151
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Di Stasi R, Diana D, De Rosa L, Fattorusso R, D'Andrea LD. Biochemical and Conformational Characterization of Recombinant VEGFR2 Domain 7. Mol Biotechnol 2020; 61:860-872. [PMID: 31531759 DOI: 10.1007/s12033-019-00211-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Angiogenesis is a biological process finely tuned by a plethora of pro- and anti-angiogenic molecules, among which vascular endothelial growth factors (VEGFs). Their biological activity is expressed through the interaction with three cognate receptor tyrosine kinases, VEGFR1, 2, and 3. VEGFR2 is the primary regulator of angiogenesis. Ligand-induced VEGFR2 dimerization and activation depend on direct ligand binding to extracellular domains 2 and 3 of receptor and in the establishment of interactions between proximal membrane domains. VEGFR2 domain 7 has been shown to play a crucial role in receptor dimerization and regulation, therefore, representing a convenient target for the allosteric modulation of VEGFR2 activity. The ability to prepare a functional VEGFR2D7 domain represents the starting point to the development of novel VEGFR2 binders acting as allosteric inhibitors of receptor activity. Here, we describe a robust and efficient procedure for the preparation in E. coli of the VEGFR2 domain 7. The protein was obtained with a good yield and was properly folded. It was investigated in a biochemical and structural study, providing information on its conformational arrangement and in solution properties.
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Affiliation(s)
- Rossella Di Stasi
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy.
| | - Donatella Diana
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy
| | - Lucia De Rosa
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy
| | - Roberto Fattorusso
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università della Campania "L. Vanvitelli", Via Vivaldi, 43 - 81100, Caserta, Italy
| | - Luca D D'Andrea
- Istituto di Biostrutture e Bioimmagini, CNR, Via Mezzocannone 16, 80134, Naples, Italy.
- Istituto di Biostrutture e Bioimmagini, CNR, Via Nizza 52, 10126, Turin, Italy.
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152
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Munari F, D'Onofrio M, Assfalg M. Solution NMR insights into dynamic supramolecular assemblies of disordered amyloidogenic proteins. Arch Biochem Biophys 2020; 683:108304. [PMID: 32097611 DOI: 10.1016/j.abb.2020.108304] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/12/2020] [Accepted: 02/14/2020] [Indexed: 12/29/2022]
Abstract
The extraordinary flexibility and structural heterogeneity of intrinsically disordered proteins (IDP) make them functionally versatile molecules. We have now begun to better understand their fundamental role in biology, however many aspects of their behaviour remain difficult to grasp experimentally. This is especially true for the intermolecular interactions which lead to the formation of transient or highly dynamic supramolecular self-assemblies, such as oligomers, aggregation intermediates and biomolecular condensates. Both the emerging functions and pathogenicity of these structures have stimulated great efforts to develop methodologies capable of providing useful insights. Significant progress in solution NMR spectroscopy has made this technique one of the most powerful to describe structural and dynamic features of IDPs within such assemblies at atomic resolution. Here, we review the most recent works that have illuminated key aspects of IDP assemblies and contributed significant advancements towards our understanding of the complex conformational landscape of prototypical disease-associated proteins. We also include a primer on some of the fundamental and innovative NMR methods being used in the discussed studies.
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Affiliation(s)
- Francesca Munari
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - Mariapina D'Onofrio
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy
| | - Michael Assfalg
- Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
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153
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Multi-attribute PAT for UF/DF of Proteins-Monitoring Concentration, particle sizes, and Buffer Exchange. Anal Bioanal Chem 2020; 412:2123-2136. [PMID: 32072210 DOI: 10.1007/s00216-019-02318-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/25/2019] [Accepted: 12/03/2019] [Indexed: 01/08/2023]
Abstract
Ultrafiltration/diafiltration (UF/DF) plays an important role in the manufacturing of biopharmaceuticals. Monitoring critical process parameters and quality attributes by process analytical technology (PAT) during those steps can facilitate process development and assure consistent quality in production processes. In this study, a lab-scale cross-flow filtration (CFF) device was equipped with a variable pathlength (VP) ultraviolet and visible (UV/Vis) spectrometer, a light scattering photometer, and a liquid density sensor (microLDS). Based on the measured signals, the protein concentration, buffer exchange, apparent molecular weight, and hydrodynamic radius were monitored. The setup was tested in three case studies. First, lysozyme was used in an UF/DF run to show the comparability of on-line and off-line measurements. The corresponding correlation coefficients exceeded 0.97. Next, urea-induced changes in protein size of glucose oxidase (GOx) were monitored during two DF steps. Here, correlation coefficients were ≥ 0.92 for static light scattering (SLS) and dynamic light scattering (DLS). The correlation coefficient for the protein concentration was 0.82, possibly due to time-dependent protein precipitation. Finally, a case study was conducted with a monoclonal antibody (mAb) to show the full potential of this setup. Again, off-line and on-line measurements were in good agreement with all correlation coefficients exceeding 0.92. The protein concentration could be monitored in-line in a large range from 3 to 120 g L- 1. A buffer-dependent increase in apparent molecular weight of the mAb was observed during DF, providing interesting supplemental information for process development and stability assessment. In summary, the developed setup provides a powerful testing system for evaluating different UF/DF processes and may be a good starting point to develop process control strategies. Graphical Abstract Piping and instrumentation diagram of the experimental setup and data generated by the different sensors. A VP UV/Vis spectrometer (FlowVPE, yellow) measures the protein concentration. From the data of the light scattering photometer (Zetasizer, green) in the on-line measurement loop, the apparant molecular weight and z-average are calculated. The density sensor (microLDS) measures density and viscosity of the fluid in the on-line loop.
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154
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Ghadami SA, Chia S, Ruggeri FS, Meisl G, Bemporad F, Habchi J, Cascella R, Dobson CM, Vendruscolo M, Knowles TPJ, Chiti F. Transthyretin Inhibits Primary and Secondary Nucleations of Amyloid-β Peptide Aggregation and Reduces the Toxicity of Its Oligomers. Biomacromolecules 2020; 21:1112-1125. [PMID: 32011129 PMCID: PMC7997117 DOI: 10.1021/acs.biomac.9b01475] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
![]()
Alzheimer’s
disease is associated with the deposition of
the amyloid-β peptide (Aβ) into extracellular senile plaques
in the brain. In vitro and in vivo observations have indicated that
transthyretin (TTR) acts as an Aβ scavenger in the brain, but
the mechanism has not been fully resolved. We have monitored the aggregation
process of Aβ40 by thioflavin T fluorescence, in
the presence or absence of different concentrations of preformed seed
aggregates of Aβ40, of wild-type tetrameric TTR (WT-TTR),
and of a variant engineered to be stable as a monomer (M-TTR). Both
WT-TTR and M-TTR were found to inhibit specific steps of the process
of Aβ40 fibril formation, which are primary and secondary
nucleations, without affecting the elongation of the resulting fibrils.
Moreover, the analysis shows that both WT-TTR and M-TTR bind to Aβ40 oligomers formed in the aggregation reaction and inhibit
their conversion into the shortest fibrils able to elongate. Using
biophysical methods, TTR was found to change some aspects of its overall
structure following such interactions with Aβ40 oligomers,
as well as with oligomers of Aβ42, while maintaining
its overall topology. Hence, it is likely that the predominant mechanism
by which TTR exerts its protective role lies in the binding of TTR
to the Aβ oligomers and in inhibiting primary and secondary
nucleation processes, which limits both the toxicity of Aβ oligomers
and the ability of the fibrils to proliferate.
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Affiliation(s)
- Seyyed Abolghasem Ghadami
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Section of Biochemistry, University of Florence, 50134 Florence, Italy
| | - Sean Chia
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Francesco Simone Ruggeri
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Georg Meisl
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Francesco Bemporad
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Section of Biochemistry, University of Florence, 50134 Florence, Italy
| | - Johnny Habchi
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Roberta Cascella
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Section of Biochemistry, University of Florence, 50134 Florence, Italy
| | - Christopher M Dobson
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Michele Vendruscolo
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Tuomas P J Knowles
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge CB2 1EW, U.K.,Department of Physics, Cavendish Laboratory, 19 J. J. Thomson Avenue, Cambridge CB3 0HE, U.K
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", Section of Biochemistry, University of Florence, 50134 Florence, Italy
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155
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Raghunathan S, Jaganade T, Priyakumar UD. Urea-aromatic interactions in biology. Biophys Rev 2020; 12:65-84. [PMID: 32067192 PMCID: PMC7040157 DOI: 10.1007/s12551-020-00620-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 01/08/2020] [Indexed: 02/06/2023] Open
Abstract
Noncovalent interactions are key determinants in both chemical and biological processes. Among such processes, the hydrophobic interactions play an eminent role in folding of proteins, nucleic acids, formation of membranes, protein-ligand recognition, etc.. Though this interaction is mediated through the aqueous solvent, the stability of the above biomolecules can be highly sensitive to any small external perturbations, such as temperature, pressure, pH, or even cosolvent additives, like, urea-a highly soluble small organic molecule utilized by various living organisms to regulate osmotic pressure. A plethora of detailed studies exist covering both experimental and theoretical regimes, to understand how urea modulates the stability of biological macromolecules. While experimentalists have been primarily focusing on the thermodynamic and kinetic aspects, theoretical modeling predominantly involves mechanistic information at the molecular level, calculating atomistic details applying the force field approach to the high level electronic details using the quantum mechanical methods. The review focuses mainly on examples with biological relevance, such as (1) urea-assisted protein unfolding, (2) urea-assisted RNA unfolding, (3) urea lesion interaction within damaged DNA, (4) urea conduction through membrane proteins, and (5) protein-ligand interactions those explicitly address the vitality of hydrophobic interactions involving exclusively the urea-aromatic moiety.
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Affiliation(s)
- Shampa Raghunathan
- Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Hyderabad, 500032, India
| | - Tanashree Jaganade
- Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Hyderabad, 500032, India
| | - U Deva Priyakumar
- Center for Computational Natural Sciences and Bioinformatics, International Institute of Information Technology, Hyderabad, 500032, India.
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156
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Stingaciu LR, Biehl R, Changwoo D, Richter D, Stadler AM. Reduced Internal Friction by Osmolyte Interaction in Intrinsically Disordered Myelin Basic Protein. J Phys Chem Lett 2020; 11:292-296. [PMID: 31841337 DOI: 10.1021/acs.jpclett.9b03001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Urea is a strong denaturing osmolyte that disrupts noncovalent bonds in proteins. Here, we present a small-angle neutron scattering (SANS) and neutron spin-echo spectroscopy (NSE) study on the structure and dynamics of the intrinsically disordered myelin basic protein (MBP) denatured by urea. SANS results show that urea-denatured MBP is more compact than ideal polymers, while its secondary structure content is entirely lost. NSE experiments reveal concomitantly an increase of the relaxation time and of the amplitude of internal motions in urea-denatured MBP as compared to native MBP. If interpreted in terms of the Zimm model including internal friction (ZIF), the internal friction parameter decreased by a factor of 6.5. Urea seems to not only smooth local energy barriers, reducing internal friction on a local scale, but also significantly reduces the overall depth of the global energy landscape. This leads to a nearly complete loss of restoring forces beyond entropic forces and in turn allows for larger motional amplitudes. Obviously, the noncovalent H-bonds are largely eliminated, driving the unfolded protein to be more similar to a synthetic polymer.
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Affiliation(s)
- Laura R Stingaciu
- NScD, SNS , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
| | - Ralf Biehl
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1) , Forschungszentrum Jülich GmbH , 52425 Jülich , Germany
| | - Do Changwoo
- NScD, SNS , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37830 , United States
| | - Dieter Richter
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1) , Forschungszentrum Jülich GmbH , 52425 Jülich , Germany
| | - Andreas M Stadler
- Jülich Centre for Neutron Science (JCNS-1) and Institute for Complex Systems (ICS-1) , Forschungszentrum Jülich GmbH , 52425 Jülich , Germany
- Institute of Physical Chemistry , RWTH Aachen University , Landoltweg 2 , 52056 Aachen , Germany
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157
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V. Khorolskyi O, P. Malomuzh N. Macromolecular sizes of serum albumins in its aqueous solutions. AIMS BIOPHYSICS 2020. [DOI: 10.3934/biophy.2020017] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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158
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Ahmed MC, Crehuet R, Lindorff-Larsen K. Computing, Analyzing, and Comparing the Radius of Gyration and Hydrodynamic Radius in Conformational Ensembles of Intrinsically Disordered Proteins. Methods Mol Biol 2020; 2141:429-445. [PMID: 32696370 DOI: 10.1007/978-1-0716-0524-0_21] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The level of compaction of an intrinsically disordered protein may affect both its physical and biological properties, and can be probed via different types of biophysical experiments. Small-angle X-ray scattering (SAXS) probe the radius of gyration (Rg) whereas pulsed-field-gradient nuclear magnetic resonance (NMR) diffusion, fluorescence correlation spectroscopy, and dynamic light scattering experiments can be used to determine the hydrodynamic radius (Rh). Here we show how to calculate Rg and Rh from a computationally generated conformational ensemble of an intrinsically disordered protein. We further describe how to use a Bayesian/Maximum Entropy procedure to integrate data from SAXS and NMR diffusion experiments, so as to derive conformational ensembles in agreement with those experiments.
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Affiliation(s)
- Mustapha Carab Ahmed
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Ramon Crehuet
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
- Institute for Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona, Spain
| | - Kresten Lindorff-Larsen
- Structural Biology and NMR Laboratory, Linderstrøm-Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen N, Denmark.
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159
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Millard PS, Bugge K, Marabini R, Boomsma W, Burow M, Kragelund BB. IDDomainSpotter: Compositional bias reveals domains in long disordered protein regions-Insights from transcription factors. Protein Sci 2020; 29:169-183. [PMID: 31642121 PMCID: PMC6933863 DOI: 10.1002/pro.3754] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 10/16/2019] [Accepted: 10/16/2019] [Indexed: 12/12/2022]
Abstract
Protein domains constitute regions of distinct structural properties and molecular functions that are retained when removed from the rest of the protein. However, due to the lack of tertiary structure, the identification of domains has been largely neglected for long (>50 residues) intrinsically disordered regions. Here we present a sequence-based approach to assess and visualize domain organization in long intrinsically disordered regions based on compositional sequence biases. An online tool to find putative intrinsically disordered domains (IDDomainSpotter) in any protein sequence or sequence alignment using any particular sequence trait is available at http://www.bio.ku.dk/sbinlab/IDDomainSpotter. Using this tool, we have identified a putative domain enriched in hydrophilic and disorder-promoting residues (Pro, Ser, and Thr) and depleted in positive charges (Arg and Lys) bordering the folded DNA-binding domains of several transcription factors (p53, GCR, NAC46, MYB28, and MYB29). This domain, from two different MYB transcription factors, was characterized biophysically to determine its properties. Our analyses show the domain to be extended, dynamic and highly disordered. It connects the DNA-binding domain to other disordered domains and is present and conserved in several transcription factors from different families and domains of life. This example illustrates the potential of IDDomainSpotter to predict, from sequence alone, putative domains of functional interest in otherwise uncharacterized disordered proteins.
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Affiliation(s)
- Peter S. Millard
- DynaMo Center, Department of Plant and Environmental SciencesUniversity of CopenhagenCopenhagenDenmark
- Copenhagen Plant Science Centre, Department of Plant and Environmental SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Katrine Bugge
- Structural Biology and NMR Laboratory, Department of BiologyUniversity of CopenhagenCopenhagenDenmark
| | - Riccardo Marabini
- Structural Biology and NMR Laboratory, Department of BiologyUniversity of CopenhagenCopenhagenDenmark
| | - Wouter Boomsma
- Department of Computer ScienceUniversity of CopenhagenCopenhagenDenmark
| | - Meike Burow
- DynaMo Center, Department of Plant and Environmental SciencesUniversity of CopenhagenCopenhagenDenmark
- Copenhagen Plant Science Centre, Department of Plant and Environmental SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Birthe B. Kragelund
- Structural Biology and NMR Laboratory, Department of BiologyUniversity of CopenhagenCopenhagenDenmark
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160
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Obtaining Hydrodynamic Radii of Intrinsically Disordered Protein Ensembles by Pulsed Field Gradient NMR Measurements. Methods Mol Biol 2020; 2141:285-302. [PMID: 32696363 DOI: 10.1007/978-1-0716-0524-0_14] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
In the disordered state, a protein exhibits a high degree of structural freedom, in both space and time. For an ensemble of disordered or unfolded proteins, this means that the ensemble comprises a high diversity of structures, ranging from compact collapsed states to fully extended polypeptide chains. In addition, each chain is highly dynamic and undergoes conformational changes and local dynamics on both fast and slow timescales. The size properties of disordered proteins are thus best described as ensemble averages. A straightforward measure of the size is the hydrodynamic radius, RH, of the ensemble. Since the disordered state is conformationally fluid, the observed RH does not refer to a particular shape or fold. Instead, it should be interpreted as a measure for the average compaction of the structural ensemble. In addition to characterizing the disordered ensemble itself, RH can be used to, with good precision, monitor changes in the ensemble size properties upon functional interactions of the disordered protein, e.g., dimerization, ligand binding, and folding pathways. Here, we present a step-by-step protocol for diffusion measurements using pulsed field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. We describe how to calibrate the magnetic field gradient and offer different schemes for sample preparation. Finally, we describe how to obtain RH directly from the diffusion coefficient as well as from using an internal standard as a reference.
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161
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Rho Y, Kim JH, Min B, Jin KS. Chemically Denatured Structures of Porcine Pepsin using Small-Angle X-ray Scattering. Polymers (Basel) 2019; 11:polym11122104. [PMID: 31847418 PMCID: PMC6961028 DOI: 10.3390/polym11122104] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 11/16/2022] Open
Abstract
Porcine pepsin is a gastric aspartic proteinase that reportedly plays a pivotal role in the digestive process of many vertebrates. We have investigated the three-dimensional (3D) structure and conformational transition of porcine pepsin in solution over a wide range of denaturant urea concentrations (0–10 M) using Raman spectroscopy and small-angle X-ray scattering. Furthermore, 3D GASBOR ab initio structural models, which provide an adequate conformational description of pepsin under varying denatured conditions, were successfully constructed. It was shown that pepsin molecules retain native conformation at 0–5 M urea, undergo partial denaturation at 6 M urea, and display a strongly unfolded conformation at 7–10 M urea. According to the resulting GASBOR solution models, we identified an intermediate pepsin conformation that was dominant during the early stage of denaturation. We believe that the structural evidence presented here provides useful insights into the relationship between enzymatic activity and conformation of porcine pepsin at different states of denaturation.
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Affiliation(s)
- Yecheol Rho
- Chemical Analysis Center, Korea Research Institute of Chemical Technology, 141, Gajeong-ro, Yuseong-gu, Daejeon 34114, Korea;
| | - Jun Ha Kim
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, 80 Jigokro-127-beongil, Nam-Gu, Pohang, Kyungbuk 37673, Korea; (J.H.K.); (B.M.)
| | - Byoungseok Min
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, 80 Jigokro-127-beongil, Nam-Gu, Pohang, Kyungbuk 37673, Korea; (J.H.K.); (B.M.)
| | - Kyeong Sik Jin
- Pohang Accelerator Laboratory, Pohang University of Science and Technology, 80 Jigokro-127-beongil, Nam-Gu, Pohang, Kyungbuk 37673, Korea; (J.H.K.); (B.M.)
- Correspondence: ; Tel.: +82-54-279-1573; Fax: +82-54-279-1599
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162
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Andrews J, Blaisten-Barojas E. Exploring with Molecular Dynamics the Structural Fate of PLGA Oligomers in Various Solvents. J Phys Chem B 2019; 123:10233-10244. [PMID: 31702156 DOI: 10.1021/acs.jpcb.9b06681] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This study focuses on the solvent effects that promote preferred solvated structures of polylactic-co-glycolic acid (PLGA) oligomers of molecular weight 278, 668, and 1449 u in ethyl acetate, water, and a mixture of both solvents. Our methodology consists of all-atom, explicit solvent molecular dynamics simulations for inspection of the solvated oligomer structures at ambient conditions. Parameters for the generalized Amber force field are developed in this work for the ethyl acetate liquid and the PLGA oligomers. Energetics, oligomer radius of gyration, end-to-end distance, orientational order parameter, flexibility coefficient, and backbone dihedral angles are reported along with a size scaling property yielding a power law for PLGA oligomers in each of the three solvents considered. It is found that the PLGA oligomer has two characteristic states identified by a set of extended structures and a set of collapsed structures, the former being energetically preferred in ethyl acetate and its mixture with water. The two types of PLGA structures occur in the three solvents and although they flip from one to the other in a sporadic fashion, in ethyl acetate, the extended structures may persist for more than 20 ns. The collapsed structures are significantly more frequent in water, occurring seldom in the mixed ethyl acetate-water solvent. PLGA is a biodegradable polymer approved for use in pharmaceutical and biomedical applications. Insights provided therein are of importance for the polymer aggregation process and its glassy state in condensed phases.
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Affiliation(s)
- James Andrews
- Center for Simulation and Modeling (formerly, Computational Materials Science Center) and Department of Computational and Data Sciences , George Mason University , Fairfax , Virginia 22030 , United States
| | - Estela Blaisten-Barojas
- Center for Simulation and Modeling (formerly, Computational Materials Science Center) and Department of Computational and Data Sciences , George Mason University , Fairfax , Virginia 22030 , United States
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163
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Wiedenbeck E, Kovermann M, Gebauer D, Cölfen H. Flüssige metastabile Vorstufen von Ibuprofen als Zwischenprodukt der Nukleation in wässriger Lösung. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201910986] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Eduard Wiedenbeck
- Physical ChemistryUniversity of Konstanz Universitätsstraße 10 78457 Konstanz Deutschland
| | - Michael Kovermann
- Physical ChemistryUniversity of Konstanz Universitätsstraße 10 78457 Konstanz Deutschland
| | - Denis Gebauer
- Leibniz University of Hannover, Institut für Anorganische Chemie Callinstraße 9 30167 Hannover Deutschland
| | - Helmut Cölfen
- Physical ChemistryUniversity of Konstanz Universitätsstraße 10 78457 Konstanz Deutschland
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164
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Wiedenbeck E, Kovermann M, Gebauer D, Cölfen H. Liquid Metastable Precursors of Ibuprofen as Aqueous Nucleation Intermediates. Angew Chem Int Ed Engl 2019; 58:19103-19109. [PMID: 31556970 PMCID: PMC6972611 DOI: 10.1002/anie.201910986] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Indexed: 01/25/2023]
Abstract
The nucleation mechanism of crystals of small organic molecules, postulated based on computer simulations, still lacks experimental evidence. In this study we designed an experimental approach to monitor the early stages of the crystallization of ibuprofen as a model system for small organic molecules. Ibuprofen undergoes liquid–liquid phase separation prior to nucleation. The binodal and spinodal limits of the corresponding liquid–liquid miscibility gap were analyzed and confirmed. An increase in viscosity sustains the kinetic stability of the dense liquid intermediate. Since the distances between ibuprofen molecules within the dense liquid phase are similar to those in the crystal forms, this dense liquid phase is identified as a precursor phase in the nucleation of ibuprofen, in which densification is followed by generation of structural order. This discovery may make it possible to enrich poorly soluble pharmaceuticals beyond classical solubility limitations in aqueous environments.
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Affiliation(s)
- Eduard Wiedenbeck
- Physical Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Michael Kovermann
- Physical Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
| | - Denis Gebauer
- Leibniz University of Hannover, Institute of Inorganic Chemistry, Callinstraße 9, 30167, Hannover, Germany
| | - Helmut Cölfen
- Physical Chemistry, University of Konstanz, Universitätsstraße 10, 78457, Konstanz, Germany
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165
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Arbesú M, Pons M. Integrating disorder in globular multidomain proteins: Fuzzy sensors and the role of SH3 domains. Arch Biochem Biophys 2019; 677:108161. [PMID: 31678340 DOI: 10.1016/j.abb.2019.108161] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 10/20/2019] [Accepted: 10/24/2019] [Indexed: 12/25/2022]
Abstract
Intrinsically disordered proteins represent about one third of eukaryotic proteins. An additional third correspond to proteins containing folded domains as well as large intrinsically disordered regions (IDR). While IDRs may represent functionally autonomous domains, in some instances it has become clear that they provide a new layer of regulation for the activity displayed by the folded domains. The sensitivity of the conformational ensembles defining the properties of IDR to small changes in the cellular environment and the capacity to modulate this response through post-translational modifications makes IDR ideal sensors enabling continuous, integrative responses to complex cellular inputs. Folded domains (FD), on the other hand, are ideal effectors, e.g. by catalyzing enzymatic reactions or participating in binary on/off switches. In this perspective review we discuss the possible role of intramolecular fuzzy complexes to integrate the very different dynamic scales of IDR and FD, inspired on the recent observations of such dynamic complexes in Src family kinases, and we explore the possible general role of the SH3 domains connecting IDRs and FD.
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Affiliation(s)
- Miguel Arbesú
- Biomolecular NMR laboratory. Department of Inorganic and Organic Chemistry. University of Barcelona, Baldiri Reixac, 10-12, 08028, Barcelona, Spain
| | - Miquel Pons
- Biomolecular NMR laboratory. Department of Inorganic and Organic Chemistry. University of Barcelona, Baldiri Reixac, 10-12, 08028, Barcelona, Spain.
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166
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Imranpasha, Kumar B. Kinetics of interaction between antimicrobial peptide nisin and Langmuir monolayers of DPPC and DPPG molecules. Phys Rev E 2019; 100:032404. [PMID: 31640048 DOI: 10.1103/physreve.100.032404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Indexed: 11/07/2022]
Abstract
We have studied the kinetics of the interaction between antimicrobial peptide nisin and Langmuir monolayers of phospholipids DPPC and DPPG at the air-water interface using the surface manometry technique. The charge on the nisin and the lipid molecules is controlled by varying the pH of the subphase, and the interactions between them are studied by measuring the surface pressure of the lipid monolayer as a function of time after injecting the nisin in the subphase. A model based on the diffusion of particles under the influence of a constant force is developed to obtain an analytical expression for surface pressure as a function of time. The expression was found to fit well with the experimental data. The average hydrodynamic radius and the translational diffusion constant of the nisin molecules are calculated from the fit parameters for the different subphase pH solutions.
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Affiliation(s)
- Imranpasha
- Department of Physics, Central University of Karnataka, Kadaganchi-585367, Kalaburagi, Karnataka, India
| | - Bharat Kumar
- Department of Physics, Central University of Karnataka, Kadaganchi-585367, Kalaburagi, Karnataka, India
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167
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Elnahriry KA, Wai DC, Krishnarjuna B, Badawy NN, Chittoor B, MacRaild CA, Williams-Noonan BJ, Surm JM, Chalmers DK, Zhang AH, Peigneur S, Mobli M, Tytgat J, Prentis P, Norton RS. Structural and functional characterisation of a novel peptide from the Australian sea anemone Actinia tenebrosa. Toxicon 2019; 168:104-112. [DOI: 10.1016/j.toxicon.2019.07.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 06/29/2019] [Accepted: 07/08/2019] [Indexed: 12/11/2022]
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168
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Pessina F, Giavazzi F, Yin Y, Gioia U, Vitelli V, Galbiati A, Barozzi S, Garre M, Oldani A, Flaus A, Cerbino R, Parazzoli D, Rothenberg E, d'Adda di Fagagna F. Functional transcription promoters at DNA double-strand breaks mediate RNA-driven phase separation of damage-response factors. Nat Cell Biol 2019; 21:1286-1299. [PMID: 31570834 PMCID: PMC6859070 DOI: 10.1038/s41556-019-0392-4] [Citation(s) in RCA: 210] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 08/16/2019] [Indexed: 12/31/2022]
Abstract
Damage-induced long non-coding RNAs (dilncRNA) synthesized at DNA double-strand breaks (DSBs) by RNA polymerase II are necessary for DNA-damage-response (DDR) focus formation. We demonstrate that induction of DSBs results in the assembly of functional promoters that include a complete RNA polymerase II preinitiation complex, MED1 and CDK9. Absence or inactivation of these factors causes a reduction in DDR foci both in vivo and in an in vitro system that reconstitutes DDR events on nucleosomes. We also show that dilncRNAs drive molecular crowding of DDR proteins, such as 53BP1, into foci that exhibit liquid-liquid phase-separation condensate properties. We propose that the assembly of DSB-induced transcriptional promoters drives RNA synthesis, which stimulates phase separation of DDR factors in the shape of foci.
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Affiliation(s)
- Fabio Pessina
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy
| | - Fabio Giavazzi
- Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, Segrate, Italy
| | - Yandong Yin
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
| | - Ubaldo Gioia
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy
| | - Valerio Vitelli
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy
| | | | - Sara Barozzi
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy
| | | | - Amanda Oldani
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy
| | - Andrew Flaus
- Centre for Chromosome Biology, Biochemistry, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Roberto Cerbino
- Dipartimento di Biotecnologie Mediche e Medicina Traslazionale, Università degli Studi di Milano, Segrate, Italy
| | - Dario Parazzoli
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy
| | - Eli Rothenberg
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY, USA
| | - Fabrizio d'Adda di Fagagna
- IFOM, The FIRC Institute of Molecular Oncology, Milan, Italy.
- Istituto di Genetica Molecolare, CNR-Consiglio Nazionale delle Ricerche, Pavia, Italy.
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169
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Dzuricky M, Xiong S, Weber P, Chilkoti A. Avidity and Cell Uptake of Integrin-Targeting Polypeptide Micelles is Strongly Shape-Dependent. NANO LETTERS 2019; 19:6124-6132. [PMID: 31389705 DOI: 10.1021/acs.nanolett.9b02095] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We describe a genetically encoded micelle for targeted delivery consisting of a diblock polypeptide with segments derived from repetitive protein motifs inspired by Drosophila melanogaster Rec-1 resilin and human tropoelastin with a C-terminal fusion of an integrin-targeting fibronectin type III domain. By systematically varying the weight fraction of the hydrophilic elastin-like polypeptide (ELP) block and molecular weight of the diblock polypeptide, we designed micelles of different morphologies that modulate the binding avidity of the human wild-type 10th fibronectin domain (Fn3) as a function of shape. We show that wormlike micelles that present the Fn3 domain have a 1000-fold greater avidity for the αvβ3 receptor compared to the monomer ligand and an avidity that is greater than a clinically relevant antibody that is driven by their multivalency. The amplified avidity of these micelles leads to significantly increased cellular internalization, a feature that may have utility for the intracellular delivery of drugs that are loaded into the core of these micelles.
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Affiliation(s)
- Michael Dzuricky
- Department of Biomedical Engineering , Duke University , Durham , North Carolina 27708 , United States
| | - Sinan Xiong
- Department of Biomedical Engineering , Duke University , Durham , North Carolina 27708 , United States
| | - Patrick Weber
- Department of Biomedical Engineering , Duke University , Durham , North Carolina 27708 , United States
- Swiss Nanoscience Institute , University of Basel , Basel 4056 , Switzerland
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering , Duke University , Durham , North Carolina 27708 , United States
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170
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Mobility of pectin methylesterase in pectin/cellulose gels is enhanced by the presence of cellulose and by its catalytic capacity. Sci Rep 2019; 9:12551. [PMID: 31467440 PMCID: PMC6715659 DOI: 10.1038/s41598-019-49108-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 08/12/2019] [Indexed: 11/17/2022] Open
Abstract
The pectin methylesterase action is usually studied in a homogeneous aqueous medium in the presence of a large excess of soluble substrate and water. However in the cell wall, the water content is much lower, the substrate is cross-linked with itself or with other polymers, and the enzyme has to diffuse through the solid matrix before catalysing the linkage breakdown. As plant primary cell walls can be considered as cellulose-reinforced hydrogels, this study investigated the diffusion of a fungal pectin methylesterase in pectin/cellulose gels used as cell wall-mimicking matrix to understand the impact of this matrix and its (micro) structure on the enzyme’s diffusion within it. The enzyme mobility was followed by synchrotron microscopy thanks to its auto-fluorescence after deep-UV excitation. Time-lapse imaging and quantification of intensity signal by image analysis revealed that the diffusion of the enzyme was impacted by at least two criteria: (i) only the active enzyme was able to diffuse, showing that the mobility was related to the catalytic ability, and (ii) the diffusion was improved by the presence of cellulose in the gel.
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171
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Majumder S, Hansmann UHE, Janke W. Pearl-Necklace-Like Local Ordering Drives Polypeptide Collapse. Macromolecules 2019; 52:5491-5498. [PMID: 31631912 PMCID: PMC6795215 DOI: 10.1021/acs.macromol.9b00562] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/31/2019] [Indexed: 11/30/2022]
Abstract
![]()
The
collapse of the polypeptide backbone is an integral part of
protein folding. Using polyglycine as a probe, we explore the nonequilibrium
pathways of protein collapse in water. We find that the collapse depends
on the competition between hydration effects and intrapeptide interactions.
Once intrapeptide van der Waal interactions dominate, the chain collapses
along a nonequilibrium pathway characterized by formation of pearl-necklace-like
local clusters as intermediates that eventually coagulate into a single
globule. By describing this coarsening through the contact probability
as a function of distance along the chain, we extract a time-dependent
length scale that grows in a linear fashion. The collapse dynamics
is characterized by a dynamical critical exponent z ≈ 0.5 that is much smaller than the values of z = 1–2 reported for nonbiological polymers. This difference
in the exponents is explained by the instantaneous formation of intrachain
hydrogen bonds and local ordering that may be correlated with the
observed fast folding times of proteins.
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Affiliation(s)
- Suman Majumder
- Institut für Theoretische Physik, Universität Leipzig, IPF 231101, 04081 Leipzig, Germany
| | - Ulrich H E Hansmann
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Wolfhard Janke
- Institut für Theoretische Physik, Universität Leipzig, IPF 231101, 04081 Leipzig, Germany
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172
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Schramm A, Bignon C, Brocca S, Grandori R, Santambrogio C, Longhi S. An arsenal of methods for the experimental characterization of intrinsically disordered proteins - How to choose and combine them? Arch Biochem Biophys 2019; 676:108055. [PMID: 31356778 DOI: 10.1016/j.abb.2019.07.020] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/16/2019] [Accepted: 07/24/2019] [Indexed: 12/12/2022]
Abstract
In this review, we detail the most common experimental approaches to assess and characterize protein intrinsic structural disorder, with the notable exception of NMR and EPR spectroscopy, two ideally suited approaches that will be described in depth in two other reviews within this special issue. We discuss the advantages, the limitations, as well as the caveats of the various methods. We also describe less common and more demanding approaches that enable achieving further insights into the conformational properties of IDPs. Finally, we present recent developments that have enabled assessment of structural disorder in living cells, and discuss the currently available methods to model IDPs as conformational ensembles.
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Affiliation(s)
- Antoine Schramm
- CNRS and Aix-Marseille Univ, Laboratoire Architecture et Fonction des Macromolecules Biologiques (AFMB), UMR 7257, Marseille, France
| | - Christophe Bignon
- CNRS and Aix-Marseille Univ, Laboratoire Architecture et Fonction des Macromolecules Biologiques (AFMB), UMR 7257, Marseille, France
| | - Stefania Brocca
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Rita Grandori
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Carlo Santambrogio
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Sonia Longhi
- CNRS and Aix-Marseille Univ, Laboratoire Architecture et Fonction des Macromolecules Biologiques (AFMB), UMR 7257, Marseille, France.
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173
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Vega MV, Nigro A, Luti S, Capitini C, Fani G, Gonnelli L, Boscaro F, Chiti F. Isolation and characterization of soluble human full‐length TDP‐43 associated with neurodegeneration. FASEB J 2019; 33:10780-10793. [DOI: 10.1096/fj.201900474r] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Mirella Vivoli Vega
- Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceFlorenceItaly
| | - Alessia Nigro
- Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceFlorenceItaly
| | - Simone Luti
- Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceFlorenceItaly
| | - Claudia Capitini
- Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceFlorenceItaly
| | - Giulia Fani
- Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceFlorenceItaly
| | - Leonardo Gonnelli
- Centro di Ricerca di Risonanze Magnetiche (CERM)University of FlorenceFlorenceItaly
| | | | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical SciencesUniversity of FlorenceFlorenceItaly
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174
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Nolan V, Clop PD, Burgos MI, Perillo MA. Dual substrate/solvent- roles of water and mixed reaction-diffusion control of β-Galactosidase catalyzed reactions in PEG-induced macromolecular crowding conditions. Biochem Biophys Res Commun 2019; 515:190-195. [DOI: 10.1016/j.bbrc.2019.05.081] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 05/10/2019] [Indexed: 12/21/2022]
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175
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Murthy AC, Dignon GL, Kan Y, Zerze GH, Parekh SH, Mittal J, Fawzi NL. Molecular interactions underlying liquid-liquid phase separation of the FUS low-complexity domain. Nat Struct Mol Biol 2019; 26:637-648. [PMID: 31270472 PMCID: PMC6613800 DOI: 10.1038/s41594-019-0250-x] [Citation(s) in RCA: 375] [Impact Index Per Article: 75.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 05/14/2019] [Indexed: 12/12/2022]
Abstract
The low complexity domain of the RNA-binding protein FUS (FUS LC) mediates liquid-liquid phase separation (LLPS), but interactions between the repetitive SYGQ-rich sequence of FUS LC that stabilize the liquid phase are not known in detail. By combining NMR and Raman spectroscopy, mutagenesis, and molecular simulation, we demonstrate that heterogeneous interactions involving all residue types underlie LLPS of human FUS LC. We find no evidence that FUS LC adopts conformations with traditional secondary structure elements in the condensed phase, rather it maintains conformational heterogeneity. We show that hydrogen bonding, π/sp2 and hydrophobic interactions all contribute to stabilizing LLPS of FUS LC. In addition to contributions from tyrosine residues, we find that glutamine residues participate in contacts leading to LLPS of FUS LC. These results support a model in which FUS LC forms dynamic, multivalent interactions via multiple residue types and remains disordered in the densely packed liquid phase.
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Affiliation(s)
- Anastasia C Murthy
- Graduate Program in Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Gregory L Dignon
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, USA
| | - Yelena Kan
- LUT School of Engineering Science, LUT University, Lappeenranta, Finland.,Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany
| | - Gül H Zerze
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, USA.,Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - Sapun H Parekh
- Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.,Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA
| | - Jeetain Mittal
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, USA.
| | - Nicolas L Fawzi
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI, USA.
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176
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Rezaei-Ghaleh N, Parigi G, Zweckstetter M. Reorientational Dynamics of Amyloid-β from NMR Spin Relaxation and Molecular Simulation. J Phys Chem Lett 2019; 10:3369-3375. [PMID: 31181936 PMCID: PMC6598774 DOI: 10.1021/acs.jpclett.9b01050] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Amyloid-β (Aβ) aggregation is a hallmark of Alzheimer's disease. As an intrinsically disordered protein, Aβ undergoes extensive dynamics on multiple length and time scales. Access to a comprehensive picture of the reorientational dynamics in Aβ requires therefore the combination of complementary techniques. Here, we integrate 15N spin relaxation rates at three magnetic fields with microseconds-long molecular dynamics simulation, ensemble-based hydrodynamic calculations, and previously published nanosecond fluorescence correlation spectroscopy to investigate the reorientational dynamics of Aβ1-40 (Aβ40) at single-residue resolution. The integrative analysis shows that librational and dihedral angle fluctuations occurring at fast and intermediate time scales are not sufficient to decorrelate orientational memory in Aβ40. Instead, slow segmental motions occurring at ∼5 ns are detected throughout the Aβ40 sequence and reach up to ∼10 ns for selected residues. We propose that the modulation of time scales of reorientational dynamics with respect to intra- and intermolecular diffusion plays an important role in disease-related Aβ aggregation.
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Affiliation(s)
- Nasrollah Rezaei-Ghaleh
- Department
of Neurology, University Medical Center
Goettingen, 37075 Goettingen, Germany
- Department
for NMR-Based Structural Biology, Max Planck
Institute for Biophysical Chemistry, 37077 Goettingen, Germany
- E-mail:
| | - Giacomo Parigi
- Magnetic
Resonance Center (CERM) and Department of Chemistry “Ugo Schiff”, University of Florence, via Sacconi 6, 50019 Sesto Fiorentino, Italy
| | - Markus Zweckstetter
- Department
of Neurology, University Medical Center
Goettingen, 37075 Goettingen, Germany
- Department
for NMR-Based Structural Biology, Max Planck
Institute for Biophysical Chemistry, 37077 Goettingen, Germany
- Research
Group for Structural Biology in Dementia, German Center for Neurodegenerative Diseases (DZNE) Goettingen, 37075 Goettingen, Germany
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177
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Abstract
AbstractThe dynamics of proteins in solution includes a variety of processes, such as backbone and side-chain fluctuations, interdomain motions, as well as global rotational and translational (i.e. center of mass) diffusion. Since protein dynamics is related to protein function and essential transport processes, a detailed mechanistic understanding and monitoring of protein dynamics in solution is highly desirable. The hierarchical character of protein dynamics requires experimental tools addressing a broad range of time- and length scales. We discuss how different techniques contribute to a comprehensive picture of protein dynamics, and focus in particular on results from neutron spectroscopy. We outline the underlying principles and review available instrumentation as well as related analysis frameworks.
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178
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Nesmelova IV, Melnikova DL, Ranjan V, Skirda VD. Translational diffusion of unfolded and intrinsically disordered proteins. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 166:85-108. [PMID: 31521238 DOI: 10.1016/bs.pmbts.2019.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Translational (or self-diffusion) coefficient in dilute solution is inversely proportional to the size of a diffusing molecule, and hence self-diffusion coefficient measurements have been applied to determine the effective hydrodynamic radii for a range of native and nonnative protein conformations. In particular, translational diffusion coefficient measurements are useful to estimate the hydrodynamic radius of natively (or intrinsically) disordered proteins in solution, and, thereby, probe the compactness of a protein as well as its change when environmental parameters such as temperature, solution pH, or protein concentration are varied. The situation becomes more complicated in concentrated solutions. In this review, we discuss the translational diffusion of disordered proteins in dilute and crowded solutions, focusing primarily on the information provided by pulsed-field gradient NMR technique, and draw analogies to well-structured globular proteins and synthetic polymers.
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Affiliation(s)
- Irina V Nesmelova
- Department of Physics and Optical Sciences, University of North Carolina, Charlotte, NC, United States; Center for Biomedical Engineering and Science, University of North Carolina, Charlotte, NC, United States.
| | | | - Venkatesh Ranjan
- Department of Chemistry, University of North Carolina, Charlotte, NC, United States
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179
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Humphreys SC, Thayer MB, Lade JM, Wu B, Sham K, Basiri B, Hao Y, Huang X, Smith R, Rock BM. Plasma and Liver Protein Binding of N-Acetylgalactosamine–Conjugated Small Interfering RNA. Drug Metab Dispos 2019; 47:1174-1182. [DOI: 10.1124/dmd.119.086967] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/06/2019] [Indexed: 12/20/2022] Open
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180
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Modeling the Tertiary Structure of the Rift Valley Fever Virus L Protein. Molecules 2019; 24:molecules24091768. [PMID: 31067727 PMCID: PMC6539450 DOI: 10.3390/molecules24091768] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/13/2019] [Accepted: 05/03/2019] [Indexed: 01/09/2023] Open
Abstract
A tertiary structure governs, to a great extent, the biological activity of a protein in the living cell and is consequently a central focus of numerous studies aiming to shed light on cellular processes central to human health. Here, we aim to elucidate the structure of the Rift Valley fever virus (RVFV) L protein using a combination of in silico techniques. Due to its large size and multiple domains, elucidation of the tertiary structure of the L protein has so far challenged both dry and wet laboratories. In this work, we leverage complementary perspectives and tools from the computational-molecular-biology and bioinformatics domains for constructing, refining, and evaluating several atomistic structural models of the L protein that are physically realistic. All computed models have very flexible termini of about 200 amino acids each, and a high proportion of helical regions. Properties such as potential energy, radius of gyration, hydrodynamics radius, flexibility coefficient, and solvent-accessible surface are reported. Structural characterization of the L protein enables our laboratories to better understand viral replication and transcription via further studies of L protein-mediated protein-protein interactions. While results presented a focus on the RVFV L protein, the following workflow is a more general modeling protocol for discovering the tertiary structure of multidomain proteins consisting of thousands of amino acids.
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181
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Dynamical Oligomerisation of Histidine Rich Intrinsically Disordered ProteinS Is Regulated through Zinc-Histidine Interactions. Biomolecules 2019; 9:biom9050168. [PMID: 31052346 PMCID: PMC6571702 DOI: 10.3390/biom9050168] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/26/2019] [Accepted: 04/26/2019] [Indexed: 12/19/2022] Open
Abstract
Intrinsically disordered proteins (IDPs) can form functional oligomers and in some cases, insoluble disease related aggregates. It is therefore vital to understand processes and mechanisms that control pathway distribution. Divalent cations including Zn2+ can initiate IDP oligomerisation through the interaction with histidine residues but the mechanisms of doing so are far from understood. Here we apply a multi-disciplinary approach using small angle X-ray scattering, nuclear magnetic resonance spectroscopy, calorimetry and computations to show that that saliva protein Histatin 5 forms highly dynamic oligomers in the presence of Zn2+. The process is critically dependent upon interaction between Zn2+ ions and distinct histidine rich binding motifs which allows for thermodynamic switching between states. We propose a molecular mechanism of oligomerisation, which may be generally applicable to other histidine rich IDPs. Finally, as Histatin 5 is an important saliva component, we suggest that Zn2+ induced oligomerisation may be crucial for maintaining saliva homeostasis.
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182
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Baul U, Chakraborty D, Mugnai ML, Straub JE, Thirumalai D. Sequence Effects on Size, Shape, and Structural Heterogeneity in Intrinsically Disordered Proteins. J Phys Chem B 2019; 123:3462-3474. [PMID: 30913885 PMCID: PMC6920032 DOI: 10.1021/acs.jpcb.9b02575] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Intrinsically disordered proteins (IDPs) lack well-defined three-dimensional structures, thus challenging the archetypal notion of structure-function relationships. Determining the ensemble of conformations that IDPs explore under physiological conditions is the first step toward understanding their diverse cellular functions. Here, we quantitatively characterize the structural features of IDPs as a function of sequence and length using coarse-grained simulations. For diverse IDP sequences, with the number of residues ( NT) ranging from 20 to 441, our simulations not only reproduce the radii of gyration ( Rg) obtained from experiments, but also predict the full scattering intensity profiles in excellent agreement with small-angle X-ray scattering experiments. The Rg values are well-described by the standard Flory scaling law, Rg = Rg0 NTν, with ν ≈ 0.588, making it tempting to assert that IDPs behave as polymers in a good solvent. However, clustering analysis reveals that the menagerie of structures explored by IDPs is diverse, with the extent of heterogeneity being highly sequence-dependent, even though ensemble-averaged properties, such as the dependence of Rg on chain length, may suggest synthetic polymer-like behavior in a good solvent. For example, we show that for the highly charged Prothymosin-α, a substantial fraction of conformations is highly compact. Even if the sequence compositions are similar, as is the case for α-Synuclein and a truncated construct from the Tau protein, there are substantial differences in the conformational heterogeneity. Taken together, these observations imply that metrics based on net charge or related quantities alone cannot be used to anticipate the phases of IDPs, either in isolation or in complex with partner IDPs or RNA. Our work sets the stage for probing the interactions of IDPs with each other, with folded protein domains, or with partner RNAs, which are critical for describing the structures of stress granules and biomolecular condensates with important cellular functions.
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Affiliation(s)
- Upayan Baul
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Debayan Chakraborty
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Mauro L. Mugnai
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
| | - John E. Straub
- Department of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - D. Thirumalai
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, United States
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183
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Payliss BJ, Vogel J, Mittermaier AK. Side chain electrostatic interactions and pH-dependent expansion of the intrinsically disordered, highly acidic carboxyl-terminus of γ-tubulin. Protein Sci 2019; 28:1095-1105. [PMID: 30968464 DOI: 10.1002/pro.3618] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/04/2019] [Accepted: 04/08/2019] [Indexed: 11/09/2022]
Abstract
Intramolecular electrostatic attraction and repulsion strongly influence the conformational sampling of intrinsically disordered proteins and domains (IDPs). In order to better understand this complex relationship, we have used nuclear magnetic resonance to measure side chain pKa values and pH-dependent translational diffusion coefficients for the unstructured and highly acidic carboxyl-terminus of γ-tubulin (γ-CT), providing insight into how the net charge of an IDP relates to overall expansion or collapse of the conformational ensemble. Many of the pKa values in the γ-CT are shifted upward by 0.3-0.4 units and exhibit negatively cooperative ionization pH profiles, likely due to the large net negative charge that accumulates on the molecule as the pH is raised. pKa shifts of this magnitude correspond to electrostatic interaction energies between the affected residues and the rest of the charged molecule that are each on the order of 1 kcal mol-1 . Diffusion of the γ-CT slowed with increasing net charge, indicative of an expanding hydrodynamic radius (rH ). The degree of expansion agreed quantitatively with what has been seen from comparisons of IDPs with different charge content, yielding the general trend that every 0.1 increase in relative charge (|Q|/res) produces a roughly 5% increase in rH . While γ-CT pH titration data followed this trend nearly perfectly, there were substantially larger deviations for the database of different IDP sequences. This suggests that other aspects of an IDP's primary amino acid sequence beyond net charge influence the sensitivity of rH to electrostatic interactions.
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Affiliation(s)
- Brandon J Payliss
- Department of Chemistry, McGill University, Montreal, Quebec, Canada
| | - Jackie Vogel
- Department of Biology, McGill University, Montreal, Quebec, Canada.,The School of Computer Science, McGill University, Montreal, Quebec, Canada
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184
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Zegarra FC, Homouz D, Gasic AG, Babel L, Kovermann M, Wittung-Stafshede P, Cheung MS. Crowding-Induced Elongated Conformation of Urea-Unfolded Apoazurin: Investigating the Role of Crowder Shape in Silico. J Phys Chem B 2019; 123:3607-3617. [PMID: 30963769 DOI: 10.1021/acs.jpcb.9b00782] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Here, we show by solution nuclear magnetic resonance measurements that the urea-unfolded protein apoazurin becomes elongated when the synthetic crowding agent dextran 20 is present, in contrast to the prediction from the macromolecular crowding effect based on the argument of volume exclusion. To explore the complex interactions beyond volume exclusion, we employed coarse-grained molecular dynamics simulations to explore the conformational ensemble of apoazurin in a box of monodisperse crowders under strong chemically denaturing conditions. The elongated conformation of unfolded apoazurin appears to result from the interplay of the effective attraction between the protein and crowders and the shape of the crowders. With a volume-conserving crowder model, we show that the crowder shape provides an anisotropic direction of the depletion force, in which a bundle of surrounding rodlike crowders stabilize an elongated conformation of unfolded apoazurin in the presence of effective attraction between the protein and crowders.
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Affiliation(s)
- Fabio C Zegarra
- Department of Physics , University of Houston , Houston 77204 , United States
| | - Dirar Homouz
- Department of Physics , University of Houston , Houston 77204 , United States.,Department of Physics , Khalifa University of Science and Technology , Abu Dhabi , UAE.,Center for Theoretical Biological Physics , Rice University , Houston 77005 , United States
| | - Andrei G Gasic
- Department of Physics , University of Houston , Houston 77204 , United States.,Center for Theoretical Biological Physics , Rice University , Houston 77005 , United States
| | - Lucas Babel
- Department of Physics , University of Houston , Houston 77204 , United States
| | | | | | - Margaret S Cheung
- Department of Physics , University of Houston , Houston 77204 , United States.,Center for Theoretical Biological Physics , Rice University , Houston 77005 , United States
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185
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Guckeisen T, Hosseinpour S, Peukert W. Isoelectric Points of Proteins at the Air/Liquid Interface and in Solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:5004-5012. [PMID: 30892047 DOI: 10.1021/acs.langmuir.9b00311] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Electrostatic interactions play essential roles in determining the function, colloidal stability, and adsorption of proteins on different surfaces and interfaces. Therefore, a molecular-level understanding of the charge state of the proteins under different conditions is required to explain their macroscopic properties. In this study, we have employed an inherently surface-sensitive spectroscopic tool, sum frequency generation spectroscopy, to determine the charge state of a wide range of proteins as a function of pH at the air/liquid interface via measurement of the degree of orientation of water molecules. We compared the isoelectric point (IEP) of the 12 investigated proteins at the air/liquid interface with that in the bulk solution obtained through zeta potential measurements. Ellipsometry is performed to determine the film thickness at the air/liquid interface at different charge states. In particular, protein aggregation at the IEP is reflected by increased film thickness. For all proteins, the interfacial point of zero charge is close (with less than 1 pH unit variation) to that in the bulk solution.
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Affiliation(s)
- Tobias Guckeisen
- Institute of Particle Technology (LFG) , Friedrich-Alexander-Universität-Erlangen-Nürnberg (FAU) , Cauerstraße 4 , 91058 Erlangen , Germany
| | - Saman Hosseinpour
- Institute of Particle Technology (LFG) , Friedrich-Alexander-Universität-Erlangen-Nürnberg (FAU) , Cauerstraße 4 , 91058 Erlangen , Germany
| | - Wolfgang Peukert
- Institute of Particle Technology (LFG) , Friedrich-Alexander-Universität-Erlangen-Nürnberg (FAU) , Cauerstraße 4 , 91058 Erlangen , Germany
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186
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Hepatitis B virus X protein induces size-selective membrane permeabilization through interaction with cardiolipin. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:729-737. [DOI: 10.1016/j.bbamem.2019.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 11/25/2018] [Accepted: 01/13/2019] [Indexed: 02/07/2023]
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187
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Jephthah S, Staby L, Kragelund BB, Skepö M. Temperature Dependence of Intrinsically Disordered Proteins in Simulations: What are We Missing? J Chem Theory Comput 2019; 15:2672-2683. [DOI: 10.1021/acs.jctc.8b01281] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S. Jephthah
- Division of Theoretical Chemistry, Lund University, 221 00 Lund, Sweden
| | - L. Staby
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - B. B. Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, DK-2200 Copenhagen, Denmark
| | - M. Skepö
- Division of Theoretical Chemistry, Lund University, 221 00 Lund, Sweden
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188
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Zhang R, Wu H, He M, Zhang W, Xu W. Mobility Capillary Electrophoresis-Restrained Modeling Method for Protein Structure Analysis in Mixtures. J Phys Chem B 2019; 123:2335-2341. [PMID: 30807169 DOI: 10.1021/acs.jpcb.9b01148] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Protein stereostructure analysis in mixtures still remains challenging, especially large-scale analysis such as in proteomics. With the capability of measuring the hydrodynamic radius of ions in the liquid phase, mobility capillary electrophoresis (MCE) has been applied to study the structure of peptides. In this study, MCE was extended for protein mixture separation and their corresponding hydrodynamic radius analyses. After ellipsoid approximation, the results obtained by MCE experiments were then used as a restraint in molecular dynamics simulations to predict the most probable structure of each protein. Besides a three-protein mixture, a mixture of disulfide bond reduced insulin was also studied by this MCE-restrained modeling method. The results obtained by this method agree with literature studies, and mass spectrometry experiments were also carried out to confirm our findings.
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Affiliation(s)
- Rongkai Zhang
- School of Life Science , Beijing Institute of Technology , Beijing 100081 , China
| | - Haimei Wu
- School of Life Science , Beijing Institute of Technology , Beijing 100081 , China
| | - Muyi He
- School of Life Science , Beijing Institute of Technology , Beijing 100081 , China
| | - Wenjing Zhang
- School of Life Science , Beijing Institute of Technology , Beijing 100081 , China
| | - Wei Xu
- School of Life Science , Beijing Institute of Technology , Beijing 100081 , China
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189
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Dudás EF, Bodor A. Quantitative, Diffusion NMR Based Analytical Tool To Distinguish Folded, Disordered, and Denatured Biomolecules. Anal Chem 2019; 91:4929-4933. [DOI: 10.1021/acs.analchem.8b05617] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Erika F. Dudás
- Laboratory of Structural Chemistry and Biology, Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/a, Budapest 1117, Hungary
| | - Andrea Bodor
- Laboratory of Structural Chemistry and Biology, Institute of Chemistry, Eötvös Loránd University, Pázmány Péter sétány 1/a, Budapest 1117, Hungary
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190
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Li X, Dong C, Hoffmann M, Garen CR, Cortez LM, Petersen NO, Woodside MT. Early stages of aggregation of engineered α-synuclein monomers and oligomers in solution. Sci Rep 2019; 9:1734. [PMID: 30741954 PMCID: PMC6370846 DOI: 10.1038/s41598-018-37584-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 12/10/2018] [Indexed: 12/15/2022] Open
Abstract
α-Synuclein is a protein that aggregates as amyloid fibrils in the brains of patients with Parkinson's disease and dementia with Lewy bodies. Small oligomers of α-synuclein are neurotoxic and are thought to be closely associated with disease. Whereas α-synuclein fibrillization and fibril morphologies have been studied extensively with various methods, the earliest stages of aggregation and the properties of oligomeric intermediates are less well understood because few methods are able to detect and characterize early-stage aggregates. We used fluorescence spectroscopy to investigate the early stages of aggregation by studying pairwise interactions between α-synuclein monomers, as well as between engineered tandem oligomers of various sizes (dimers, tetramers, and octamers). The hydrodynamic radii of these engineered α-synuclein species were first determined by fluorescence correlation spectroscopy and dynamic light scattering. The rate of pairwise aggregation between different species was then monitored using dual-color fluorescence cross-correlation spectroscopy, measuring the extent of association between species labelled with different dyes at various time points during the early aggregation process. The aggregation rate and extent increased with tandem oligomer size. Self-association of the tandem oligomers was found to be the preferred pathway to form larger aggregates: interactions between oligomers occurred faster and to a greater extent than interactions between oligomers and monomers, indicating that the oligomers were not as efficient in seeding further aggregation by addition of monomers. These results suggest that oligomer-oligomer interactions may play an important role in driving aggregation during its early stages.
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Affiliation(s)
- Xi Li
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada.,Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Chunhua Dong
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada.,Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Marion Hoffmann
- Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Craig R Garen
- Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada
| | - Leonardo M Cortez
- Division of Neurology, Department of Medicine, Centre for Prions and Protein Folding Diseases, and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, T6G 2M8, Canada
| | - Nils O Petersen
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada.
| | - Michael T Woodside
- Department of Physics, University of Alberta, Edmonton, AB, T6G 2E1, Canada.
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191
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Arrabal-Campos FM, Aguilera-Sáez LM, Fernández I. Algebraic Reconstruction Technique for Diffusion NMR Experiments. Application to the Molecular Weight Prediction of Polymers. J Phys Chem A 2019; 123:943-950. [DOI: 10.1021/acs.jpca.8b08584] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Francisco M. Arrabal-Campos
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, Universidad de Almería, Ctra. Sacramento, s/n, Almería, E-04120, Spain
| | - Luis M. Aguilera-Sáez
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, Universidad de Almería, Ctra. Sacramento, s/n, Almería, E-04120, Spain
| | - Ignacio Fernández
- Department of Chemistry and Physics, Research Centre CIAIMBITAL, Universidad de Almería, Ctra. Sacramento, s/n, Almería, E-04120, Spain
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192
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Kukuk L, Dingley AJ, Granzin J, Nagel-Steger L, Thiagarajan-Rosenkranz P, Ciupka D, Hänel K, Batra-Safferling R, Pacheco V, Stoldt M, Pfeffer K, Beer-Hammer S, Willbold D, Koenig BW. Structure of the SLy1 SAM homodimer reveals a new interface for SAM domain self-association. Sci Rep 2019; 9:54. [PMID: 30631134 PMCID: PMC6328559 DOI: 10.1038/s41598-018-37185-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 11/30/2018] [Indexed: 11/08/2022] Open
Abstract
Sterile alpha motif (SAM) domains are protein interaction modules that are involved in a diverse range of biological functions such as transcriptional and translational regulation, cellular signalling, and regulation of developmental processes. SH3 domain-containing protein expressed in lymphocytes 1 (SLy1) is involved in immune regulation and contains a SAM domain of unknown function. In this report, the structure of the SLy1 SAM domain was solved and revealed that this SAM domain forms a symmetric homodimer through a novel interface. The interface consists primarily of the two long C-terminal helices, α5 and α5', of the domains packing against each other. The dimerization is characterized by a dissociation constant in the lower micromolar range. A SLy1 SAM domain construct with an extended N-terminus containing five additional amino acids of the SLy1 sequence further increases the stability of the homodimer, making the SLy1 SAM dimer two orders of magnitude more stable than previously studied SAM homodimers, suggesting that the SLy1 SAM dimerization is of functional significance. The SLy1 SAM homodimer contains an exposed mid-loop surface on each monomer, which may provide a scaffold for mediating interactions with other SAM domain-containing proteins via a typical mid-loop-end-helix interface.
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Affiliation(s)
- Laura Kukuk
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Andrew J Dingley
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Joachim Granzin
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Luitgard Nagel-Steger
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Pallavi Thiagarajan-Rosenkranz
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Daniel Ciupka
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Karen Hänel
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Renu Batra-Safferling
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
| | - Victor Pacheco
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany
- Institut für Makromolekulare Chemie, Albert-Ludwigs-Universität Freiburg, Stefan-Meier-Straße 31, 79104, Freiburg, Germany
| | - Matthias Stoldt
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Klaus Pfeffer
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Sandra Beer-Hammer
- Institut für Medizinische Mikrobiologie und Krankenhaushygiene, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, und Interfakultäres Zentrum für Pharmakogenomik und Arzneimittelforschung (ICePhA), Eberhard-Karls-Universität Tübingen, Wilhelmstraße 56, 72074, Tübingen, Germany
| | - Dieter Willbold
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany.
| | - Bernd W Koenig
- Institute of Complex Systems, Strukturbiochemie (ICS-6), Forschungszentrum Jülich, 52425, Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany.
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193
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Carver JA, Holt C. Functional and dysfunctional folding, association and aggregation of caseins. PROTEIN MISFOLDING 2019; 118:163-216. [DOI: 10.1016/bs.apcsb.2019.09.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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194
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Design and structural characterisation of monomeric water-soluble α-helix and β-hairpin peptides: State-of-the-art. Arch Biochem Biophys 2019; 661:149-167. [DOI: 10.1016/j.abb.2018.11.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 11/06/2018] [Accepted: 11/14/2018] [Indexed: 02/06/2023]
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195
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Kunihara T, Hayashi Y, Arai M. Conformational diversity in the intrinsically disordered HIV-1 Tat protein induced by zinc and pH. Biochem Biophys Res Commun 2018; 509:564-569. [PMID: 30600181 DOI: 10.1016/j.bbrc.2018.12.126] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 12/15/2018] [Accepted: 12/17/2018] [Indexed: 11/30/2022]
Abstract
Human immunodeficiency virus type-1 (HIV-1) transactivator of transcription (Tat) is an intrinsically disordered protein that exerts multiple functions, including activation of HIV-1 replication and induction of T-cell apoptosis and cytokine secretion via zinc binding and cellular uptake by endocytosis. However, the effects of zinc and endosomal low pH on the structure of isolated Tat protein are poorly understood. Here, we purified a monomeric zinc-bound Tat and studied its structure and acid denaturation by circular dichroism, NMR, and small-angle X-ray scattering. We found that at pH 7, the zinc-bound Tat was in a pre-molten globule state; it exhibited largely disordered conformations with residual helices and was slightly more compact than the fully unfolded states that were observed at pH 4 or in the zinc-free form. Moreover, acid-induced unfolding transitions in secondary structure and molecular size occurred at different pH ranges, indicating the presence of an expanded and helical intermediate at pH ∼6. Taken together, the extent of structural disorder in the intrinsically disordered Tat protein is highly sensitive to zinc and pH, suggesting that zinc binding and pH affect Tat structures and thereby control the versatile functions of Tat.
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Affiliation(s)
- Tomoko Kunihara
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan
| | - Yuuki Hayashi
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan
| | - Munehito Arai
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan; Department of Physics, Graduate School of Science, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan.
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196
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Yuwen T, Sekhar A, Baldwin AJ, Vallurupalli P, Kay LE. Measuring Diffusion Constants of Invisible Protein Conformers by Triple‐Quantum
1
H CPMG Relaxation Dispersion. Angew Chem Int Ed Engl 2018; 57:16777-16780. [DOI: 10.1002/anie.201810868] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Indexed: 11/11/2022]
Affiliation(s)
- Tairan Yuwen
- Departments of Molecular Genetics, Biochemistry and ChemistryUniversity of Toronto Toronto Ontario M5S 1A8 Canada
| | - Ashok Sekhar
- Molecular Biophysics UnitIndian Institute of Science Bangalore Karnataka 560012 India
| | - Andrew J. Baldwin
- Physical and Theoretical Chemistry LaboratoryUniversity of Oxford Oxford OX1 3QZ UK
| | - Pramodh Vallurupalli
- TIFR Centre for Interdisciplinary SciencesTata Institute of Fundamental Research Hyderabad Telangana 500107 India
| | - Lewis E. Kay
- Departments of Molecular Genetics, Biochemistry and ChemistryUniversity of Toronto Toronto Ontario M5S 1A8 Canada
- Program in Molecular MedicineHospital for Sick Children 555 University Avenue Toronto Ontario M5G 1X8 Canada
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197
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Yuwen T, Sekhar A, Baldwin AJ, Vallurupalli P, Kay LE. Measuring Diffusion Constants of Invisible Protein Conformers by Triple‐Quantum
1
H CPMG Relaxation Dispersion. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201810868] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Tairan Yuwen
- Departments of Molecular Genetics, Biochemistry and ChemistryUniversity of Toronto Toronto Ontario M5S 1A8 Canada
| | - Ashok Sekhar
- Molecular Biophysics UnitIndian Institute of Science Bangalore Karnataka 560012 India
| | - Andrew J. Baldwin
- Physical and Theoretical Chemistry LaboratoryUniversity of Oxford Oxford OX1 3QZ UK
| | - Pramodh Vallurupalli
- TIFR Centre for Interdisciplinary SciencesTata Institute of Fundamental Research Hyderabad Telangana 500107 India
| | - Lewis E. Kay
- Departments of Molecular Genetics, Biochemistry and ChemistryUniversity of Toronto Toronto Ontario M5S 1A8 Canada
- Program in Molecular MedicineHospital for Sick Children 555 University Avenue Toronto Ontario M5G 1X8 Canada
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198
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Kenri T, Kawakita Y, Kudo H, Matsumoto U, Mori S, Furukawa Y, Tahara YO, Shibayama K, Hayashi Y, Arai M, Miyata M. Production and characterization of recombinant P1 adhesin essential for adhesion, gliding, and antigenic variation in the human pathogenic bacterium, Mycoplasma pneumoniae. Biochem Biophys Res Commun 2018; 508:1050-1055. [PMID: 30551878 DOI: 10.1016/j.bbrc.2018.11.132] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 11/05/2018] [Accepted: 11/20/2018] [Indexed: 10/27/2022]
Abstract
Mycoplasma pneumoniae forms an attachment organelle at one cell pole, binds to the host cell surface, and glides via a unique mechanism. A 170-kDa protein, P1 adhesin, present on the organelle surface plays a critical role in the binding and gliding process. In this study, we obtained a recombinant P1 adhesin comprising 1476 amino acid residues, excluding the C-terminal domain of 109 amino acids that carried the transmembrane segment, that were fused to additional 17 amino acid residues carrying a hexa-histidine (6 × His) tag using an Escherichia coli expression system. The recombinant protein showed solubility, and chirality in circular dichroism (CD). The results of analytical gel filtration, ultracentrifugation, negative-staining electron microscopy, and small-angle X-ray scattering (SAXS) showed that the recombinant protein exists in a monomeric form with a uniformly folded structure. SAXS analysis suggested the presence of a compact and ellipsoidal structure rather than random or molten globule-like conformation. Structure model based on SAXS results fitted well with the corresponding structure obtained with cryo-electron tomography from a closely related species, M. genitalium. This recombinant protein may be useful for structural and functional studies as well as for the preparation of antibodies for medical applications.
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Affiliation(s)
- Tsuyoshi Kenri
- Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo, 208-0011, Japan
| | - Yoshito Kawakita
- Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Hisashi Kudo
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan
| | - U Matsumoto
- Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan
| | - Shigetarou Mori
- Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo, 208-0011, Japan
| | - Yukio Furukawa
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Yuhei O Tahara
- Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan; The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Osaka, Japan
| | - Keigo Shibayama
- Department of Bacteriology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama, Tokyo, 208-0011, Japan
| | - Yuuki Hayashi
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan
| | - Munehito Arai
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan; Department of Physics, Graduate School of Science, The University of Tokyo, 3-8-1 Komaba, Meguro, Tokyo, 153-8902, Japan
| | - Makoto Miyata
- Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan; The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Osaka, Japan.
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Möckel C, Kubiak J, Schillinger O, Kühnemuth R, Della Corte D, Schröder GF, Willbold D, Strodel B, Seidel CAM, Neudecker P. Integrated NMR, Fluorescence, and Molecular Dynamics Benchmark Study of Protein Mechanics and Hydrodynamics. J Phys Chem B 2018; 123:1453-1480. [DOI: 10.1021/acs.jpcb.8b08903] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Christina Möckel
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Jakub Kubiak
- Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Oliver Schillinger
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Theoretische Chemie und Computerchemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Ralf Kühnemuth
- Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Dennis Della Corte
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Gunnar F. Schröder
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
- Physics Department, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Dieter Willbold
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Birgit Strodel
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Theoretische Chemie und Computerchemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Claus A. M. Seidel
- Lehrstuhl für Molekulare Physikalische Chemie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Philipp Neudecker
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Complex Systems (ICS-6: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany
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The C Terminus of the Ribosomal-Associated Protein LrtA Is an Intrinsically Disordered Oligomer. Int J Mol Sci 2018; 19:ijms19123902. [PMID: 30563168 PMCID: PMC6321479 DOI: 10.3390/ijms19123902] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 11/28/2018] [Accepted: 12/02/2018] [Indexed: 01/01/2023] Open
Abstract
The 191-residue-long LrtA protein of Synechocystis sp. PCC 6803 is involved in post-stress survival and in stabilizing 70S ribosomal particles. It belongs to the hibernating promoting factor (HPF) family, intervening in protein synthesis. The protein consists of two domains: The N-terminal region (N-LrtA, residues 1–101), which is common to all the members of the HPF, and seems to be well-folded; and the C-terminal region (C-LrtA, residues 102–191), which is hypothesized to be disordered. In this work, we studied the conformational preferences of isolated C-LrtA in solution. The protein was disordered, as shown by computational modelling, 1D-1H NMR, steady-state far-UV circular dichroism (CD) and chemical and thermal denaturations followed by fluorescence and far-UV CD. Moreover, at physiological conditions, as indicated by several biochemical and hydrodynamic techniques, isolated C-LrtA intervened in a self-association equilibrium, involving several oligomerization reactions. Thus, C-LrtA was an oligomeric disordered protein.
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