1
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Ganguly HK, Basu G. Conformational landscape of substituted prolines. Biophys Rev 2020; 12:25-39. [PMID: 31953795 PMCID: PMC7040156 DOI: 10.1007/s12551-020-00621-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 01/09/2020] [Indexed: 12/16/2022] Open
Abstract
The cyclic side chain of the amino acid proline confers unique conformational restraints on its backbone and side chain dihedral angles. This affects two equilibria-one at the backbone (cis/trans) and the other at the side chain (endo/exo). Substitutions on the proline ring impose additional steric and stereoelectronic effects that can further modulate both these equilibria, which in turn can also affect the backbone dihedral angle (ϕ, ψ) preferences. In this review, we have explored the conformational landscape of several termini capped mono-(2-, 3-, 4-, and 5-) substituted proline derivatives in the Cambridge Structural Database, correlating observed conformations with the nature of substituents and deciphering the underlying interactions for the observed structural biases. The impact of incorporating these derivatives within model peptides and proteins are also discussed for selected cases. Several of these substituents have been used to introduce bioorthogonal functionality and modulate structure-specific ligand recognition or used as spectroscopic probes. The incorporation of these diversely applicable functional groups, coupled with their ability to define an amino acid conformation via stereoelectronic effects, have a broad appeal among chemical biologists, molecular biophysicists, and medicinal chemists.
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Affiliation(s)
- Himal Kanti Ganguly
- Department of Biophysics, Bose Institute, P-1/12 CIT scheme VII M, Kolkata, 700054, India.
| | - Gautam Basu
- Department of Biophysics, Bose Institute, P-1/12 CIT scheme VII M, Kolkata, 700054, India.
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Dongmo Foumthuim CJ, Corazza A, Esposito G, Fogolari F. Molecular dynamics simulations of β2-microglobulin interaction with hydrophobic surfaces. MOLECULAR BIOSYSTEMS 2018; 13:2625-2637. [PMID: 29051937 DOI: 10.1039/c7mb00464h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Hydrophobic surfaces are known to adsorb and unfold proteins, a process that has been studied only for a few proteins. Here we address the interaction of β2-microglobulin, a paradigmatic protein for the study of amyloidogenesis, with hydrophobic surfaces. A system with 27 copies of the protein surrounded by a model cubic hydrophobic box is studied by implicit solvent molecular dynamics simulations. Most proteins adsorb on the walls of the box without major distortions in local geometry, whereas free molecules maintain proper structures and fluctuations as observed in explicit solvent molecular dynamics simulations. The major conclusions from the simulations are as follows: (i) the adopted implicit solvent model is adequate to describe protein dynamics and thermodynamics; (ii) adsorption occurs readily and is irreversible on the simulated timescale; (iii) the regions most involved in molecular encounters and stable interactions with the walls are the same as those that are important in protein-protein and protein-nanoparticle interactions; (iv) unfolding following adsorption occurs at regions found to be flexible by both experiments and simulations; (v) thermodynamic analysis suggests a very large contribution from van der Waals interactions, whereas unfavorable electrostatic interactions are not found to contribute much to adsorption energy. Surfaces with different degrees of hydrophobicity may occur in vivo. Our simulations show that adsorption is a fast and irreversible process which is accompanied by partial unfolding. The results and the thermodynamic analysis presented here are consistent with and rationalize previous experimental work.
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3
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Barbiroli A, Marengo M, Fessas D, Ragg E, Renzetti S, Bonomi F, Iametti S. Stabilization of beta-lactoglobulin by polyols and sugars against temperature-induced denaturation involves diverse and specific structural regions of the protein. Food Chem 2017; 234:155-162. [DOI: 10.1016/j.foodchem.2017.04.132] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/13/2017] [Accepted: 04/20/2017] [Indexed: 01/10/2023]
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4
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Narang SS, Shuaib S, Goyal D, Goyal B. Assessing the effect of D59P mutation in the DE loop region in amyloid aggregation propensity of β2‐microglobulin: A molecular dynamics simulation study. J Cell Biochem 2017; 119:782-792. [DOI: 10.1002/jcb.26241] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 06/27/2017] [Indexed: 02/06/2023]
Affiliation(s)
- Simranjeet S. Narang
- Department of Chemistry School of Basic and Applied Sciences Sri Guru Granth Sahib World University Punjab India
| | - Suniba Shuaib
- Department of Chemistry School of Basic and Applied Sciences Sri Guru Granth Sahib World University Punjab India
| | - Deepti Goyal
- Department of Chemistry School of Basic and Applied Sciences Sri Guru Granth Sahib World University Punjab India
| | - Bhupesh Goyal
- Department of Chemistry School of Basic and Applied Sciences Sri Guru Granth Sahib World University Punjab India
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5
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Borotto NB, Zhang Z, Dong J, Burant B, Vachet RW. Increased β-Sheet Dynamics and D-E Loop Repositioning Are Necessary for Cu(II)-Induced Amyloid Formation by β-2-Microglobulin. Biochemistry 2017; 56:1095-1104. [PMID: 28168880 DOI: 10.1021/acs.biochem.6b01198] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
β-2-Microglobulin (β2m) forms amyloid fibrils in the joints of patients undergoing dialysis treatment as a result of kidney failure. One of the ways in which β2m can be induced to form amyloid fibrils in vitro is via incubation with stoichiometric amounts of Cu(II). To better understand the structural changes caused by Cu(II) binding that allow β2m to form amyloid fibrils, we compared the effect of Ni(II) and Zn(II) binding, which are two similarly sized divalent metal ions that do not induce β2m amyloid formation. Using hydrogen/deuterium exchange mass spectrometry (HDX/MS) and covalent labeling MS, we find that Ni(II) has little effect on β2m structure, despite binding in the same region of the protein as Cu(II). This observation indicates that subtle differences in the organization of residues around Cu(II) cause distant changes that are necessary for oligomerization and eventual amyloid formation. One key difference that we find is that only Cu(II), not Ni(II) or Zn(II), is able to cause the cis-trans isomerization of Pro32 that is an important conformational switch that initiates β2m amyloid formation. By comparing HDX/MS data from the three metal-β2m complexes, we also discover that increased dynamics in the β-sheet formed by the A, B, D, and E β strands of the protein and repositioning of residues in the D-E loop are necessary aspects of β2m forming an amyloid-competent dimer. Altogether, our results reveal new structural insights into the unique effect of Cu(II) in the metal-induced amyloid formation of β2m.
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Affiliation(s)
- Nicholas B Borotto
- Department of Chemistry, University of Massachusetts Amherst , Amherst, Massachusetts 01003, United States
| | - Zhe Zhang
- Department of Chemistry, University of Massachusetts Amherst , Amherst, Massachusetts 01003, United States
| | - Jia Dong
- Department of Chemistry, University of Massachusetts Amherst , Amherst, Massachusetts 01003, United States
| | - Brittney Burant
- Department of Chemistry, University of Massachusetts Amherst , Amherst, Massachusetts 01003, United States
| | - Richard W Vachet
- Department of Chemistry, University of Massachusetts Amherst , Amherst, Massachusetts 01003, United States
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6
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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] [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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7
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Zang T, Broszczak DA, Broadbent JA, Cuttle L, Lu H, Parker TJ. The biochemistry of blister fluid from pediatric burn injuries: proteomics and metabolomics aspects. Expert Rev Proteomics 2015; 13:35-53. [PMID: 26581649 DOI: 10.1586/14789450.2016.1122528] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Burn injury is a prevalent and traumatic event for pediatric patients. At present, the diagnosis of burn injury severity is subjective and lacks a clinically relevant quantitative measure. This is due in part to a lack of knowledge surrounding the biochemistry of burn injuries and that of blister fluid. A more complete understanding of the blister fluid biochemistry may open new avenues for diagnostic and prognostic development. Burn insult induces a highly complex network of signaling processes and numerous changes within various biochemical systems, which can ultimately be examined using proteome and metabolome measurements. This review reports on the current understanding of burn wound biochemistry and outlines a technical approach for 'omics' profiling of blister fluid from burn wounds of differing severity.
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Affiliation(s)
- Tuo Zang
- a Tissue Repair and Regeneration Program , Institute of Health and Biomedical Innovation , Kelvin Grove , Australia.,b School of Biomedical Sciences , Queensland University of Technology , Brisbane , Australia.,c Wound Management Innovation Co-operative Research Centre , West End , Australia
| | - Daniel A Broszczak
- a Tissue Repair and Regeneration Program , Institute of Health and Biomedical Innovation , Kelvin Grove , Australia.,b School of Biomedical Sciences , Queensland University of Technology , Brisbane , Australia.,c Wound Management Innovation Co-operative Research Centre , West End , Australia
| | - James A Broadbent
- a Tissue Repair and Regeneration Program , Institute of Health and Biomedical Innovation , Kelvin Grove , Australia.,b School of Biomedical Sciences , Queensland University of Technology , Brisbane , Australia.,c Wound Management Innovation Co-operative Research Centre , West End , Australia
| | - Leila Cuttle
- a Tissue Repair and Regeneration Program , Institute of Health and Biomedical Innovation , Kelvin Grove , Australia.,b School of Biomedical Sciences , Queensland University of Technology , Brisbane , Australia.,d Centre for Children's Burns and Trauma Research , Queensland University of Technology, Institute of Health and Biomedical Innovation at the Centre for Children's Health Research , South Brisbane , Australia
| | - Haitao Lu
- a Tissue Repair and Regeneration Program , Institute of Health and Biomedical Innovation , Kelvin Grove , Australia.,b School of Biomedical Sciences , Queensland University of Technology , Brisbane , Australia
| | - Tony J Parker
- a Tissue Repair and Regeneration Program , Institute of Health and Biomedical Innovation , Kelvin Grove , Australia.,b School of Biomedical Sciences , Queensland University of Technology , Brisbane , Australia
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8
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De Genst E, Messer A, Dobson CM. Antibodies and protein misfolding: From structural research tools to therapeutic strategies. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:1907-1919. [PMID: 25194824 DOI: 10.1016/j.bbapap.2014.08.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 08/21/2014] [Accepted: 08/27/2014] [Indexed: 01/24/2023]
Abstract
Protein misfolding disorders, including the neurodegenerative conditions Alzheimer's disease (AD) and Parkinson's disease (PD) represent one of the major medical challenges or our time. The underlying molecular mechanisms that govern protein misfolding and its links with disease are very complex processes, involving the formation of transiently populated but highly toxic molecular species within the crowded environment of the cell and tissue. Nevertheless, much progress has been made in understanding these events in recent years through innovative experiments and therapeutic strategies, and in this review we present an overview of the key roles of antibodies and antibody fragments in these endeavors. We discuss in particular how these species are being used in combination with a variety of powerful biochemical and biophysical methodologies, including a range of spectroscopic and microscopic techniques applied not just in vitro but also in situ and in vivo, both to gain a better understanding of the mechanistic nature of protein misfolding and aggregation and also to design novel therapeutic strategies to combat the family of diseases with which they are associated. This article is part of a Special Issue entitled: Recent advances in molecular engineering of antibody.
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Affiliation(s)
- Erwin De Genst
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
| | - Anne Messer
- Neural Stem Cell Institute, Regenerative Research Foundation, Rensselaer, NY 12144, USA; Department of Biomedical Sciences, University at Albany, Albany, NY 12208, USA
| | - Christopher M Dobson
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
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9
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Leney AC, Pashley CL, Scarff CA, Radford SE, Ashcroft AE. Insights into the role of the beta-2 microglobulin D-strand in amyloid propensity revealed by mass spectrometry. MOLECULAR BIOSYSTEMS 2013; 10:412-20. [PMID: 24336936 PMCID: PMC4006425 DOI: 10.1039/c3mb70420c] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Characterising the differences between oligomers formed from the amyloidogenic protein β2-microglobulin and its mutant H51A using ESI-IMS-MS.
In vivo beta-2 microglobulin (β2m) forms amyloid fibrils that are associated with the disease dialysis-related amyloidosis. Here, electrospray ionisation-ion mobility spectrometry-mass spectrometry has been used to compare the oligomers formed from wild-type β2m with those formed from a variant of the protein containing a single point mutation in the D strand, H51A, during in vitro fibril assembly. Using the amyloid-binding fluorescent dye, Thioflavin T, to monitor fibrillation kinetics, H51A was shown to exhibit a two-fold increase in the lag-time of fibril formation. Despite this, comparison of the oligomeric species observed during the lag-time of self-aggregation indicated that H51A had a higher population of oligomers, and formed oligomers of higher order, than wild-type β2m. The cross-sectional areas of the oligomers arising from H51A and wild-type protein were indistinguishable, although the H51A oligomers were shown to have a significantly higher kinetic stability on account of their reluctance to undergo sub-unit exchange when mixed with 15N-labelled protein. Together the data reveal a significant effect of His51, and thus that of the D-strand sequence, on amyloid formation. The results also highlight the power of mass spectrometry in probing complex biochemical mechanisms in real-time.
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Affiliation(s)
- Aneika C Leney
- Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK.
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10
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Craveur P, Joseph AP, Rebehmed J, de Brevern AG. β-Bulges: extensive structural analyses of β-sheets irregularities. Protein Sci 2013; 22:1366-78. [PMID: 23904395 DOI: 10.1002/pro.2324] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 07/19/2013] [Accepted: 07/22/2013] [Indexed: 12/30/2022]
Abstract
β-Sheets are quite frequent in protein structures and are stabilized by regular main-chain hydrogen bond patterns. Irregularities in β-sheets, named β-bulges, are distorted regions between two consecutive hydrogen bonds. They disrupt the classical alternation of side chain direction and can alter the directionality of β-strands. They are implicated in protein-protein interactions and are introduced to avoid β-strand aggregation. Five different types of β-bulges are defined. Previous studies on β-bulges were performed on a limited number of protein structures or one specific family. These studies evoked a potential conservation during evolution. In this work, we analyze the β-bulge distribution and conservation in terms of local backbone conformations and amino acid composition. Our dataset consists of 66 times more β-bulges than the last systematic study (Chan et al. Protein Science 1993, 2:1574-1590). Novel amino acid preferences are underlined and local structure conformations are highlighted by the use of a structural alphabet. We observed that β-bulges are preferably localized at the N- and C-termini of β-strands, but contrary to the earlier studies, no significant conservation of β-bulges was observed among structural homologues. Displacement of β-bulges along the sequence was also investigated by Molecular Dynamics simulations.
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Affiliation(s)
- Pierrick Craveur
- INSERM, U665, DSIMB, F-75739, Paris, France; University of Paris Diderot, Sorbonne Paris Cité, UMR_S 665, F-75739, Paris, France; Institut National de la Transfusion Sanguine (INTS), F-75739, Paris, France; Laboratoire d'Excellence GR-Ex, F-75739, Paris, France
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11
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Abstract
The deposition of peptides and proteins as amyloid fibrils is a common feature of nearly 50 medical -disorders affecting the brain or a variety of other organs and tissues. These disorders, which include Alzheimer's disease, Parkinson's disease, the prion diseases, and type II diabetes, have an enormous impact on the public health and economy of the modern world. Extensive research is therefore taking place to determine the underlying molecular mechanisms and determinants of the pathological conversion of amyloidogenic proteins from their soluble forms into fibrillar structures. The use of molecular probes and biophysical techniques, such as X-ray crystallography and particularly NMR spectroscopy, are allowing detailed analysis of the mechanism of fibril formation and of the underlying structural and chemical features of the associated pathogenicity. Nanobodies, the antigen-binding domains derived from camelid heavy-chain antibodies, are excellent tools to probe protein aggregation as a result of their exquisite specificity and high affinity and stability, along with their ease of expression and small size; the latter in particular allows them to be used very efficiently in combination with NMR spectroscopy and X-ray crystallography. In this chapter we present an overview of how nanobodies are being used to obtain detailed information on the mechanisms of amyloid formation and on the nature and origin of their links with human diseases.
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Affiliation(s)
- Erwin De Genst
- Department of Chemistry, University of Cambridge, Cambridge, UK.
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12
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Ami D, Ricagno S, Bolognesi M, Bellotti V, Doglia SM, Natalello A. Structure, stability, and aggregation of β-2 microglobulin mutants: insights from a Fourier transform infrared study in solution and in the crystalline state. Biophys J 2012; 102:1676-84. [PMID: 22500768 DOI: 10.1016/j.bpj.2012.02.045] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2011] [Revised: 02/17/2012] [Accepted: 02/21/2012] [Indexed: 10/28/2022] Open
Abstract
β-2 microglobulin (β2m) is an amyloidogenic protein involved in dialysis-related amyloidosis. We report here the study of the structural properties of the protein in solution and in the form of single crystals by Fourier transform infrared (FTIR) spectroscopy and microspectroscopy. The investigation has been extended to four β2m mutants previously characterized by x-ray crystallography: Asp(53)Pro, Asp(59)Pro, Trp(60)Gly, and Trp(60)Val. These variants displayed very similar three-dimensional structures but different thermal stability and aggregation propensity, investigated here by FTIR spectroscopy. For each variant, appreciable spectral differences were found between the protein in solution and in single crystals, consisting in a downshift of the main β-sheet band and in better resolved turn and loop bands, indicative of reduced protein secondary structure dynamics in the crystalline state. Notably, the well-resolved spectra of the β2m crystalline variants enabled us to identify structural differences induced by the single amino acid mutations. Such differences encompass turn and loop structures that might affect the stability and aggregation propensity of the investigated β2m variants. This study highlights the potential of FTIR microspectroscopy to acquire useful structural information on protein crystals, complementary to the crystallographic analyses.
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Affiliation(s)
- Diletta Ami
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
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13
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Abstract
Dialysis-related amyloidosis (DRA) is a clinical syndrome of pain, loss of function and other symptoms due to the deposition of amyloid consisting of β(2)-microglobulin (β(2)m) in the musculoskeletal system. The condition is seen in patients who suffer from chronic kidney disease and are treated with hemodialysis for a long time. Even though β(2)m easily can be manipulated to form amyloid in laboratory experiments under non-physiological conditions the precise mechanisms involved in the formation of β(2)m-amyloid in patients with DRA have been difficult to unravel. The current knowledge which is reviewed here indicates that conformational fluctuations centered around the D-strand, the DE-loop, and around the cis-configured Pro32 peptide bond are involved in β(2)m amyloidosis. Also required are highly increased concentrations of circulating β(2)m and possibly various post-translational modifications mediated by the pro-inflammatory environment in uremic blood, together with the influence of divalent metal ions (specifically Cu(2 +)), uremic toxins, and dialysis-enhanced redox-processes. It seems plausible that domain-swapped β(2)m dimers act as building blocks of β-spine cross-β -sheet fibrils consisting of otherwise globular, roughly natively folded protein. An activated complement system and cellular activation perpetuate these reactions which due to the affinity of β(2)m-amyloid for the collagen of synovial surfaces result in the DRA syndrome.
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Affiliation(s)
- Dorthe B Corlin
- Department of Clinical Biochemistry and Immunology, Division of Microbiology and Diagnostics, Statens Serum Institut, Bldg. 85/240, Artillerivej 5, 2300, Copenhagen S, Denmark,
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