1
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Gao K, Rao J, Chen B. Plant protein solubility: A challenge or insurmountable obstacle. Adv Colloid Interface Sci 2024; 324:103074. [PMID: 38181662 DOI: 10.1016/j.cis.2023.103074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/26/2023] [Accepted: 12/22/2023] [Indexed: 01/07/2024]
Abstract
Currently, there is an increasing focus on comprehending the solubility of plant-based proteins, driven by the rising demand for animal-free food formulations. The solubility of proteins plays a crucial role in impacting other functional properties of proteins and food processing. Consequently, understanding protein solubility in a deeper sense may allow a better usage of plant proteins. Herein, we discussed the definition of protein solubility from both thermodynamic and colloidal perspectives. A range of factors affecting solubility of plant proteins are generalized, including intrinsic factors (amino acids composition, hydrophobicity), and extrinsic factors (pH, ionic strength, extraction and drying methods). Current methods to enhance solubility are outlined, including microwave, high intensity ultrasound, hydrostatic pressure, glycation, pH-shifting, enzymatic hydrolysis, enzymatic cross-linking, complexation and modulation of amino acids. We base the discussion on diverse modified methods of nitrogen solubility index available to determine and analyze protein solubility followed by addressing how other indigenous components affect the solubility of plant proteins. Some nonproteinaceous constituents in proteins such as carbohydrates and polyphenols may exert positive or negative impact on protein solubility. Appropriate protein extraction and modification methods that meet consumer and manufacturers requirements concerning nutritious and eco-friendly foods with lower cost should be investigated and further explored.
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Affiliation(s)
- Kun Gao
- Department of Plant Sciences, North Dakota State University, Fargo, ND 58108, USA
| | - Jiajia Rao
- Department of Plant Sciences, North Dakota State University, Fargo, ND 58108, USA
| | - Bingcan Chen
- Department of Plant Sciences, North Dakota State University, Fargo, ND 58108, USA.
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2
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Martínez-Rodríguez S, Cámara-Artigas A, Gavira JA. First 3-D structural evidence of a native-like intertwined dimer in the acylphosphatase family. Biochem Biophys Res Commun 2023; 682:85-90. [PMID: 37804591 DOI: 10.1016/j.bbrc.2023.09.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 09/20/2023] [Indexed: 10/09/2023]
Abstract
Acylphosphatase (AcP, EC 3.6.1.7) is a small model protein conformed by a ferredoxin-like fold, profoundly studied to get insights into protein folding and aggregation processes. Numerous studies focused on the aggregation and/or amyloidogenic properties of AcPs suggest the importance of edge-β-strands in the process. In this work, we present the first crystallographic structure of Escherichia coli AcP (EcoAcP), showing notable differences with the only available NMR structure for this enzyme. EcoAcP is crystalised as an intertwined dimer formed by replacing a single C-terminal β-strand between two protomers, suggesting a flexible character of the C-terminal edge of EcoAcP. Despite numerous works where AcP from different sources have been used as a model system for protein aggregation, our domain-swapped EcoAcP structure is the first 3-D structural evidence of native-like aggregated species for any AcP reported to date, providing clues on molecular determinants unleashing aggregation.
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Affiliation(s)
- Sergio Martínez-Rodríguez
- Department of Biochemistry and Molecular Biology III and Immunology, University of Granada, Avenida de La Investigación 11, Granada, 18071, Spain; Laboratorio de Estudios Cristalográficos, CSIC-UGR, Avda. de Las Palmeras 4, Armilla, Granada, 18100, Spain.
| | - Ana Cámara-Artigas
- Department of Chemistry and Physics, University of Almería, Agrifood Campus of International Excellence (ceiA3), Centro de Investigación en Agrosistemas Intensivos Mediterráneos y Biotecnología Agroalimentaria (CIAMBITAL), Carretera de Sacramento S/n, Almería, 04120, Spain
| | - Jose Antonio Gavira
- Laboratorio de Estudios Cristalográficos, CSIC-UGR, Avda. de Las Palmeras 4, Armilla, Granada, 18100, Spain
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3
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Gonzalez-Garcia M, Fusco G, De Simone A. Metal interactions of α-synuclein probed by NMR amide-proton exchange. Front Chem 2023; 11:1167766. [PMID: 37201129 PMCID: PMC10187754 DOI: 10.3389/fchem.2023.1167766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 04/07/2023] [Indexed: 05/20/2023] Open
Abstract
The aberrant aggregation of α-synuclein (αS), a disordered protein primarily expressed in neuronal cells, is strongly associated with the underlying mechanisms of Parkinson's disease. It is now established that αS has a weak affinity for metal ions and that these interactions alter its conformational properties by generally promoting self-assembly into amyloids. Here, we characterised the nature of the conformational changes associated with metal binding by αS using nuclear magnetic resonance (NMR) to measure the exchange of the backbone amide protons at a residue specific resolution. We complemented these experiments with 15N relaxation and chemical shift perturbations to obtain a comprehensive map of the interaction between αS and divalent (Ca2+, Cu2+, Mn2+, and Zn2+) and monovalent (Cu+) metal ions. The data identified specific effects that the individual cations exert on the conformational properties of αS. In particular, binding to calcium and zinc generated a reduction of the protection factors in the C-terminal region of the protein, whereas both Cu(II) and Cu(I) did not alter the amide proton exchange along the αS sequence. Changes in the R2/R1 ratios from 15N relaxation experiments were, however, detected as a result of the interaction between αS and Cu+ or Zn2+, indicating that binding to these metals induces conformational perturbations in distinctive regions of the protein. Collectively our data suggest that multiple mechanisms of enhanced αS aggregation are associated with the binding of the analysed metals.
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Affiliation(s)
| | - Giuliana Fusco
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
- *Correspondence: Alfonso De Simone, ; Giuliana Fusco,
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, London, United Kingdom
- Department of Pharmacy, University of Naples “Federico II”, Naples, Italy
- *Correspondence: Alfonso De Simone, ; Giuliana Fusco,
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4
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Fusco G, Bemporad F, Chiti F, Dobson CM, De Simone A. The role of structural dynamics in the thermal adaptation of hyperthermophilic enzymes. Front Mol Biosci 2022; 9:981312. [PMID: 36158582 PMCID: PMC9490001 DOI: 10.3389/fmolb.2022.981312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 08/09/2022] [Indexed: 11/13/2022] Open
Abstract
Proteins from hyperthermophilic organisms are evolutionary optimised to adopt functional structures and dynamics under conditions in which their mesophilic homologues are generally inactive or unfolded. Understanding the nature of such adaptation is of crucial interest to clarify the underlying mechanisms of biological activity in proteins. Here we measured NMR residual dipolar couplings of a hyperthermophilic acylphosphatase enzyme at 80°C and used these data to generate an accurate structural ensemble representative of its native state. The resulting energy landscape was compared to that obtained for a human homologue at 37°C, and additional NMR experiments were carried out to probe fast (15N relaxation) and slow (H/D exchange) backbone dynamics, collectively sampling fluctuations of the two proteins ranging from the nanosecond to the millisecond timescale. The results identified key differences in the strategies for protein-protein and protein-ligand interactions of the two enzymes at the respective physiological temperatures. These include the dynamical behaviour of a β-strand involved in the protection against aberrant protein aggregation and concerted motions of loops involved in substrate binding and catalysis. Taken together these results elucidate the structure-dynamics-function relationship associated with the strategies of thermal adaptation of protein molecules.
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Affiliation(s)
- Giuliana Fusco
- Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
| | - Francesco Bemporad
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | | | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, London, United Kingdom
- Department of Pharmacy, University of Naples “Federico II”, Naples, Italy
- *Correspondence: Alfonso De Simone,
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5
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Errico S, Ramshini H, Capitini C, Canale C, Spaziano M, Barbut D, Calamai M, Zasloff M, Oropesa-Nuñez R, Vendruscolo M, Chiti F. Quantitative Measurement of the Affinity of Toxic and Nontoxic Misfolded Protein Oligomers for Lipid Bilayers and of its Modulation by Lipid Composition and Trodusquemine. ACS Chem Neurosci 2021; 12:3189-3202. [PMID: 34382791 PMCID: PMC8414483 DOI: 10.1021/acschemneuro.1c00327] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 07/29/2021] [Indexed: 12/13/2022] Open
Abstract
Many neurodegenerative diseases are associated with the self-assembly of peptides and proteins into fibrillar aggregates. Soluble misfolded oligomers formed during the aggregation process, or released by mature fibrils, play a relevant role in neurodegenerative processes through their interactions with neuronal membranes. However, the determinants of the cytotoxicity of these oligomers are still unclear. Here we used liposomes and toxic and nontoxic oligomers formed by the same protein to measure quantitatively the affinity of the two oligomeric species for lipid membranes. To this aim, we quantified the perturbation to the lipid membranes caused by the two oligomers by using the fluorescence quenching of two probes embedded in the polar and apolar regions of the lipid membranes and a well-defined protein-oligomer binding assay using fluorescently labeled oligomers to determine the Stern-Volmer and dissociation constants, respectively. With both approaches, we found that the toxic oligomers have a membrane affinity 20-25 times higher than that of nontoxic oligomers. Circular dichroism, intrinsic fluorescence, and FRET indicated that neither oligomer type changes its structure upon membrane interaction. Using liposomes enriched with trodusquemine, a potential small molecule drug known to penetrate lipid membranes and make them refractory to toxic oligomers, we found that the membrane affinity of the oligomers was remarkably lower. At protective concentrations of the small molecule, the binding of the oligomers to the lipid membranes was fully prevented. Furthermore, the affinity of the toxic oligomers for the lipid membranes was found to increase and slightly decrease with GM1 ganglioside and cholesterol content, respectively, indicating that physicochemical properties of lipid membranes modulate their affinity for misfolded oligomeric species.
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Affiliation(s)
- Silvia Errico
- Department
of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence 50134, Italy
- Centre
for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Hassan Ramshini
- Department
of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence 50134, Italy
- Department
of Biology, Payame Noor University, Tehran 19395-4697, Islamic Republic of Iran
| | - Claudia Capitini
- European
Laboratory for Non-linear Spectroscopy (LENS), Sesto Fiorentino 50019, Italy
- Department
of Physics and Astronomy, University of
Florence, Sesto
Fiorentino 50019, Italy
| | - Claudio Canale
- Department
of Physics, University of Genoa, Genoa 16146, Italy
| | - Martina Spaziano
- Department
of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence 50134, Italy
| | - Denise Barbut
- Enterin
Inc., 2005 Market Street, Philadelphia, Pennsylvania 19103, United States
| | - Martino Calamai
- European
Laboratory for Non-linear Spectroscopy (LENS), Sesto Fiorentino 50019, Italy
- National
Institute of Optics, National Research Council
of Italy (CNR), Florence 50125, Italy
| | - Michael Zasloff
- Enterin
Inc., 2005 Market Street, Philadelphia, Pennsylvania 19103, United States
- MedStar-Georgetown
Transplant Institute, Georgetown University
School of Medicine, Washington D.C. 20007, United States
| | - Reinier Oropesa-Nuñez
- Department
of Materials Science and Engineering, Uppsala
University, Uppsala SE-751 03, Sweden
| | - Michele Vendruscolo
- Centre
for Misfolding Diseases, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Fabrizio Chiti
- Department
of Experimental and Clinical Biomedical Sciences, Section of Biochemistry, University of Florence, Florence 50134, Italy
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6
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Sirangelo I, Iannuzzi C. Understanding the Role of Protein Glycation in the Amyloid Aggregation Process. Int J Mol Sci 2021; 22:ijms22126609. [PMID: 34205510 PMCID: PMC8235188 DOI: 10.3390/ijms22126609] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 02/06/2023] Open
Abstract
Protein function and flexibility is directly related to the native distribution of its structural elements and any alteration in protein architecture leads to several abnormalities and accumulation of misfolded proteins. This phenomenon is associated with a range of increasingly common human disorders, including Alzheimer and Parkinson diseases, type II diabetes, and a number of systemic amyloidosis characterized by the accumulation of amyloid aggregates both in the extracellular space of tissues and as intracellular deposits. Post-translational modifications are known to have an active role in the in vivo amyloid aggregation as able to affect protein structure and dynamics. Among them, a key role seems to be played by non-enzymatic glycation, the most unwanted irreversible modification of the protein structure, which strongly affects long-living proteins throughout the body. This study provided an overview of the molecular effects induced by glycation on the amyloid aggregation process of several protein models associated with misfolding diseases. In particular, we analyzed the role of glycation on protein folding, kinetics of amyloid formation, and amyloid cytotoxicity in order to shed light on the role of this post-translational modification in the in vivo amyloid aggregation process.
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7
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Banach M, Stapor K, Fabian P, Konieczny L, Roterman I. Divergence Entropy-Based Evaluation of Hydrophobic Core in Aggressive and Resistant Forms of Transthyretin. Entropy (Basel) 2021; 23:458. [PMID: 33924717 DOI: 10.3390/e23040458] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/01/2021] [Accepted: 04/09/2021] [Indexed: 12/19/2022]
Abstract
The two forms of transthyretin differing slightly in the tertiary structure, despite the presence of five mutations, show radically different properties in terms of susceptibility to the amyloid transformation process. These two forms of transthyretin are the object of analysis. The search for the sources of these differences was carried out by means of a comparative analysis of the structure of these molecules in their native and early intermediate stage forms in the folding process. The criterion for assessing the degree of similarity and differences is the status of the hydrophobic core. The comparison of the level of arrangement of the hydrophobic core and its initial stages is possible thanks to the application of divergence entropy for the early intermediate stage and for the final forms. It was shown that the minimal differences observed in the structure of the hydrophobic core of the forms available in PDB, turned out to be significantly different in the early stage (ES) structure in folding process. The determined values of divergence entropy for both ES forms indicate the presence of the seed of hydrophobic core only in the form resistant to amyloid transformation. In the form of aggressively undergoing amyloid transformation, the structure lacking such a seed is revealed, being a stretched one with a high content of β-type structure. In the discussed case, the active presence of water in the structural transformation of proteins expressed in the fuzzy oil drop model (FOD) is of decisive importance for the generation of the final protein structure. It has been shown that the resistant form tends to generate a centric hydrophobic core with the possibility of creating a globular structure, i.e., a spherical micelle-like form. The aggressively transforming form reveals in the structure of its early intermediate, a tendency to form the ribbon-like micelle as observed in amyloid.
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8
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Chen J, Zheng S, Zhao H, Yang Y. Structure-aware protein solubility prediction from sequence through graph convolutional network and predicted contact map. J Cheminform 2021; 13:7. [PMID: 33557952 PMCID: PMC7869490 DOI: 10.1186/s13321-021-00488-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 01/20/2021] [Indexed: 11/26/2022] Open
Abstract
Protein solubility is significant in producing new soluble proteins that can reduce the cost of biocatalysts or therapeutic agents. Therefore, a computational model is highly desired to accurately predict protein solubility from the amino acid sequence. Many methods have been developed, but they are mostly based on the one-dimensional embedding of amino acids that is limited to catch spatially structural information. In this study, we have developed a new structure-aware method GraphSol to predict protein solubility by attentive graph convolutional network (GCN), where the protein topology attribute graph was constructed through predicted contact maps only from the sequence. GraphSol was shown to substantially outperform other sequence-based methods. The model was proven to be stable by consistent [Formula: see text] of 0.48 in both the cross-validation and independent test of the eSOL dataset. To our best knowledge, this is the first study to utilize the GCN for sequence-based protein solubility predictions. More importantly, this architecture could be easily extended to other protein prediction tasks requiring a raw protein sequence.
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Affiliation(s)
- Jianwen Chen
- School of Data and Computer Science, Sun Yat-Sen University, Guangzhou, China
| | - Shuangjia Zheng
- School of Data and Computer Science, Sun Yat-Sen University, Guangzhou, China
| | - Huiying Zhao
- Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Yuedong Yang
- School of Data and Computer Science, Sun Yat-Sen University, Guangzhou, China.
- Key Laboratory of Machine Intelligence and Advanced Computing (Sun Yat-Sen University), Guangzhou, 510000, China.
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9
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Rezvani Boroujeni E, Hosseini SM, Fani G, Cecchi C, Chiti F. Soluble Prion Peptide 107-120 Protects Neuroblastoma SH-SY5Y Cells against Oligomers Associated with Alzheimer's Disease. Int J Mol Sci 2020; 21:E7273. [PMID: 33019683 PMCID: PMC7582777 DOI: 10.3390/ijms21197273] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 09/27/2020] [Accepted: 09/28/2020] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is the most prevalent form of dementia and soluble amyloid β (Aβ) oligomers are thought to play a critical role in AD pathogenesis. Cellular prion protein (PrPC) is a high-affinity receptor for Aβ oligomers and mediates some of their toxic effects. The N-terminal region of PrPC can interact with Aβ, particularly the region encompassing residues 95-110. In this study, we identified a soluble and unstructured prion-derived peptide (PrP107-120) that is external to this region of the sequence and was found to successfully reduce the mitochondrial impairment, intracellular ROS generation and cytosolic Ca2+ uptake induced by oligomeric Aβ42 ADDLs in neuroblastoma SH-SY5Y cells. PrP107-120 was also found to rescue SH-SY5Y cells from Aβ42 ADDL internalization. The peptide did not change the structure and aggregation pathway of Aβ42 ADDLs, did not show co-localization with Aβ42 ADDLs in the cells and showed a partial colocalization with the endogenous cellular PrPC. As a sequence region that is not involved in Aβ binding but in PrP self-recognition, the peptide was suggested to protect against the toxicity of Aβ42 oligomers by interfering with cellular PrPC and/or activating a signaling that protected the cells. These results strongly suggest that PrP107-120 has therapeutic potential for AD.
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Affiliation(s)
- Elham Rezvani Boroujeni
- Department of Microbiology and Microbial Biotechnology, Faculty of Life Science and Biotechnology, Shahid Beheshti University, Tehran 1983969411, Iran;
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale G.B Morgagni 50, 50134 Florence, Italy; (G.F.); (C.C.)
| | - Seyed Masoud Hosseini
- Department of Microbiology and Microbial Biotechnology, Faculty of Life Science and Biotechnology, Shahid Beheshti University, Tehran 1983969411, Iran;
| | - Giulia Fani
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale G.B Morgagni 50, 50134 Florence, Italy; (G.F.); (C.C.)
| | - Cristina Cecchi
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale G.B Morgagni 50, 50134 Florence, Italy; (G.F.); (C.C.)
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale G.B Morgagni 50, 50134 Florence, Italy; (G.F.); (C.C.)
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10
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Fabian P, Banach M, Stapor K, Konieczny L, Ptak-Kaczor M, Roterman I. The Structure of Amyloid Versus the Structure of Globular Proteins. Int J Mol Sci 2020; 21:E4683. [PMID: 32630137 DOI: 10.3390/ijms21134683] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 06/21/2020] [Accepted: 06/27/2020] [Indexed: 12/19/2022] Open
Abstract
The issue of changing the structure of globular proteins into an amyloid form is in the focus of researchers' attention. Numerous experimental studies are carried out, and mathematical models to define the essence of amyloid transformation are sought. The present work focuses on the issue of the hydrophobic core structure in amyloids. The form of ordering the hydrophobic core in globular proteins is described by a 3D Gaussian distribution analog to the distribution of hydrophobicity in a spherical micelle. Amyloid fibril is a ribbon-like micelle made up of numerous individual chains, each representing a flat structure. The distribution of hydrophobicity within a single chain included in the fibril describes the 2D Gaussian distribution. Such a description expresses the location of polar residues on a circle with a center with a high level of hydrophobicity. The presence of this type of order in the amyloid forms available in Preotin Data Bank (PDB) (both in proto- and superfibrils) is demonstrated in the present work. In this system, it can be assumed that the amyloid transformation is a chain transition from 3D Gauss ordering to 2D Gauss ordering. This means changing the globular structure to a ribbon-like structure. This observation can provide a simple mathematical model for simulating the amyloid transformation of proteins.
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11
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Banach M, Fabian P, Stapor K, Konieczny L, Ptak-kaczor M, Roterman I. The Status of Edge Strands in Ferredoxin-Like Fold. Symmetry (Basel) 2020; 12:1032. [DOI: 10.3390/sym12061032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
There is an opinion in professional literature that edge-strands in β-sheet are critical to the processes of amyloid transformation. Propagation of fibrillar forms mainly takes place on the basis of β-sheet type interactions. In many proteins, the edge strands represent only a partially matched form to the β-sheet. Therefore, the edge-strand takes slightly distorted forms. The assessment of the level of arrangement can be carried out based on studying the secondary structure as well as the structure of the hydrophobic core. For this purpose, a fuzzy oil drop model was used to determine the contribution of each fragment with a specific secondary structure to the construction of the system being the effect of a certain synergy, which results in the construction of a hydrophobic core. Studying the participation of β-sheets edge fragments in the hydrophobic core construction is the subject of the current analysis. Statuses of these edge fragments in β-sheets in ferredoxin-like folds are treated as factors that disturb the symmetry of the system.
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12
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Abstract
We propose a phosphodiesterase assay based on 1D 1H NMR to monitor the hydrolysis of cyclic nucleotides directly, without requiring tags or the addition of exogenous reagents. The method is suitable to measure phosphodiesterase KM and kcat parameters and to identify phosphodiesterase inhibitors.
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Affiliation(s)
- Madoka Akimoto
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Canada.
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13
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Tompa DR, Kadhirvel S. Changes in hydrophobicity mainly promotes the aggregation tendency of ALS associated SOD1 mutants. Int J Biol Macromol 2020; 145:904-13. [PMID: 31669277 DOI: 10.1016/j.ijbiomac.2019.09.181] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 09/24/2019] [Accepted: 09/26/2019] [Indexed: 12/19/2022]
Abstract
Protein misfolding and aggregation due to mutations, are associated with fatal neurodegenerative disorders. The mutations in Cu/Zn superoxide dismutase (SOD1) causing its misfolding and aggregation are found linked to the motor neuron disorder, amyotrophic lateral sclerosis. Since the mutations are scattered throughout SOD1 structure, determining the exact molecular mechanism underlying the ALS pathology remains unresolved. In this study, we have investigated the major molecular factors that mainly contribute to SOD1 destabilization, intrinsic disorder, and misfolding using sequence and structural information. We have analysed 153 ALS causing SOD1 point mutants for aggregation tendency using four different aggregation prediction tools, viz., Aggrescan3D (A3D), CamSol, GAP and Zyggregator. Our results suggest that 74-79 mutants are susceptible to aggregation, due to distorted native interactions originated at the mutation site. Majority of the aggregation prone mutants are located in the buried regions of SOD1 molecule. Further, the mutations at the hydrophobic amino acids primarily promote the aggregation tendency of SOD1 protein through different destabilizing mechanisms including changes in hydrophobic free energy, loss of electrostatic interactions in the protein's surface and loss of hydrogen bonds that bridges the protein core and surface.
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14
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Donnarumma F, Leone S, Delfi M, Emendato A, Ami D, Laurents DV, Natalello A, Spadaccini R, Picone D. Probing structural changes during amyloid aggregation of the sweet protein MNEI. FEBS J 2019; 287:2808-2822. [DOI: 10.1111/febs.15168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/20/2019] [Accepted: 12/05/2019] [Indexed: 12/13/2022]
Affiliation(s)
- Federica Donnarumma
- Department of Chemical Sciences University of Naples ‘Federico II’ Napoli Italy
| | - Serena Leone
- Department of Chemical Sciences University of Naples ‘Federico II’ Napoli Italy
| | - Masoud Delfi
- Department of Chemical Sciences University of Naples ‘Federico II’ Napoli Italy
| | - Alessandro Emendato
- Department of Chemical Sciences University of Naples ‘Federico II’ Napoli Italy
| | - Diletta Ami
- Department of Biotechnology and Biosciences University of Milano‐Bicocca Italy
| | - Douglas V. Laurents
- Institute of Physical Chemistry ‘Rocasolano’ Consejo Superior de Investigaciones Científicas Madrid Spain
| | - Antonino Natalello
- Department of Biotechnology and Biosciences University of Milano‐Bicocca Italy
| | - Roberta Spadaccini
- Department of Science and Technology Università degli Studi del Sannio Benevento Italy
| | - Delia Picone
- Department of Chemical Sciences University of Naples ‘Federico II’ Napoli Italy
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15
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Affiliation(s)
- Balaka Mondal
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru, Karnataka India, 560012
| | - Govardhan Reddy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru, Karnataka India, 560012
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16
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Abstract
Protein aggregation appears to originate from partially unfolded conformations that are sampled through stochastic fluctuations of the native protein. It has been a challenge to characterize these fluctuations, under native like conditions. Here, the conformational dynamics of the full-length (23-231) mouse prion protein were studied under native conditions, using photoinduced electron transfer coupled to fluorescence correlation spectroscopy (PET-FCS). The slowest fluctuations could be associated with the folding of the unfolded state to an intermediate state, by the use of microsecond mixing experiments. The two faster fluctuations observed by PET-FCS, could be attributed to fluctuations within the native state ensemble. The addition of salt, which is known to initiate the aggregation of the protein, resulted in an enhancement in the time scale of fluctuations in the core of the protein. The results indicate the importance of native state dynamics in initiating the aggregation of proteins.
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Affiliation(s)
- Rama Reddy Goluguri
- National Centre for Biological SciencesTata Institute of Fundamental ResearchBengaluruIndia
| | - Sreemantee Sen
- National Centre for Biological SciencesTata Institute of Fundamental ResearchBengaluruIndia
| | - Jayant Udgaonkar
- National Centre for Biological SciencesTata Institute of Fundamental ResearchBengaluruIndia
- Indian Institute of Science Education and ResearchPuneIndia
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17
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Moulick R, Goluguri RR, Udgaonkar JB. Ruggedness in the Free Energy Landscape Dictates Misfolding of the Prion Protein. J Mol Biol 2019; 431:807-824. [DOI: 10.1016/j.jmb.2018.12.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 11/15/2018] [Accepted: 12/16/2018] [Indexed: 12/12/2022]
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18
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Patel JR, Xu Y, Capitini C, Chiti F, De Simone A. Backbone NMR assignments of HypF-N under conditions generating toxic and non-toxic oligomers. Biomol NMR Assign 2018; 12:273-277. [PMID: 29786756 PMCID: PMC6132818 DOI: 10.1007/s12104-018-9822-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 04/24/2018] [Indexed: 06/08/2023]
Abstract
The HypF protein is involved in the maturation and regulation of hydrogenases. The N-terminal domain of HypF (HypF-N) has served as a key model system to study the pathways of protein amyloid formation and the nature of the toxicity of pre-fibrilar protein oligomers. This domain can aggregate into two forms of oligomers having significantly different toxic effects when added to neuronal cultures. Here, NMR assignments of HypF-N backbone resonances are presented in its native state and under the conditions favouring the formation of toxic and non-toxic oligomers. The analyses of chemical shifts provide insights into the protein conformational state and the possible pathways leading to the formation of different types of oligomers.
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Affiliation(s)
- Jayneil R Patel
- Department of Life Sciences, Imperial College London, South Kensington, London, SW72AZ, UK
| | - Yingqi Xu
- Department of Life Sciences, Imperial College London, South Kensington, London, SW72AZ, UK
| | - Claudia Capitini
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, 50134, Firenze, Italy
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, Viale Morgagni 50, 50134, Firenze, Italy
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, South Kensington, London, SW72AZ, UK.
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19
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Koçillari L, Fariselli P, Trovato A, Seno F, Maritan A. Signature of Pareto optimization in the Escherichia coli proteome. Sci Rep 2018; 8:9141. [PMID: 29904084 PMCID: PMC6002381 DOI: 10.1038/s41598-018-27287-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 05/15/2018] [Indexed: 01/20/2023] Open
Abstract
Proteins have coevolved with cellular environments to improve or preserve their functions, maintaining at the same time the degree of hydrophobicity necessary to fold correctly and enough solubility to perform their biological roles. Here, we study the Escherichia coli proteome using a Pareto front analysis in the solubility-hydrophobicity space. The results indicate the existence of a Pareto optimal front, a triangle whose vertices correspond to archetypal proteins specialized in distinct tasks, such as regulatory processes, membrane transport, outer-membrane pore formation, catalysis, and binding. The vertices are further enriched with proteins that occupy different subcellular compartments, namely, cytoplasmic, inner membrane, outer membrane, and outer membrane bounded periplasmic space. The combination of various enriching features offers an interpretation of how bacteria use the physico-chemical properties of proteins, both to drive them into their final destination in the cell and to have their tasks accomplished.
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Affiliation(s)
- Loren Koçillari
- INFN and Dipartimento di Fisica e Astronomia 'G. Galilei', Università di Padova, Via Marzolo 8, Padova, 35131, IT, Italy
| | - Piero Fariselli
- Dipartimento di Biomedicina Comparata e Alimentazione, Università di Padova, Viale dell' Università 16, Legnaro, 35020, IT, Italy
| | - Antonio Trovato
- INFN and Dipartimento di Fisica e Astronomia 'G. Galilei', Università di Padova, Via Marzolo 8, Padova, 35131, IT, Italy
| | - Flavio Seno
- INFN and Dipartimento di Fisica e Astronomia 'G. Galilei', Università di Padova, Via Marzolo 8, Padova, 35131, IT, Italy
| | - Amos Maritan
- INFN and Dipartimento di Fisica e Astronomia 'G. Galilei', Università di Padova, Via Marzolo 8, Padova, 35131, IT, Italy.
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20
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Kunz P, Zinner K, Mücke N, Bartoschik T, Muyldermans S, Hoheisel JD. The structural basis of nanobody unfolding reversibility and thermoresistance. Sci Rep 2018; 8:7934. [PMID: 29784954 DOI: 10.1038/s41598-018-26338-z] [Citation(s) in RCA: 91] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 05/10/2018] [Indexed: 12/17/2022] Open
Abstract
Nanobodies represent the variable binding domain of camelid heavy-chain antibodies and are employed in a rapidly growing range of applications in biotechnology and biomedicine. Their success is based on unique properties including their reported ability to reversibly refold after heat-induced denaturation. This view, however, is contrasted by studies which involve irreversibly aggregating nanobodies, asking for a quantitative analysis that clearly defines nanobody thermoresistance and reveals the determinants of unfolding reversibility and aggregation propensity. By characterizing nearly 70 nanobodies, we show that irreversible aggregation does occur upon heat denaturation for the large majority of binders, potentially affecting application-relevant parameters like stability and immunogenicity. However, by deriving aggregation propensities from apparent melting temperatures, we show that an optional disulfide bond suppresses nanobody aggregation. This effect is further enhanced by increasing the length of a complementarity determining loop which, although expected to destabilize, contributes to nanobody stability. The effect of such variations depends on environmental conditions, however. Nanobodies with two disulfide bonds, for example, are prone to lose their functionality in the cytosol. Our study suggests strategies to engineer nanobodies that exhibit optimal performance parameters and gives insights into general mechanisms which evolved to prevent protein aggregation.
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21
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Fusco G, Sanz-Hernandez M, Ruggeri FS, Vendruscolo M, Dobson CM, De Simone A. Molecular determinants of the interaction of EGCG with ordered and disordered proteins. Biopolymers 2018; 109:e23117. [DOI: 10.1002/bip.23117] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 03/07/2018] [Accepted: 03/07/2018] [Indexed: 12/31/2022]
Affiliation(s)
- Giuliana Fusco
- Department of Life Sciences; Imperial College London; London SW7 2AZ United Kingdom
- Centre for Misfolding Diseases, Department of Chemistry; University of Cambridge; Cambridge CB2 1EW United Kingdom
| | | | - Francesco S. Ruggeri
- Centre for Misfolding Diseases, Department of Chemistry; University of Cambridge; Cambridge CB2 1EW United Kingdom
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Department of Chemistry; University of Cambridge; Cambridge CB2 1EW United Kingdom
| | - Christopher M. Dobson
- Centre for Misfolding Diseases, Department of Chemistry; University of Cambridge; Cambridge CB2 1EW United Kingdom
| | - Alfonso De Simone
- Department of Life Sciences; Imperial College London; London SW7 2AZ United Kingdom
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22
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Oberti L, Rognoni P, Barbiroli A, Lavatelli F, Russo R, Maritan M, Palladini G, Bolognesi M, Merlini G, Ricagno S. Concurrent structural and biophysical traits link with immunoglobulin light chains amyloid propensity. Sci Rep 2017; 7:16809. [PMID: 29196671 DOI: 10.1038/s41598-017-16953-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/10/2017] [Indexed: 01/08/2023] Open
Abstract
Light chain amyloidosis (AL), the most common systemic amyloidosis, is caused by the overproduction and the aggregation of monoclonal immunoglobulin light chains (LC) in target organs. Due to genetic rearrangement and somatic hypermutation, virtually, each AL patient presents a different amyloidogenic LC. Because of such complexity, the fine molecular determinants of LC aggregation propensity and proteotoxicity are, to date, unclear; significantly, their decoding requires investigating large sets of cases. Aiming to achieve generalizable observations, we systematically characterised a pool of thirteen sequence-diverse full length LCs. Eight amyloidogenic LCs were selected as responsible for severe cardiac symptoms in patients; five non-amyloidogenic LCs were isolated from patients affected by multiple myeloma. Our comprehensive approach (consisting of spectroscopic techniques, limited proteolysis, and X-ray crystallography) shows that low fold stability and high protein dynamics correlate with amyloidogenic LCs, while hydrophobicity, structural rearrangements and nature of the LC dimeric association interface (as observed in seven crystal structures here presented) do not appear to play a significant role in defining amyloid propensity. Based on the structural and biophysical data, our results highlight shared properties driving LC amyloid propensity, and these data will be instrumental for the design of synthetic inhibitors of LC aggregation.
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23
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Abstract
Protein sequences are evolved to encode generally one folded structure, out of a nearly infinite array of possible folds. Underlying this code is a funneled free energy landscape that guides folding to the native conformation. Protein misfolding and aggregation are also a manifestation of free-energy landscapes. The detailed mechanisms of these processes are poorly understood, but often involve rare, transient species and a variety of different pathways. The inherent complexity of misfolding has hampered efforts to measure aggregation pathways and the underlying energy landscape, especially using traditional methods where ensemble averaging obscures important rare and transient events. We recently studied the misfolding and aggregation of prion protein by examining 2 monomers tethered in close proximity as a dimer, showing how the steps leading to the formation of a stable aggregated state can be resolved in the single-molecule limit and the underlying energy landscape thereby reconstructed. This approach allows a more quantitative comparison of native folding versus misfolding, including fundamental differences in the dynamics for misfolding. By identifying key steps and interactions leading to misfolding, it should help to identify potential drug targets. Here we describe the importance of characterizing free-energy landscapes for aggregation and the challenges involved in doing so, and we discuss how single-molecule studies can help test proposed structural models for PrP aggregates.
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Affiliation(s)
- Derek R Dee
- a Department of Physics , University of Alberta , Edmonton , AB , Canada
| | - Michael T Woodside
- a Department of Physics , University of Alberta , Edmonton , AB , Canada;,b National Institute for Nanotechnology, National Research Council , Edmonton , AB , Canada
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24
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Elia F, Cantini F, Chiti F, Dobson CM, Bemporad F. Direct Conversion of an Enzyme from Native-like to Amyloid-like Aggregates within Inclusion Bodies. Biophys J 2017; 112:2540-2551. [PMID: 28636911 PMCID: PMC5479110 DOI: 10.1016/j.bpj.2017.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 05/02/2017] [Accepted: 05/08/2017] [Indexed: 01/29/2023] Open
Abstract
The acylphosphatase from Sulfolobus solfataricus (Sso AcP) is a globular protein able to aggregate in vitro from a native-like conformational ensemble without the need for a transition across the major unfolding energy barrier. This process leads to the formation of assemblies in which the protein retains its native-like structure, which subsequently convert into amyloid-like aggregates. Here, we investigate the mechanism by which Sso AcP aggregates in vivo to form bacterial inclusion bodies after expression in E. coli. Shortly after the initiation of expression, Sso AcP is incorporated into inclusion bodies as a native-like protein, still exhibiting small but significant enzymatic activity. Additional experiments revealed that this overall process of aggregation is enhanced by the presence of the unfolded N-terminal region of the sequence and by destabilization of the globular segment of the protein. At later times, the Sso AcP molecules in the inclusion bodies lose their native-like properties and convert into β-sheet-rich amyloid-like structures, as indicated by their ability to bind thioflavin T and Congo red. These results show that the aggregation behavior of this protein is similar in vivo to that observed in vitro, and that, at least for a predominant part of the protein population, the transition from a native to an amyloid-like structure occurs within the aggregate state.
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Affiliation(s)
- Francesco Elia
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Firenze, Italy
| | - Francesca Cantini
- Centro Risonanze Magnetiche (CERM) and Department of Chemistry, University of Florence, Sesto Fiorentino, Italy
| | - Fabrizio Chiti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Firenze, Italy
| | | | - Francesco Bemporad
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio," University of Florence, Firenze, Italy.
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25
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Abstract
Szent-Győrgi called water the "matrix of life" and claimed that there was no life without it. This statement is true, as far as we know, on our planet, but it is not clear whether it must hold throughout the cosmos. To evaluate that question requires a close consideration of the many varied and subtle roles that water plays in living cells-a consideration that must be free of both an assumed essentialism that gives water an almost mystical life-giving agency and a traditional tendency to see it as a merely passive solvent. Water is a participant in the "life of the cell," and here I describe some of the features of that active agency. Water's value for molecular biology comes from both the structural and dynamic characteristics of its status as a complex, structured liquid as well as its nature as a polar, protic, and amphoteric reagent. Any discussion of water as life's matrix must, however, begin with an acknowledgment that our understanding of it as both a liquid and a solvent is still incomplete.
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26
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Moulick R, Udgaonkar JB. Identification and Structural Characterization of the Precursor Conformation of the Prion Protein which Directly Initiates Misfolding and Oligomerization. J Mol Biol 2017; 429:886-899. [DOI: 10.1016/j.jmb.2017.01.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 01/19/2017] [Accepted: 01/19/2017] [Indexed: 12/11/2022]
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27
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Abstract
DNA intercalators modulate amyloid assembly of proteins through specific hetero-aromatic interactions diverting them to form amorphous aggregates.
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Affiliation(s)
- Jasdeep Singh
- Kusuma School of Biological Sciences
- Indian Institute of Technology Delhi
- New Delhi
- India
| | - Ankit Srivastava
- Kusuma School of Biological Sciences
- Indian Institute of Technology Delhi
- New Delhi
- India
| | - Pankaj Sharma
- Kusuma School of Biological Sciences
- Indian Institute of Technology Delhi
- New Delhi
- India
| | - Prashant Pradhan
- Kusuma School of Biological Sciences
- Indian Institute of Technology Delhi
- New Delhi
- India
| | - Bishwajit Kundu
- Kusuma School of Biological Sciences
- Indian Institute of Technology Delhi
- New Delhi
- India
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28
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Bemporad F, Ramazzotti M. From the Evolution of Protein Sequences Able to Resist Self-Assembly to the Prediction of Aggregation Propensity. Int Rev Cell Mol Biol 2016; 329:1-47. [PMID: 28109326 DOI: 10.1016/bs.ircmb.2016.08.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Folding of polypeptide chains into biologically active entities is an astonishingly complex process, determined by the nature and the sequence of residues emerging from ribosomes. While it has been long believed that evolution has pressed genomes so that specific sequences could adopt unique, functional three-dimensional folds, it is now clear that complex protein machineries act as quality control system and supervise folding. Notwithstanding that, events such as erroneous folding, partial folding, or misfolding are frequent during the life of a cell or a whole organism, and they can escape controls. One of the possible outcomes of this misbehavior is cross-β aggregation, a super secondary structure which represents the hallmark of self-assembled, well organized, and extremely ordered structures termed amyloid fibrils. What if evolution would have not taken into account such possibilities? Twenty years of research point toward the idea that, in fact, evolution has constantly supervised the risk of errors and minimized their impact. In this review we tried to survey the major findings in the amyloid field, trying to describe what the real pitfalls of protein folding are-from an evolutionary perspective-and how sequence and structural features have evolved to balance the need for perfect, dynamic, functionally efficient structures, and the detrimental effects implicit in the dangerous process of folding. We will discuss how the knowledge obtained from these studies has been employed to produce computational methods able to assess, predict, and discriminate the aggregation properties of protein sequences.
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Affiliation(s)
- F Bemporad
- Università degli Studi di Firenze, Firenze, Italy.
| | - M Ramazzotti
- Università degli Studi di Firenze, Firenze, Italy.
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29
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Li W, Prabakaran P, Chen W, Zhu Z, Feng Y, Dimitrov DS. Antibody Aggregation: Insights from Sequence and Structure. Antibodies (Basel) 2016; 5:antib5030019. [PMID: 31558000 PMCID: PMC6698864 DOI: 10.3390/antib5030019] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Revised: 08/03/2016] [Accepted: 08/04/2016] [Indexed: 12/12/2022] Open
Abstract
Monoclonal antibodies (mAbs) are the fastest-growing biological therapeutics with important applications ranging from cancers, autoimmunity diseases and metabolic disorders to emerging infectious diseases. Aggregation of mAbs continues to be a major problem in their developability. Antibody aggregation could be triggered by partial unfolding of its domains, leading to monomer-monomer association followed by nucleation and growth. Although the aggregation propensities of antibodies and antibody-based proteins can be affected by the external experimental conditions, they are strongly dependent on the intrinsic antibody properties as determined by their sequences and structures. In this review, we describe how the unfolding and aggregation susceptibilities of IgG could be related to their cognate sequences and structures. The impact of antibody domain structures on thermostability and aggregation propensities, and effective strategies to reduce aggregation are discussed. Finally, the aggregation of antibody-drug conjugates (ADCs) as related to their sequence/structure, linker payload, conjugation chemistry and drug-antibody ratio (DAR) is reviewed.
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Affiliation(s)
- Wei Li
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA.
| | | | - Weizao Chen
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA.
| | - Zhongyu Zhu
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA.
| | - Yang Feng
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA.
| | - Dimiter S Dimitrov
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA.
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30
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Camilloni C, Sala BM, Sormanni P, Porcari R, Corazza A, De Rosa M, Zanini S, Barbiroli A, Esposito G, Bolognesi M, Bellotti V, Vendruscolo M, Ricagno S. Rational design of mutations that change the aggregation rate of a protein while maintaining its native structure and stability. Sci Rep 2016; 6:25559. [PMID: 27150430 PMCID: PMC4858664 DOI: 10.1038/srep25559] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 04/20/2016] [Indexed: 01/27/2023] Open
Abstract
A wide range of human diseases is associated with mutations that, destabilizing proteins native state, promote their aggregation. However, the mechanisms leading from folded to aggregated states are still incompletely understood. To investigate these mechanisms, we used a combination of NMR spectroscopy and molecular dynamics simulations to compare the native state dynamics of Beta-2 microglobulin (β2m), whose aggregation is associated with dialysis-related amyloidosis, and its aggregation-resistant mutant W60G. Our results indicate that W60G low aggregation propensity can be explained, beyond its higher stability, by an increased average protection of the aggregation-prone residues at its surface. To validate these findings, we designed β2m variants that alter the aggregation-prone exposed surface of wild-type and W60G β2m modifying their aggregation propensity. These results allowed us to pinpoint the role of dynamics in β2m aggregation and to provide a new strategy to tune protein aggregation by modulating the exposure of aggregation-prone residues.
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Affiliation(s)
- Carlo Camilloni
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK.,Department of Chemistry and Institute for Advanced Study, Technische Universität München, Lichtenbergstraße 4, D-85748 Garching, Germany
| | - Benedetta Maria Sala
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133 Milano, Italy
| | - Pietro Sormanni
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Riccardo Porcari
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, University College London, London NW3 2PF, UK
| | - Alessandra Corazza
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, 33100 Udine, Italy
| | - Matteo De Rosa
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133 Milano, Italy
| | - Stefano Zanini
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, 33100 Udine, Italy
| | - Alberto Barbiroli
- Dipartimento di Scienze per gli Alimenti, la Nutrizione e l'Ambiente, Università degli Studi di Milano, 20133 Milano, Italy
| | - Gennaro Esposito
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, 33100 Udine, Italy.,Science and Math Division, New York University Abu Dhabi, Saadiyat Island, Abu Dhabi, UAE
| | - Martino Bolognesi
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133 Milano, Italy.,CIMAINA and CNR Istituto di Biofisica, c/o Dipartimento di Bioscienze, Università degli Studi di Milano, 20133 Milano, Italy
| | - Vittorio Bellotti
- Wolfson Drug Discovery Unit, Centre for Amyloidosis and Acute Phase Proteins, University College London, London NW3 2PF, UK
| | | | - Stefano Ricagno
- Dipartimento di Bioscienze, Università degli Studi di Milano, 20133 Milano, Italy
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31
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Sanz-Hernández M, Vostrikov VV, Veglia G, De Simone A. Accurate Determination of Conformational Transitions in Oligomeric Membrane Proteins. Sci Rep 2016; 6:23063. [PMID: 26975211 DOI: 10.1038/srep23063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/25/2016] [Indexed: 12/27/2022] Open
Abstract
The structural dynamics governing collective motions in oligomeric membrane proteins play key roles in vital biomolecular processes at cellular membranes. In this study, we present a structural refinement approach that combines solid-state NMR experiments and molecular simulations to accurately describe concerted conformational transitions identifying the overall structural, dynamical, and topological states of oligomeric membrane proteins. The accuracy of the structural ensembles generated with this method is shown to reach the statistical error limit, and is further demonstrated by correctly reproducing orthogonal NMR data. We demonstrate the accuracy of this approach by characterising the pentameric state of phospholamban, a key player in the regulation of calcium uptake in the sarcoplasmic reticulum, and by probing its dynamical activation upon phosphorylation. Our results underline the importance of using an ensemble approach to characterise the conformational transitions that are often responsible for the biological function of oligomeric membrane protein states.
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32
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Affiliation(s)
- Conan K. Wang
- Institute
for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Joakim E. Swedberg
- Institute
for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Susan E. Northfield
- Institute
for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David J. Craik
- Institute
for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
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33
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Granata D, Baftizadeh F, Habchi J, Galvagnion C, De Simone A, Camilloni C, Laio A, Vendruscolo M. The inverted free energy landscape of an intrinsically disordered peptide by simulations and experiments. Sci Rep 2015; 5:15449. [PMID: 26498066 DOI: 10.1038/srep15449] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 06/22/2015] [Indexed: 11/24/2022] Open
Abstract
The free energy landscape theory has been very successful in rationalizing the folding behaviour of globular proteins, as this representation provides intuitive information on the number of states involved in the folding process, their populations and pathways of interconversion. We extend here this formalism to the case of the Aβ40 peptide, a 40-residue intrinsically disordered protein fragment associated with Alzheimer’s disease. By using an advanced sampling technique that enables free energy calculations to reach convergence also in the case of highly disordered states of proteins, we provide a precise structural characterization of the free energy landscape of this peptide. We find that such landscape has inverted features with respect to those typical of folded proteins. While the global free energy minimum consists of highly disordered structures, higher free energy regions correspond to a large variety of transiently structured conformations with secondary structure elements arranged in several different manners, and are not separated from each other by sizeable free energy barriers. From this peculiar structure of the free energy landscape we predict that this peptide should become more structured and not only more compact, with increasing temperatures, and we show that this is the case through a series of biophysical measurements.
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34
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Zambrano R, Jamroz M, Szczasiuk A, Pujols J, Kmiecik S, Ventura S. AGGRESCAN3D (A3D): server for prediction of aggregation properties of protein structures. Nucleic Acids Res 2015; 43:W306-13. [PMID: 25883144 PMCID: PMC4489226 DOI: 10.1093/nar/gkv359] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 04/07/2015] [Indexed: 11/14/2022] Open
Abstract
Protein aggregation underlies an increasing number of disorders and constitutes a major bottleneck in the development of therapeutic proteins. Our present understanding on the molecular determinants of protein aggregation has crystalized in a series of predictive algorithms to identify aggregation-prone sites. A majority of these methods rely only on sequence. Therefore, they find difficulties to predict the aggregation properties of folded globular proteins, where aggregation-prone sites are often not contiguous in sequence or buried inside the native structure. The AGGRESCAN3D (A3D) server overcomes these limitations by taking into account the protein structure and the experimental aggregation propensity scale from the well-established AGGRESCAN method. Using the A3D server, the identified aggregation-prone residues can be virtually mutated to design variants with increased solubility, or to test the impact of pathogenic mutations. Additionally, A3D server enables to take into account the dynamic fluctuations of protein structure in solution, which may influence aggregation propensity. This is possible in A3D Dynamic Mode that exploits the CABS-flex approach for the fast simulations of flexibility of globular proteins. The A3D server can be accessed at http://biocomp.chem.uw.edu.pl/A3D/.
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Affiliation(s)
- Rafael Zambrano
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain
| | - Michal Jamroz
- University of Warsaw, Faculty of Chemistry, Pasteura 1, Warsaw, Poland
| | - Agata Szczasiuk
- University of Warsaw, Faculty of Chemistry, Pasteura 1, Warsaw, Poland
| | - Jordi Pujols
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain
| | - Sebastian Kmiecik
- University of Warsaw, Faculty of Chemistry, Pasteura 1, Warsaw, Poland
| | - Salvador Ventura
- Institut de Biotecnologia i Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain
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Di Silvio E, Toto A, Bonetti D, Morrone A, Gianni S. Understanding the effect of alternative splicing in the folding and function of the second PDZ from protein tyrosine phosphatase-BL. Sci Rep 2015; 5:9299. [PMID: 25788329 PMCID: PMC4365404 DOI: 10.1038/srep09299] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 02/26/2015] [Indexed: 11/10/2022] Open
Abstract
PDZ domains are the most prominent biological structural domains involved in protein-protein interactions in the human cell. The second PDZ domain of the protein tyrosine phosphatase BL (PDZ2) interacts and binds the C-termini of the tumour suppressor protein APC and of the LIM domain-containing protein RIL. One isoform of PDZ2 (PDZ2as) involves an alternative spliced form that exhibits an insertion of 5 residues in a loop. PDZ2as abrogates binding to its partners, even if the insertion is directly located in its binding pocket. Here, we investigate the folding and function of PDZ2as, in comparison to the previously characterized PDZ2 domain. Data reveal that, whilst the thermodynamic stability of PDZ2as appears as nearly identical to that of PDZ2, the insertion of 5 amino acids induces formation of some weak transient non-native interactions in the folding transition state, as mirrored by a concomitant increase of both the folding and unfolding rate constants. From a functional perspective, we show that the decrease in affinity is caused by a pronounced decrease of the association rate constants (by nearly ten fold), with no effect on the microscopic dissociation rate constants. The results are briefly discussed in the context of previous work on PDZ domains.
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Affiliation(s)
- Eva Di Silvio
- Istituto Pasteur - Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Angelo Toto
- Istituto Pasteur - Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Daniela Bonetti
- Istituto Pasteur - Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Angela Morrone
- Istituto Pasteur - Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy
| | - Stefano Gianni
- 1] Istituto Pasteur - Fondazione Cenci Bolognetti and Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Scienze Biochimiche "A. Rossi Fanelli", Sapienza Università di Roma, P.le A. Moro 5, 00185, Rome, Italy [2] Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom
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De Simone A, Mote KR, Veglia G. Structural dynamics and conformational equilibria of SERCA regulatory proteins in membranes by solid-state NMR restrained simulations. Biophys J 2015; 106:2566-76. [PMID: 24940774 DOI: 10.1016/j.bpj.2014.03.026] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 03/14/2014] [Accepted: 03/19/2014] [Indexed: 01/08/2023] Open
Abstract
Solid-state NMR spectroscopy is emerging as a powerful approach to determine structure, topology, and conformational dynamics of membrane proteins at the atomic level. Conformational dynamics are often inferred and quantified from the motional averaging of the NMR parameters. However, the nature of these motions is difficult to envision based only on spectroscopic data. Here, we utilized restrained molecular dynamics simulations to probe the structural dynamics, topology and conformational transitions of regulatory membrane proteins of the calcium ATPase SERCA, namely sarcolipin and phospholamban, in explicit lipid bilayers. Specifically, we employed oriented solid-state NMR data, such as dipolar couplings and chemical shift anisotropy measured in lipid bicelles, to refine the conformational ensemble of these proteins in lipid membranes. The samplings accurately reproduced the orientations of transmembrane helices and showed a significant degree of convergence with all of the NMR parameters. Unlike the unrestrained simulations, the resulting sarcolipin structures are in agreement with distances and angles for hydrogen bonds in ideal helices. In the case of phospholamban, the restrained ensemble sampled the conformational interconversion between T (helical) and R (unfolded) states for the cytoplasmic region that could not be observed using standard structural refinements with the same experimental data set. This study underscores the importance of implementing NMR data in molecular dynamics protocols to better describe the conformational landscapes of membrane proteins embedded in realistic lipid membranes.
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Affiliation(s)
- Alfonso De Simone
- Department of Life Sciences, Imperial College London, London, United Kingdom.
| | - Kaustubh R Mote
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota
| | - Gianluigi Veglia
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota; Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, Minneapolis, Minnesota.
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Krieger JM, Fusco G, Lewitzky M, Simister PC, Marchant J, Camilloni C, Feller SM, De Simone A. Conformational recognition of an intrinsically disordered protein. Biophys J 2014; 106:1771-9. [PMID: 24739176 DOI: 10.1016/j.bpj.2014.03.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Revised: 03/02/2014] [Accepted: 03/06/2014] [Indexed: 10/25/2022] Open
Abstract
There is a growing interest in understanding the properties of intrinsically disordered proteins (IDPs); however, the characterization of these states remains an open challenge. IDPs appear to have functional roles that diverge from those of folded proteins and revolve around their ability to act as hubs for protein-protein interactions. To gain a better understanding of the modes of binding of IDPs, we combined statistical mechanics, calorimetry, and NMR spectroscopy to investigate the recognition and binding of a fragment from the disordered protein Gab2 by the growth factor receptor-bound protein 2 (Grb2), a key interaction for normal cell signaling and cancer development. Structural ensemble refinement by NMR chemical shifts, thermodynamics measurements, and analysis of point mutations indicated that the population of preexisting bound conformations in the free-state ensemble of Gab2 is an essential determinant for recognition and binding by Grb2. A key role was found for transient polyproline II (PPII) structures and extended conformations. Our findings are likely to have very general implications for the biological behavior of IDPs in light of the evidence that a large fraction of these proteins possess a specific propensity to form PPII and to adopt conformations that are more extended than the typical random-coil states.
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Affiliation(s)
- James M Krieger
- Department of Life Sciences, Imperial College London, London, UK
| | - Giuliana Fusco
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Marc Lewitzky
- Department of Oncology, University of Oxford, Oxford, UK; Institute of Molecular Medicine, Martin Luther University Halle-Wittenberg, Halle, Germany
| | | | - Jan Marchant
- Department of Life Sciences, Imperial College London, London, UK
| | - Carlo Camilloni
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Stephan M Feller
- Department of Oncology, University of Oxford, Oxford, UK; Institute of Molecular Medicine, Martin Luther University Halle-Wittenberg, Halle, Germany
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Moulick R, Udgaonkar JB. Thermodynamic characterization of the unfolding of the prion protein. Biophys J 2014; 106:410-20. [PMID: 24461016 DOI: 10.1016/j.bpj.2013.11.4491] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 11/15/2013] [Accepted: 11/27/2013] [Indexed: 12/16/2022] Open
Abstract
The prion protein appears to be unusually susceptible to conformational change, and unlike nearly all other proteins, it can easily be made to convert to alternative misfolded conformations. To understand the basis of this structural plasticity, a detailed thermodynamic characterization of two variants of the mouse prion protein (moPrP), the full-length moPrP (23-231) and the structured C-terminal domain, moPrP (121-231), has been carried out. All thermodynamic parameters governing unfolding, including the changes in enthalpy, entropy, free energy, and heat capacity, were found to be identical for the two protein variants. The N-terminal domain remains unstructured and does not interact with the C-terminal domain in the full-length protein at pH 4. Moreover, the enthalpy and entropy of unfolding of moPrP (121-231) are similar in magnitude to values reported for other proteins of similar size. However, the protein has an unusually high native-state heat capacity, and consequently, the change in heat capacity upon unfolding is much lower than that expected for a protein of similar size. It appears, therefore, that the native state of the prion protein undergoes substantial fluctuations in enthalpy and hence, in structure.
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Affiliation(s)
- Roumita Moulick
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
| | - Jayant B Udgaonkar
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India.
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Iannuzzi C, Irace G, Sirangelo I. Differential effects of glycation on protein aggregation and amyloid formation. Front Mol Biosci 2014; 1:9. [PMID: 25988150 PMCID: PMC4428487 DOI: 10.3389/fmolb.2014.00009] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 08/08/2014] [Indexed: 12/28/2022] Open
Abstract
Amyloids are a class of insoluble proteinaceous substances generally composed of linear un-branched fibrils that are formed from misfolded proteins. Conformational diseases such as Alzheimer's disease, transmissible spongiform encephalopathies, and familial amyloidosis are associated with the presence of amyloid aggregates in the affected tissues. The majority of the cases are sporadic, suggesting that several factors must contribute to the onset and progression of these disorders. Among them, in the past 10 years, non-enzymatic glycation of proteins has been reported to stimulate protein aggregation and amyloid deposition. In this review, we analyze the most recent advances in this field suggesting that the effects induced by glycation may not be generalized as strongly depending on the protein structure. Indeed, being a post-translational modification, glycation could differentially affects the aggregation process in promoting, accelerating and/or stabilizing on-pathway and off-pathway species.
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Affiliation(s)
- Clara Iannuzzi
- Department of Biochemistry, Biophysics and General Pathology, Seconda Università degli Studi di Napoli Naples, Italy
| | - Gaetano Irace
- Department of Biochemistry, Biophysics and General Pathology, Seconda Università degli Studi di Napoli Naples, Italy
| | - Ivana Sirangelo
- Department of Biochemistry, Biophysics and General Pathology, Seconda Università degli Studi di Napoli Naples, Italy
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de Rosa M, Bemporad F, Pellegrino S, Chiti F, Bolognesi M, Ricagno S. Edge strand engineering prevents native-like aggregation in Sulfolobus solfataricus acylphosphatase. FEBS J 2014; 281:4072-84. [PMID: 24893801 DOI: 10.1111/febs.12861] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Revised: 05/19/2014] [Accepted: 05/23/2014] [Indexed: 01/09/2023]
Abstract
β-proteins are constantly threatened by the risk of aggregation because β-sheets are inherently structured for edge-to-edge interactions. To avoid native-like aggregation, evolution has resulted in a set of strategies that prevent intermolecular β-interactions. Acylphosphatase from Sulfolobus solfataricus (Sso AcP) represents a suitable model for the study of such a process. Under conditions promoting aggregation, Sso AcP acquires a native-like conformational state whereby an unstructured N-terminal segment interacts with the edge β-strand B4 of an adjacent Sso AcP molecule. Because B4 is poorly protected against aggregation, this interaction triggers the aggregation cascade without the need for unfolding. Recently, three single Sso AcP mutants (V84D, Y86E and V84P) were designed to engineer additional protection against aggregation in B4 and were observed to successfully impair native-like aggregation in all three variants at the expense of a lower stability. To understand the structural basis of the reduced aggregation propensity and lower stability, the crystal structures of the Sso AcP variants were determined in the present study. Structural analysis reveals that the V84D and Y86E mutations exert protection by the insertion of an edge negative charge. A conformationally less regular B4 underlies protection against aggregation in the V84P mutant. The thermodynamic basis of instability is discussed. Moreover, kinetic experiments indicate that aggregation of the three mutants is not native-like and is independent of the interaction between B4 and the unstructured N-terminal segment. The reported data rationalize previous evidence regarding Sso AcP native-like aggregation and provide a basis for the design of aggregation-free proteins. DATABASE The atomic coordinates and related experimental data for the Sso AcP mutants V84P, V84D, ΔN11 Y86E have been deposited in the Protein Data Bank under accession numbers 4OJ3, 4OJG and 4OJH, respectively. STRUCTURED DIGITAL ABSTRACT • Sso AcP and Sso AcP bind by fluorescence technology (View interaction).
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41
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Zhuravlev PI, Reddy G, Straub JE, Thirumalai D. Propensity to form amyloid fibrils is encoded as excitations in the free energy landscape of monomeric proteins. J Mol Biol 2014; 426:2653-66. [PMID: 24846645 PMCID: PMC4100209 DOI: 10.1016/j.jmb.2014.05.007] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 05/03/2014] [Accepted: 05/12/2014] [Indexed: 02/05/2023]
Abstract
Protein aggregation, linked to many of diseases, is initiated when monomers access rogue conformations that are poised to form amyloid fibrils. We show, using simulations of src SH3 domain, that mechanical force enhances the population of the aggregation-prone (N(⁎)) states, which are rarely populated under force free native conditions but are encoded in the spectrum of native fluctuations. The folding phase diagrams of SH3 as a function of denaturant concentration ([C]), mechanical force (f), and temperature exhibit an apparent two-state behavior, without revealing the presence of the elusive N(⁎) states. Interestingly, the phase boundaries separating the folded and unfolded states at all [C] and f fall on a master curve, which can be quantitatively described using an analogy to superconductors in a magnetic field. The free energy profiles as a function of the molecular extension (R), which are accessible in pulling experiments, (R), reveal the presence of a native-like N(⁎) with a disordered solvent-exposed amino-terminal β-strand. The structure of the N(⁎) state is identical with that found in Fyn SH3 by NMR dispersion experiments. We show that the timescale for fibril formation can be estimated from the population of the N(⁎) state, determined by the free energy gap separating the native structure and the N(⁎) state, a finding that can be used to assess fibril forming tendencies of proteins. The structures of the N(⁎) state are used to show that oligomer formation and likely route to fibrils occur by a domain-swap mechanism in SH3 domain.
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Affiliation(s)
- Pavel I Zhuravlev
- Biophysics Program, Institute for Physical Science and Technology, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Govardhan Reddy
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India
| | - John E Straub
- Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, MA 02215-2521, USA
| | - D Thirumalai
- Biophysics Program, Institute for Physical Science and Technology, Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.
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Balasco N, Esposito L, De Simone A, Vitagliano L. Role of loops connecting secondary structure elements in the stabilization of proteins isolated from thermophilic organisms. Protein Sci 2014; 22:1016-23. [PMID: 23661276 DOI: 10.1002/pro.2279] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 05/06/2013] [Accepted: 05/06/2013] [Indexed: 01/13/2023]
Abstract
It has been recently discovered that the connection of secondary structure elements (ββ-unit, βα- and αβ-units) in proteins follows quite stringent principles regarding the chirality and the orientation of the structural units (Koga et al., Nature 2012;491:222-227). By exploiting these rules, a number of protein scaffolds endowed with a remarkable thermal stability have been designed (Koga et al., Nature 2012;491:222-227). By using structural databases of proteins isolated from either mesophilic or thermophilic organisms, we here investigate the influence of supersecondary associations on the thermal stability of natural proteins. Our results suggest that β-hairpins of proteins from thermophilic organisms are very frequently characterized by shortenings of the loops. Interestingly, this shortening leads to states that display a very strong preference for the most common connectivity of the strands observed in native protein hairpins. The abundance of selective states in these proteins suggests that they may achieve a high stability by adopting a strategy aimed to reduce the possible conformations of the unfolded ensemble. In this scenario, our data indicate that the shortening is effective if it increases the adherence to these rules. We also show that this mechanism may operate in the stabilization of well-known protein folds (thioredoxin and RNase A). These findings suggest that future investigations aimed at defining mechanism of protein stabilization should also consider these effects.
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Affiliation(s)
- Nicole Balasco
- Institute of Biostructures and Bioimaging, C.N.R., Naples, I-80134, Italy
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Khoshtariya DE, Dolidze TD, Shushanyan M, van Eldik R. Long-range electron transfer with myoglobin immobilized at Au/mixed-SAM junctions: mechanistic impact of the strong protein confinement. J Phys Chem B 2014; 118:692-706. [PMID: 24369906 DOI: 10.1021/jp4101569] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Horse muscle myoglobin (Mb) was tightly immobilized at Au-deposited ~15-Å-thick mixed-type (1:1) alkanethiol SAMs, HS-(CH₂)₁₁-COOH/HS-(CH₂)₁₁-OH, and placed in contact with buffered H₂O or D₂O solutions. Fast-scan cyclic voltammetry (CV) and a Marcus-equation-based analysis were applied to determine unimolecular standard rate constants and reorganization free energies for electron transfer (ET), under variable-temperature (15-55 °C) and -pressure (0.01-150 MPa) conditions. The CV signal was surprisingly stable and reproducible even after multiple temperature and pressure cycles. The data analysis revealed the following values: standard rate constant, 33 s⁻¹ (25 °C, 0.01 MPa, H₂O); reorganization free energy, 0.5 ± 0.1 eV (throughout); activation enthalpy, 12 ± 3 kJ mol⁻¹; activation volume, -3.1 ± 0.2 cm³ mol⁻¹; and pH-dependent solvent kinetic isotope effect (k(H)⁰/k(D)⁰), 0.7-1.4. Furthermore, the values for the rate constant and reorganization free energy are very similar to those previously found for cytochrome c electrostatically immobilized at the monocomponent Au/HS-(CH₂)₁₁-COOH junction. In vivo, Mb apparently forms a natural electrostatic complex with cytochrome b₅ (cyt-b₅) through the "dynamic" (loose) docking pattern, allowing for a slow ET that is intrinsically coupled to the water's removal from the "defective" heme iron (altogether shaping the biological repair mechanism for Mb's "met" form). In contrary, our experiments rather mimic the case of a "simple" (tight) docking of the redesigned (mutant) Mb with cyt-b₅ (Nocek et al. J. Am. Chem. Soc. 2010, 132, 6165-6175). According to our analysis, in this configuration, Mb's distal pocket (linked to the "ligand channel") seems to be arrested within the restricted configuration, allowing the rate-determining reversible ET process to be coupled only to the inner-sphere reorganization (minimal elongation/shortening of an Fe-OH₂ bond) rather than the pronounced detachment (rebinding) of water and, hence, to be much faster.
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Affiliation(s)
- Dimitri E Khoshtariya
- Department of Chemistry and Pharmacy, University of Erlangen-Nürnberg , 91058 Erlangen, Germany
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Relini A, Marano N, Gliozzi A. Misfolding of amyloidogenic proteins and their interactions with membranes. Biomolecules 2013; 4:20-55. [PMID: 24970204 PMCID: PMC4030986 DOI: 10.3390/biom4010020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/13/2013] [Accepted: 12/17/2013] [Indexed: 01/07/2023] Open
Abstract
In this paper, we discuss amyloidogenic proteins, their misfolding, resulting structures, and interactions with membranes, which lead to membrane damage and subsequent cell death. Many of these proteins are implicated in serious illnesses such as Alzheimer’s disease and Parkinson’s disease. Misfolding of amyloidogenic proteins leads to the formation of polymorphic oligomers and fibrils. Oligomeric aggregates are widely thought to be the toxic species, however, fibrils also play a role in membrane damage. We focus on the structure of these aggregates and their interactions with model membranes. Study of interactions of amlyoidogenic proteins with model and natural membranes has shown the importance of the lipid bilayer in protein misfolding and aggregation and has led to the development of several models for membrane permeabilization by the resulting amyloid aggregates. We discuss several of these models: formation of structured pores by misfolded amyloidogenic proteins, extraction of lipids, interactions with receptors in biological membranes, and membrane destabilization by amyloid aggregates perhaps analogous to that caused by antimicrobial peptides.
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Affiliation(s)
- Annalisa Relini
- Department of Physics, University of Genoa, Genoa 16146, Italy.
| | - Nadia Marano
- Department of Physics, University of Genoa, Genoa 16146, Italy.
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Ferrolino MC, Zhuravleva A, Budyak IL, Krishnan B, Gierasch LM. Delicate balance between functionally required flexibility and aggregation risk in a β-rich protein. Biochemistry 2013; 52:8843-54. [PMID: 24236614 DOI: 10.1021/bi4013462] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Susceptibility to aggregation is general to proteins because of the potential for intermolecular interactions between hydrophobic stretches in their amino acid sequences. Protein aggregation has been implicated in several catastrophic diseases, yet we still lack in-depth understanding about how proteins are channeled to this state. Using a predominantly β-sheet protein whose folding has been explored in detail, cellular retinoic acid-binding protein 1 (CRABP1), as a model, we have tackled the challenge of understanding the links between a protein's natural tendency to fold, 'breathe', and function with its propensity to misfold and aggregate. We identified near-native dynamic species that lead to aggregation and found that inherent structural fluctuations in the native protein, resulting in opening of the ligand-entry portal, expose hydrophobic residues on the most vulnerable aggregation-prone sequences in CRABP1. CRABP1 and related intracellullar lipid-binding proteins have not been reported to aggregate inside cells, and we speculate that the cellular concentration of their open, aggregation-prone conformations is sufficient for ligand binding but below the critical concentration for aggregation. Our finding provides an example of how nature fine-tunes a delicate balance between protein function, conformational variability, and aggregation vulnerability and implies that with the evolutionary requirement for proteins to fold and function, aggregation becomes an unavoidable but controllable risk.
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Affiliation(s)
- Mylene C Ferrolino
- Department of Biochemistry and Molecular Biology, ‡Program in Molecular and Cellular Biology, and §Department of Chemistry, University of Massachusetts , Amherst, Massachusetts 01003, United States
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Mercadante D, Melton LD, Jameson GB, Williams MAK, De Simone A. Substrate dynamics in enzyme action: rotations of monosaccharide subunits in the binding groove are essential for pectin methylesterase processivity. Biophys J 2013; 104:1731-9. [PMID: 23601320 DOI: 10.1016/j.bpj.2013.02.049] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 02/13/2013] [Accepted: 02/25/2013] [Indexed: 01/31/2023] Open
Abstract
The dynamical behavior of biomacromolecules is a fundamental property regulating a large number of biological processes. Protein dynamics have been widely shown to play a role in enzyme catalysis; however, the interplay between substrate dynamics and enzymatic activity is less understood. We report insights into the role of dynamics of substrates in the enzymatic activity of PME from Erwinia chrysanthemi, a processive enzyme that catalyzes the hydrolysis of methylester groups from the galacturonic acid residues of homogalacturonan chains, the major component of pectin. Extensive molecular dynamics simulations of this PME in complex with decameric homogalacturonan chains possessing different degrees and patterns of methylesterification show how the carbohydrate substitution pattern governs the dynamics of the substrate in the enzyme's binding cleft, such that substrate dynamics represent a key prerequisite for the PME biological activity. The analyses reveal that correlated rotations around glycosidic bonds of monosaccharide subunits at and immediately adjacent to the active site are a necessary step to ensure substrate processing. Moreover, only substrates with the optimal methylesterification pattern attain the correct dynamical behavior to facilitate processive catalysis. This investigation is one of the few reported examples of a process where the dynamics of a substrate are vitally important.
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Ruggiero A, De Simone P, Smaldone G, Squeglia F, Berisio R. Bacterial cell division regulation by Ser/Thr kinases: a structural perspective. Curr Protein Pept Sci 2013; 13:756-66. [PMID: 23305362 PMCID: PMC3601408 DOI: 10.2174/138920312804871201] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/16/2012] [Accepted: 08/03/2012] [Indexed: 12/17/2022]
Abstract
Recent genetic, biochemical and structural studies have established that eukaryotic-like Ser/Thr protein-kinases are critical mediators of developmental changes and host pathogen interactions in bacteria. Although with lower abundance compared to their homologues from eukaryotes, Ser/Thr protein-kinases are widespread in gram-positive bacteria. These data underline a key role of reversible Ser/Thr phosphorylation in bacterial physiology and virulence. Numerous studies have revealed how phosphorylation/dephosphorylation of Ser/Thr protein-kinases governs cell division and cell wall biosynthesis and that Ser/Thr protein kinases are responsible for distinct phenotypes, dependent on different environmental signals. In this review we discuss the current understandings of Ser/Thr protein-kinases functional processes based on structural data.
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Affiliation(s)
- Alessia Ruggiero
- Institute of Biostructure and Bioimaging, CNR, Via Mezzocannone, 16. I-80134, Napoli, Italy.
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Cecchi C, Stefani M. The amyloid-cell membrane system. The interplay between the biophysical features of oligomers/fibrils and cell membrane defines amyloid toxicity. Biophys Chem 2013; 182:30-43. [PMID: 23820236 DOI: 10.1016/j.bpc.2013.06.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/03/2013] [Accepted: 06/03/2013] [Indexed: 12/14/2022]
Abstract
Amyloid cytotoxicity, structure and polymorphisms are themes of increasing importance. Present knowledge considers any peptide/protein able to undergo misfolding and aggregation generating intrinsically cytotoxic amyloids. It also describes growth and structure of amyloid fibrils and their possible disassembly, whereas reduced information is available on oligomer structure. Recent research has highlighted the importance of the environmental conditions as determinants of the amyloid polymorphisms and cytotoxicity. Another body of evidence describes chemical or biological surfaces as key sites of protein misfolding and aggregation or of interaction with amyloids and the resulting biochemical modifications inducing cell functional/viability impairment. In particular, the membrane lipid composition appears to modulate cell response to toxic amyloids, thus contributing to explain the variable vulnerability to the same amyloids of different cell types. Finally, a recent view describes amyloid toxicity as an emerging property dependent on a complex interplay between the biophysical features of early aggregates and the interacting cell membranes taken as a whole system.
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Affiliation(s)
- Cristina Cecchi
- Department of Biomedical Experimental and Clinical Sciences and Research Centre on the Molecular Basis of Neurodegeneration, University of Florence, Florence, Italy
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Wang X, Kumar S, Buck PM, Singh SK. Impact of deglycosylation and thermal stress on conformational stability of a full length murine igG2a monoclonal antibody: Observations from molecular dynamics simulations. Proteins 2012; 81:443-60. [DOI: 10.1002/prot.24202] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 10/02/2012] [Accepted: 10/04/2012] [Indexed: 12/13/2022]
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Krobath H, Estácio S, Faísca P, Shakhnovich E. Identification of a Conserved Aggregation-Prone Intermediate State in the Folding Pathways of Spc-SH3 Amyloidogenic Variants. J Mol Biol 2012; 422:705-722. [DOI: 10.1016/j.jmb.2012.06.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2012] [Revised: 06/11/2012] [Accepted: 06/11/2012] [Indexed: 01/30/2023]
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