioénergétique et Ingénierie des ProtéinesIMM 13009 Marseille France
| | - Valérie Belle
- Aix Marseille UnivCNRSBIPBioénergétique et Ingénierie des ProtéinesIMM 13009 Marseille France
| | - Elisabetta Mileo
- Aix Marseille UnivCNRSBIPBioénergétique et Ingénierie des ProtéinesIMM 13009 Marseille France
| |
Collapse
|
48
|
Widder P, Berner F, Summerer D, Drescher M. Double Nitroxide Labeling by Copper-Catalyzed Azide-Alkyne Cycloadditions with Noncanonical Amino Acids for Electron Paramagnetic Resonance Spectroscopy. ACS Chem Biol 2019; 14:839-844. [PMID: 30998314 PMCID: PMC6534342 DOI: 10.1021/acschembio.8b01111] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 04/18/2019] [Indexed: 01/17/2023]
Abstract
Electron paramagnetic resonance spectroscopy in combination with site-directed spin labeling (SDSL) is an important tool to obtain long-range distance restraints for protein structural research. We here study a variety of azide- and alkyne-bearing noncanonical amino acids (ncAA) in terms of protein single- and double-incorporation efficiency via nonsense suppression, metabolic stability, yields of nitroxide labeling via copper-catalyzed [3 + 2] azide-alkyne cycloadditions (CuAAC), and spectroscopic properties in continuous-wave and double electron-electron resonance measurements. We identify para-ethynyl-l-phenylalanine and para-propargyloxy-l-phenylalanine as suitable ncAA for CuAAC-based SDSL that will complement current SDSL approaches, particularly in cases in which essential cysteines of a target protein prevent the use of sulfhydryl-reactive spin labels.
Collapse
Affiliation(s)
- Pia Widder
- Department
of Chemistry and Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Frederic Berner
- Department
of Chemistry and Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| | - Daniel Summerer
- Faculty
of Chemistry and Chemical Biology, TU Dortmund
University, Dortmund, Germany
| | - Malte Drescher
- Department
of Chemistry and Konstanz Research School Chemical Biology, University of Konstanz, Konstanz, Germany
| |
Collapse
|
49
|
Azarkh M, Bieber A, Qi M, Fischer JW, Yulikov M, Godt A, Drescher M. Gd(III)-Gd(III) Relaxation-Induced Dipolar Modulation Enhancement for In-Cell Electron Paramagnetic Resonance Distance Determination. J Phys Chem Lett 2019; 10:1477-1481. [PMID: 30864799 PMCID: PMC6625747 DOI: 10.1021/acs.jpclett.9b00340] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 03/13/2019] [Indexed: 05/26/2023]
Abstract
In-cell distance determination by electron paramagnetic resonance (EPR) spectroscopy reveals essential structural information about biomacromolecules under native conditions. We demonstrate that the pulsed EPR technique RIDME (relaxation induced dipolar modulation enhancement) can be utilized for such distance determination. The performance of in-cell RIDME has been assessed at Q-band using stiff molecular rulers labeled with Gd(III)-PyMTA and microinjected into Xenopus laevis oocytes. The overtone coefficients are determined to be the same for protonated aqueous solutions and inside cells. As compared to in-cell DEER (double electron-electron resonance, also abbreviated as PELDOR), in-cell RIDME features approximately 5 times larger modulation depth and does not show artificial broadening in the distance distributions due to the effect of pseudosecular terms.
Collapse
Affiliation(s)
- Mykhailo Azarkh
- Department
of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Anna Bieber
- Department
of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Mian Qi
- Faculty
of Chemistry and Center for Molecular Materials (CM2), Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Jörg W.
A. Fischer
- Department
of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| | - Maxim Yulikov
- Laboratory
of Physical Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland
| | - Adelheid Godt
- Faculty
of Chemistry and Center for Molecular Materials (CM2), Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Malte Drescher
- Department
of Chemistry, University of Konstanz, Universitätsstraße 10, 78457 Konstanz, Germany
| |
Collapse
|
50
|
Lawless MJ, Pettersson JR, Rule GS, Lanni F, Saxena S. ESR Resolves the C Terminus Structure of the Ligand-free Human Glutathione S-Transferase A1-1. Biophys J 2019; 114:592-601. [PMID: 29414705 DOI: 10.1016/j.bpj.2017.12.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 12/11/2017] [Accepted: 12/18/2017] [Indexed: 01/05/2023] Open
Abstract
Nitroxide- and Cu2+-based electron spin resonance (ESR) are combined to provide insight into the conformational states of the functionally important α-helix of the human glutathione S-transferase A1. Distance measurements on various spin-labeled dimeric human glutathione S-transferase A1-1 all result in bimodal distance distributions, indicating that the C-terminus exists in two distinct conformations in solution, one of which closely matches that found in the crystal structure of the ligand-bound enzyme. These measurements permit the generation of a model of the unliganded conformation. Room temperature ESR indicates that the second conformation has high mobility, potentially enabling the enzyme's high degree of substrate promiscuity. This model is then validated using computational modeling and further Cu2+-based ESR distance measurements. Cu2+-based ESR also provides evidence that the secondary structure of the second conformation is of helical nature. Addition of S-hexyl glutathione results in a shift in relative populations, favoring the state that is similar to the previously known structure of the ligand-bound enzyme.
Collapse
Affiliation(s)
- Matthew J Lawless
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - John R Pettersson
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Gordon S Rule
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Frederick Lanni
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania.
| |
Collapse
|