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Přáda Brichtová E, Krupová M, Bouř P, Lindo V, Gomes Dos Santos A, Jackson SE. Glucagon-like peptide 1 aggregates into low-molecular-weight oligomers off-pathway to fibrillation. Biophys J 2023; 122:2475-2488. [PMID: 37138517 PMCID: PMC10323027 DOI: 10.1016/j.bpj.2023.04.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 01/04/2023] [Accepted: 04/27/2023] [Indexed: 05/05/2023] Open
Abstract
The physical stability of peptide-based drugs is of great interest to the pharmaceutical industry. Glucagon-like peptide 1 (GLP-1) is a 31-amino acid peptide hormone, the analogs of which are frequently used in the treatment of type 2 diabetes. We investigated the physical stability of GLP-1 and its C-terminal amide derivative, GLP-1-Am, both of which aggregate into amyloid fibrils. While off-pathway oligomers have been proposed to explain the unusual aggregation kinetics observed previously for GLP-1 under specific conditions, these oligomers have not been studied in any detail. Such states are important as they may represent potential sources of cytotoxicity and immunogenicity. Here, we identified and isolated stable, low-molecular-weight oligomers of GLP-1 and GLP-1-Am, using size-exclusion chromatography. Under the conditions studied, isolated oligomers were shown to be resistant to fibrillation or dissociation. These oligomers contain between two and five polypeptide chains and they have a highly disordered structure as indicated by a variety of spectroscopic techniques. They are highly stable with respect to time, temperature, or agitation despite their noncovalent character, which was established using liquid chromatography-mass spectrometry and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These results provide evidence of stable, low-molecular-weight oligomers that are formed by an off-pathway mechanism which competes with amyloid fibril formation.
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Affiliation(s)
- Eva Přáda Brichtová
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
| | - Monika Krupová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague 6, Czech Republic; Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, Tromsø, Norway
| | - Petr Bouř
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague 6, Czech Republic
| | - Viv Lindo
- AstraZeneca, Cambridge, United Kingdom
| | | | - Sophie E Jackson
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom.
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2
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Admane N, Kothandan R, Syed S, Biswas S. A quinoline alkaloid potentially modulates the amyloidogenic structural transitions of the biofilm scaffolding small basic protein. J Biomol Struct Dyn 2023; 41:1366-1377. [PMID: 34963419 DOI: 10.1080/07391102.2021.2020165] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Bacterial biofilm formation by communities of opportunistic bacterial pathogens like Staphylococcus epidermidis is regarded as the primary virulence mechanism facilitating the spread of detrimental nosocomial and implant-associated infections. An 18-kDa small basic protein (Sbp) and its amyloid fibrils account for strengthening the biofilm architecture and scaffolding the S. epidermidis biofilm matrix. Our study reports systematic analysis of the amyloidogenic structural transitions of Sbp and predicts the amyloid core of the protein which may trigger misfolding and aggregation. Herein, we report the novel amyloid inhibitory potential of Camptothecin, a quinoline alkaloid which binds stably to Sbp monomers and redirects the formation of unstructured regions further destabilizing the protein. Molecular dynamics simulations reveal that Camptothecin averts β-sheet transitions, interrupts with electrostatic interactions and disrupts the intermolecular hydrophobic associations between the exposed hydrophobic amyloidogenic regions of Sbp. Collectively, our study puts forward the first report detailing the heteromolecular associations and amyloid modulatory effects of Camptothecin which may serve as a structural scaffold for the tailored designing of novel drugs targeting the S. epidermidis biofilm matrix.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Nikita Admane
- ViStA Lab, Department of Biological Sciences, BITS, Goa, India
| | - Ram Kothandan
- Bioinformatics Laboratory, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, India
| | - Sowfia Syed
- Bioinformatics Laboratory, Department of Biotechnology, Kumaraguru College of Technology, Coimbatore, India
| | - Sumit Biswas
- ViStA Lab, Department of Biological Sciences, BITS, Goa, India
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3
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Zaman M, Andreasen M. Modulating Kinetics of the Amyloid-Like Aggregation of S. aureus Phenol-Soluble Modulins by Changes in pH. Microorganisms 2021; 9:microorganisms9010117. [PMID: 33430169 PMCID: PMC7825627 DOI: 10.3390/microorganisms9010117] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/30/2020] [Accepted: 01/04/2021] [Indexed: 11/26/2022] Open
Abstract
The pathogen Staphylococcus aureus is recognized as one of the most frequent causes of biofilm-associated infections. The recently identified phenol-soluble modulin (PSM) peptides act as the key molecular effectors of staphylococcal biofilm maturation and promote the formation of an aggregated fibril structure. The aim of this study was to evaluate the effect of various pH values on the formation of functional amyloids of individual PSM peptides. Here, we combined a range of biophysical, chemical kinetics and microscopic techniques to address the structure and aggregation mechanism of individual PSMs under different conditions. We established that there is a pH-induced switch in PSM aggregation kinetics. Different lag times and growth of fibrils were observed, which indicates that there was no clear correlation between the rates of fibril elongation among different PSMs. This finding confirms that pH can modulate the aggregation properties of these peptides and suggest a deeper understanding of the formation of aggregates, which represents an important basis for strategies to interfere and might help in reducing the risk of biofilm-related infections.
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Eskandari H, Ghanadian M, Noleto-Dias C, Lomax C, Tawfike A, Christiansen G, Sutherland DS, Ward JL, Mohammad-Beigi H, Otzen DE. Inhibitors of α-Synuclein Fibrillation and Oligomer Toxicity in Rosa damascena: The All-Pervading Powers of Flavonoids and Phenolic Glycosides. ACS Chem Neurosci 2020; 11:3161-3173. [PMID: 32886481 DOI: 10.1021/acschemneuro.0c00528] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
There is an intense search for natural compounds that can inhibit the oligomerization and fibrillation of α-synuclein (α-Syn), whose aggregation is key to the development of Parkinson's disease (PD). Rosa damascena is a medicinal herb widely used in Middle Eastern food, ceremonies, and perfumes. The herb is known to contain many different polyphenols. Here we investigated the existence of α-Syn fibrillation inhibitors in R. damascena extract. Different HPLC fractions of the extract were assessed in α-Syn fibrillation and toxicity assays. The most active fractions led to the formation of more α-Syn oligomers but with less toxicity to SH-SY5Y cells, according to MTT and LDH assays. LC-MS analysis identified gallic acid, kaempferol 3-glucoside, kaempferol-3-O-β-rutinoside, and quercetin which were subsequently shown to be strong α-Syn fibrillation inhibitors. Our results highlight the benefits of R. damascena extract to combat PD at the population level.
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Affiliation(s)
- Hoda Eskandari
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Gustav Wieds Vej 14, DK− 8000 Aarhus C, Denmark
| | - Mustafa Ghanadian
- Department of Pharmacognosy, Isfahan Faculty of Pharmacy, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Clarice Noleto-Dias
- Computational and Analytical Sciences Department, Rothamsted Research, West Common, Harpenden, Herts AL5 2JQ, U.K
| | - Charlotte Lomax
- Computational and Analytical Sciences Department, Rothamsted Research, West Common, Harpenden, Herts AL5 2JQ, U.K
| | - Ahmed Tawfike
- Computational and Analytical Sciences Department, Rothamsted Research, West Common, Harpenden, Herts AL5 2JQ, U.K
| | - Gunna Christiansen
- Department of Biomedicine-Medical Microbiology and Immunology, Aarhus University, 8000 Aarhus C, Denmark
| | - Duncan S. Sutherland
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Gustav Wieds Vej 14, DK− 8000 Aarhus C, Denmark
| | - Jane L. Ward
- Computational and Analytical Sciences Department, Rothamsted Research, West Common, Harpenden, Herts AL5 2JQ, U.K
| | - Hossein Mohammad-Beigi
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Gustav Wieds Vej 14, DK− 8000 Aarhus C, Denmark
| | - Daniel E. Otzen
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Gustav Wieds Vej 14, DK− 8000 Aarhus C, Denmark
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Egbu R, van der Walle CF, Brocchini S, Williams GR. Inhibiting the fibrillation of a GLP-1-like peptide. Int J Pharm 2020; 574:118923. [PMID: 31812799 DOI: 10.1016/j.ijpharm.2019.118923] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 11/28/2019] [Accepted: 11/30/2019] [Indexed: 11/30/2022]
Abstract
Aggregation, including the formation of fibrils, poses significant challenges for the development of therapeutic peptides. To prepare stable peptide formulations, some understanding of the mechanisms underpinning the fibrillation process is required. A thioflavin T fluorescence assay was first used to determine the fibrillation profile of a GLP-1-like peptide (G48) at conditions being considered to formulate the peptide. G48 concentrations ranged from 0 to 600 µM and three pH values (pH 3.7, 7.4 and 8.5) were evaluated. Kinetic data demonstrate that G48 displays a pH-dependent aggregation profile. At pH 3.7, which is below the isoelectric point of G48 (pI ~ 5), kinetics representative of amorphous aggregates forming via a nucleation-independent mechanism were seen. At pH 7.4 and 8.5 (pH > pI) typical nucleation-dependent aggregation kinetics were observed. The weight concentration of β-sheet rich aggregates (FLmax) correlated inversely with net charge, so lower FLmax values were observed at pH 3.7 and 8.5 than at pH 7.4. Incorporation of a non-ionic surfactant (polysorbate 80) into the peptide solution suppressed the fibrillation of G48 at all pH values and maintained the native peptide conformation, whereas a phenolic co-formulant (ferulic acid) had minimal effects on fibril growth. Peptide fibrillation, which can occur within a range of formulation concentrations and pH values, can hence be inhibited by the judicious use of excipients.
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Affiliation(s)
- Raphael Egbu
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| | | | - Steve Brocchini
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Gareth R Williams
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK.
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6
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Achieving cytochrome c fibril/aggregate control towards micro-platelets and micro-fibers by tuning pH and protein concentration: A combined morphological and spectroscopic analysis. Int J Biol Macromol 2019; 138:106-115. [DOI: 10.1016/j.ijbiomac.2019.07.060] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 11/20/2022]
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7
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Bothe JR, Andrews A, Smith KJ, Joyce LA, Krishnamachari Y, Kashi S. Peptide Oligomerization Memory Effects and Their Impact on the Physical Stability of the GLP-1 Agonist Liraglutide. Mol Pharm 2019; 16:2153-2161. [DOI: 10.1021/acs.molpharmaceut.9b00106] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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8
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Hasecke F, Miti T, Perez C, Barton J, Schölzel D, Gremer L, Grüning CSR, Matthews G, Meisl G, Knowles TPJ, Willbold D, Neudecker P, Heise H, Ullah G, Hoyer W, Muschol M. Origin of metastable oligomers and their effects on amyloid fibril self-assembly. Chem Sci 2018; 9:5937-5948. [PMID: 30079208 PMCID: PMC6050532 DOI: 10.1039/c8sc01479e] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 06/12/2018] [Indexed: 01/05/2023] Open
Abstract
Assembly of rigid amyloid fibrils with their characteristic cross-β sheet structure is a molecular signature of numerous neurodegenerative and non-neuropathic disorders. Frequently large populations of small globular amyloid oligomers (gOs) and curvilinear fibrils (CFs) precede the formation of late-stage rigid fibrils (RFs), and have been implicated in amyloid toxicity. Yet our understanding of the origin of these metastable oligomers, their role as on-pathway precursors or off-pathway competitors, and their effects on the self-assembly of amyloid fibrils remains incomplete. Using two unrelated amyloid proteins, amyloid-β and lysozyme, we find that gO/CF formation, analogous to micelle formation by surfactants, is delineated by a "critical oligomer concentration" (COC). Below this COC, fibril assembly replicates the sigmoidal kinetics of nucleated polymerization. Upon crossing the COC, assembly kinetics becomes biphasic with gO/CF formation responsible for the lag-free initial phase, followed by a second upswing dominated by RF nucleation and growth. RF lag periods below the COC, as expected, decrease as a power law in monomer concentration. Surprisingly, the build-up of gO/CFs above the COC causes a progressive increase in RF lag periods. Our results suggest that metastable gO/CFs are off-pathway from RF formation, confined by a condition-dependent COC that is distinct from RF solubility, underlie a transition from sigmoidal to biphasic assembly kinetics and, most importantly, not only compete with RFs for the shared monomeric growth substrate but actively inhibit their nucleation and growth.
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Affiliation(s)
- Filip Hasecke
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
| | - Tatiana Miti
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Carlos Perez
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Jeremy Barton
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Daniel Schölzel
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Lothar Gremer
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Clara S R Grüning
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
| | - Garrett Matthews
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Georg Meisl
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK
| | - Tuomas P J Knowles
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK
| | - Dieter Willbold
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Philipp Neudecker
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Henrike Heise
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Ghanim Ullah
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Wolfgang Hoyer
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Martin Muschol
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
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Nick M, Wu Y, Schmidt NW, Prusiner SB, Stöhr J, DeGrado WF. A long-lived Aβ oligomer resistant to fibrillization. Biopolymers 2018; 109:e23096. [PMID: 29319162 DOI: 10.1002/bip.23096] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 10/16/2017] [Accepted: 10/30/2017] [Indexed: 01/06/2023]
Abstract
The hydrophobic Aβ peptide is highly aggregation prone; it first forms soluble oligomers, which then convert into the amyloid fibrils found in the cerebral plaques of Alzheimer's disease. It is generally understood that as the peptide concentration of Aβ increases, the fibrillization process is accelerated, but we examine the limits on this phenomenon. We found that once a threshold concentration of Aβ is exceeded, a stable oligomer is formed at the expense of fibril formation. The suppression of fibril formation was observed by amyloid-binding dye Thioflavin T and solution nuclear magnetic resonance (NMR). Small-angle X-ray scattering, size exclusion chromatography, and analytical ultracentrifugation demonstrated that Aβ peptides form a range of compact species, with a dimer being an early highly populated oligomer. Solution NMR allowed us to define the secondary structure of this Aβ dimer, which shows interlocking contacts between C-terminal peptide strands. Thus, we present a novel Aβ oligomer that resists conversion to fibrils and remains stable for more than one year.
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Affiliation(s)
- Mimi Nick
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California
| | - Yibing Wu
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California
| | - Nathan W Schmidt
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California
| | - Stanley B Prusiner
- Institute for Neurodegenerative Diseases and Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, California.,Department of Biochemistry and Biophysics, University of California, San Francisco, California
| | - Jan Stöhr
- Institute for Neurodegenerative Diseases and Department of Neurology, Weill Institute for Neurosciences, University of California, San Francisco, California
| | - William F DeGrado
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California
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10
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Zapadka KL, Becher FJ, Gomes Dos Santos AL, Jackson SE. Factors affecting the physical stability (aggregation) of peptide therapeutics. Interface Focus 2017; 7:20170030. [PMID: 29147559 DOI: 10.1098/rsfs.2017.0030] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The number of biological therapeutic agents in the clinic and development pipeline has increased dramatically over the last decade and the number will undoubtedly continue to increase in the coming years. Despite this fact, there are considerable challenges in the development, production and formulation of such biologics particularly with respect to their physical stabilities. There are many cases where self-association to form either amorphous aggregates or highly structured fibrillar species limits their use. Here, we review the numerous factors that influence the physical stability of peptides including both intrinsic and external factors, wherever possible illustrating these with examples that are of therapeutic interest. The effects of sequence, concentration, pH, net charge, excipients, chemical degradation and modification, surfaces and interfaces, and impurities are all discussed. In addition, the effects of physical parameters such as pressure, temperature, agitation and lyophilization are described. We provide an overview of the structures of aggregates formed, as well as our current knowledge of the mechanisms for their formation.
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Affiliation(s)
| | - Frederik J Becher
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | | | - Sophie E Jackson
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
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11
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Zapadka KL, Becher FJ, Uddin S, Varley PG, Bishop S, Gomes Dos Santos AL, Jackson SE. A pH-Induced Switch in Human Glucagon-like Peptide-1 Aggregation Kinetics. J Am Chem Soc 2016; 138:16259-16265. [PMID: 27998088 DOI: 10.1021/jacs.6b05025] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aggregation and amyloid fibril formation of peptides and proteins is a widespread phenomenon. It has serious implications in a range of areas from biotechnological and pharmaceutical applications to medical disorders. The aim of this study was to develop a better understanding of the mechanism of aggregation and amyloid fibrillation of an important pharmaceutical, human glucagon-like peptide-1 (GLP-1). GLP-1 is a 31-residue hormone peptide that plays an important role regulating blood glucose levels, analogues of which are used for treatment of type 2 diabetes. Amyloid fibril formation of GLP-1 was monitored using thioflavin T fluorescence as a function of peptide concentration between pH 7.5 and 8.2. Results from these studies establish that there is a highly unusual pH-induced switch in GLP-1 aggregation kinetics. At pH 8.2, the kinetics are consistent with a nucleation-polymerization mechanism for fibril formation. However, at pH 7.5, highly unusual kinetics are observed, where the lag time increases with increasing peptide concentration. We attribute this result to the formation of off-pathway species together with an initial slow, unimolecular step where monomer converts to a different monomeric form that forms on-pathway oligomers and ultimately fibrils. Estimation of the pKa values of all the ionizable groups in GLP-1 suggest it is the protonation/deprotonation of the N-terminus that is responsible for the switch with pH. In addition, a range of biophysical techniques were used to characterize (1) the start point of the aggregation reaction and (2) the structure and stability of the fibrils formed. These results show that the off-pathway species form under conditions where GLP-1 is most prone to form oligomers.
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Affiliation(s)
- Karolina L Zapadka
- Department of Chemistry, University of Cambridge , Cambridge CB2 1EW, U.K
| | - Frederik J Becher
- Department of Chemistry, University of Cambridge , Cambridge CB2 1EW, U.K
| | - Shahid Uddin
- Formulation Sciences, MedImmune Ltd. , Granta Park, Cambridge CB21 6GH, U.K
| | - Paul G Varley
- Formulation Sciences, MedImmune Ltd. , Granta Park, Cambridge CB21 6GH, U.K
| | - Steve Bishop
- Formulation Sciences, MedImmune , One MedImmune Way, Gaithersburg, Maryland 20878, United States
| | | | - Sophie E Jackson
- Department of Chemistry, University of Cambridge , Cambridge CB2 1EW, U.K
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