1
|
Rajewski BH, Makwana KM, Angera IJ, Geremia DK, Zepeda AR, Hallinan GI, Vidal R, Ghetti B, Serrano AL, Del Valle JR. β-Bracelets: Macrocyclic Cross-β Epitope Mimics Based on a Tau Conformational Strain. J Am Chem Soc 2023; 145:23131-23142. [PMID: 37844142 PMCID: PMC10823581 DOI: 10.1021/jacs.3c06830] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2023]
Abstract
The aggregation of misfolded tau into neurotoxic fibrils is linked to the progression of Alzheimer's disease (AD) and related tauopathies. Disease-associated conformations of filamentous tau are characterized by hydrophobic interactions between side chains on unique and distant β-strand modules within each protomer. Here, we report the design and diversity-oriented synthesis of β-arch peptide macrocycles composed of the aggregation-prone PHF6 hexapeptide of tau and the cross-β module specific to the AD tau fold. Termed "β-bracelets", these proteomimetics assemble in a sequence- and macrocycle-dependent fashion, resulting in amyloid-like fibrils that feature in-register parallel β-sheet structure. Backbone N-amination of a selected β-bracelet affords soluble inhibitors of tau aggregation. We further demonstrate that the N-aminated macrocycles block the prion-like cellular seeding activity of recombinant tau as well as mature fibrils from AD patient extracts. These studies establish β-bracelets as a new class of cross-β epitope mimics and demonstrate their utility in the rational design of molecules targeting amyloid propagation and seeding.
Collapse
Affiliation(s)
- Benjamin H. Rajewski
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Kamlesh M. Makwana
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Isaac J. Angera
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Danielle K. Geremia
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Anna R. Zepeda
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Grace I. Hallinan
- Department of Pathology & Laboratory Medicine and Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana, 46202, United States
| | - Ruben Vidal
- Department of Pathology & Laboratory Medicine and Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana, 46202, United States
| | - Bernardino Ghetti
- Department of Pathology & Laboratory Medicine and Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, Indiana, 46202, United States
| | - Arnaldo L. Serrano
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Juan R. Del Valle
- Department of Chemistry & Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, United States
| |
Collapse
|
2
|
Hsueh SCC, Aina A, Roman AY, Cashman NR, Peng X, Plotkin SS. Optimizing Epitope Conformational Ensembles Using α-Synuclein Cyclic Peptide "Glycindel" Scaffolds: A Customized Immunogen Method for Generating Oligomer-Selective Antibodies for Parkinson's Disease. ACS Chem Neurosci 2022; 13:2261-2280. [PMID: 35840132 DOI: 10.1021/acschemneuro.1c00567] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Effectively presenting epitopes on immunogens, in order to raise conformationally selective antibodies through active immunization, is a central problem in treating protein misfolding diseases, particularly neurodegenerative diseases such as Alzheimer's disease or Parkinson's disease. We seek to selectively target conformations enriched in toxic, oligomeric propagating species while sparing the healthy forms of the protein that are often more abundant. To this end, we computationally modeled scaffolded epitopes in cyclic peptides by inserting/deleting a variable number of flanking glycines ("glycindels") to best mimic a misfolding-specific conformation of an epitope of α-synuclein enriched in the oligomer ensemble, as characterized by a region most readily disordered and solvent-exposed in a stressed, partially denatured protofibril. We screen and rank the cyclic peptide scaffolds of α-synuclein in silico based on their ensemble overlap properties with the fibril, oligomer-model and isolated monomer ensembles. We present experimental data of seeded aggregation that support nucleation rates consistent with computationally predicted cyclic peptide conformational similarity. We also introduce a method for screening against structured off-pathway targets in the human proteome by selecting scaffolds with minimal conformational similarity between their epitope and the same solvent-exposed primary sequence in structured human proteins. Different cyclic peptide scaffolds with variable numbers of glycines are predicted computationally to have markedly different conformational ensembles. Ensemble comparison and overlap were quantified by the Jensen-Shannon divergence and a new measure introduced here, the embedding depth, which determines the extent to which a given ensemble is subsumed by another ensemble and which may be a more useful measure in developing immunogens that confer conformational selectivity to an antibody.
Collapse
Affiliation(s)
- Shawn C C Hsueh
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Adekunle Aina
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Andrei Yu Roman
- Djavad Mowafaghian Centre for Brain Health, The University of British Columbia, Vancouver, BC V6T 2B5, Canada
| | - Neil R Cashman
- Djavad Mowafaghian Centre for Brain Health, The University of British Columbia, Vancouver, BC V6T 2B5, Canada
| | - Xubiao Peng
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| | - Steven S Plotkin
- Department of Physics and Astronomy, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada.,Genome Science and Technology Program, The University of British Columbia, Vancouver, BC V6T 1Z1, Canada
| |
Collapse
|
3
|
Oberman K, Gouweleeuw L, Hoogerhout P, Eisel ULM, van Riet E, Schoemaker RG. Vaccination Prevented Short-Term Memory Loss, but Deteriorated Long-Term Spatial Memory in Alzheimer's Disease Mice, Independent of Amyloid-β Pathology. J Alzheimers Dis Rep 2020; 4:261-280. [PMID: 32904788 PMCID: PMC7458552 DOI: 10.3233/adr-200213] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Background: Soluble oligomeric amyloid-β (Aβ), rather than Aβ plaques, seems to be the culprit in Alzheimer’s disease (AD). Accordingly, a new concept vaccine of small cyclic peptide conjugates, selectively targeting oligomeric Aβ, has been developed. Objective: Study the therapeutic potential of this new vaccine in a mouse model for AD. Methods: J20 mice, overexpressing human amyloid precursor protein, were validated for an AD-like phenotype. Then, J20 mice were vaccinated at 2, 3, and 4 months of age and AD phenotype was evaluated at 6, 9, and 12 months of age; or at 9, 10, and 11 months with evaluation at 12 months. Effects on Aβ pathology were studied by plaque load (immunohistochemistry; 6E10) and antibody titers against Aβ (ELISA). AD behavioral phenotype was evaluated by performance in a battery of cognitive tests. Results: J20 mice displayed age-related Aβ plaque development and an AD-like behavioral phenotype. A consistent antibody response to the cyclic peptides was, however, not extended to Aβ, leaving plaque load unaffected. Nevertheless, immunization at young ages prevented working- and short-term spatial memory loss, but deteriorated long-term spatial learning and memory, at 12 months of age. Immunization at later ages did not affect any measured parameter. Conclusion: J20 mice provide a relevant model for AD to study potential anti-Aβ treatment. Early vaccination prevented short-term memory loss at later ages, but deteriorated long-term spatial memory, however without affecting Aβ pathology. Later vaccination had no effects, but optimal timing may require further investigation.
Collapse
Affiliation(s)
- Klaske Oberman
- Department of Neurobiology GELIFES, University Groningen, The Netherlands
| | - Leonie Gouweleeuw
- Department of Neurobiology GELIFES, University Groningen, The Netherlands
| | | | - Ulrich L M Eisel
- Department of Neurobiology GELIFES, University Groningen, The Netherlands
| | | | - Regien G Schoemaker
- Department of Neurobiology GELIFES, University Groningen, The Netherlands.,University Medical Center Groningen, The Netherlands
| |
Collapse
|
4
|
Mulder CK, Dong Y, Brugghe HF, Timmermans HAM, Tilstra W, Westdijk J, van Riet E, van Steeg H, Hoogerhout P, Eisel ULM. Immunization with Small Amyloid-β-derived Cyclopeptide Conjugates Diminishes Amyloid-β-Induced Neurodegeneration in Mice. J Alzheimers Dis 2017; 52:1111-23. [PMID: 27060957 PMCID: PMC4927839 DOI: 10.3233/jad-151136] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Background: Soluble oligomeric (misfolded) species of amyloid-β (Aβ) are the main mediators of toxicity in Alzheimer’s disease (AD). These oligomers subsequently form aggregates of insoluble fibrils that precipitate as extracellular and perivascular plaques in the brain. Active immunization against Aβ is a promising disease modifying strategy. However, eliciting an immune response against Aβ in general may interfere with its biological function and was shown to cause unwanted side-effects. Therefore, we have developed a novel experimental vaccine based on conformational neo-epitopes that are exposed in the misfolded oligomeric Aβ, inducing a specific antibody response. Objective: Here we investigate the protective effects of the experimental vaccine against oligomeric Aβ1-42-induced neuronal fiber loss in vivo. Methods: C57BL/6 mice were immunized or mock-immunized. Antibody responses were measured by enzyme-linked immunosorbent assay. Next, mice received a stereotactic injection of oligomeric Aβ1-42 into the nucleus basalis of Meynert (NBM) on one side of the brain (lesion side), and scrambled Aβ1-42 peptide in the contralateral NBM (control side). The densities of choline acetyltransferase-stained cholinergic fibers origination from the NBM were measured in the parietal neocortex postmortem. The percentage of fiber loss in the lesion side was determined relative to the control side of the brain. Results: Immunized responders (79%) showed 23% less cholinergic fiber loss (p = 0.01) relative to mock-immunized mice. Moreover, fiber loss in immunized responders correlated negatively with the measured antibody responses (R2 = 0.29, p = 0.02). Conclusion: These results may provide a lead towards a (prophylactic) vaccine to prevent or at least attenuate (early onset) AD symptoms.
Collapse
Affiliation(s)
- Cornelis K Mulder
- University of Groningen, Groningen Institute of Evolutionary Life Sciences, Groningen, The Netherlands
| | - Yun Dong
- University of Groningen, Groningen Institute of Evolutionary Life Sciences, Groningen, The Netherlands
| | - Humphrey F Brugghe
- Institute for Translational Vaccinology (Intravacc), Bilthoven, The Netherlands
| | - Hans A M Timmermans
- Institute for Translational Vaccinology (Intravacc), Bilthoven, The Netherlands
| | - Wichard Tilstra
- Institute for Translational Vaccinology (Intravacc), Bilthoven, The Netherlands
| | - Janny Westdijk
- Institute for Translational Vaccinology (Intravacc), Bilthoven, The Netherlands
| | - Elly van Riet
- Institute for Translational Vaccinology (Intravacc), Bilthoven, The Netherlands
| | - Harry van Steeg
- National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands
| | - Peter Hoogerhout
- Institute for Translational Vaccinology (Intravacc), Bilthoven, The Netherlands
| | - Ulrich L M Eisel
- University of Groningen, Groningen Institute of Evolutionary Life Sciences, Groningen, The Netherlands
| |
Collapse
|
5
|
Ziehm T, Brener O, van Groen T, Kadish I, Frenzel D, Tusche M, Kutzsche J, Reiß K, Gremer L, Nagel-Steger L, Willbold D. Increase of Positive Net Charge and Conformational Rigidity Enhances the Efficacy of d-Enantiomeric Peptides Designed to Eliminate Cytotoxic Aβ Species. ACS Chem Neurosci 2016; 7:1088-96. [PMID: 27240424 DOI: 10.1021/acschemneuro.6b00047] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disorder and the most common type of dementia. Until now, there is no curative therapy available. Previously, we selected the amyloid-beta (Aβ) targeting peptide D3 consisting of 12 d-enantiomeric amino acid residues by mirror image phage display as a potential drug candidate for the treatment of AD. In the current approach, we investigated the optimization potential of linear D3 with free C-terminus (D3COOH) by chemical modifications. First, the impact of the net charge was investigated and second, cyclization was introduced which is a well-known tool for the optimization of peptides for enhanced target affinity. Following this strategy, three D3 derivatives in addition to D3COOH were designed: C-terminally amidated linear D3 (D3CONH2), cyclic D3 (cD3), and cyclic D3 with an additional arginine residue (cD3r) to maintain the net charge of linear D3CONH2. These four compounds were compared to each other according to their binding affinities to Aβ(1-42), their efficacy to eliminate cytotoxic oligomers, and consequently their potency to neutralize Aβ(1-42) oligomer induced neurotoxicity. D3CONH2 and cD3r versions with equally increased net charge showed superior properties over D3COOH and cD3, respectively. The cyclic versions showed superior properties compared to their linear version with equal net charge, suggesting cD3r to be the most efficient compound among these four. Indeed, treatment of the transgenic AD mouse model Tg-SwDI with cD3r significantly enhanced spatial memory and cognition of these animals as revealed by water maze performance. Therefore, charge increase and cyclization imply suitable modification steps for an optimization approach of the Aβ targeting compound D3.
Collapse
Affiliation(s)
- Tamar Ziehm
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Oleksandr Brener
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Thomas van Groen
- Department of Cell, Developmental and Integrative
Biology, University of Alabama at Birmingham (UAB), Birmingham, Alabama 35233, United States
| | - Inga Kadish
- Department of Cell, Developmental and Integrative
Biology, University of Alabama at Birmingham (UAB), Birmingham, Alabama 35233, United States
| | - Daniel Frenzel
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Markus Tusche
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Janine Kutzsche
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Kerstin Reiß
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Lothar Gremer
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Luitgard Nagel-Steger
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Dieter Willbold
- Institute of Complex
Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| |
Collapse
|
6
|
Marciani DJ. A retrospective analysis of the Alzheimer's disease vaccine progress - The critical need for new development strategies. J Neurochem 2016; 137:687-700. [PMID: 26990863 DOI: 10.1111/jnc.13608] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 02/25/2016] [Accepted: 02/26/2016] [Indexed: 12/16/2022]
Abstract
The promising results obtained with aducanumab and solanezumab against Alzheimer's disease (AD) strengthen the vaccine approach to prevent AD, despite of the many clinical setbacks. It has been problematic to use conjugated peptides with Th1/Th2 adjuvants to induce immune responses against conformational epitopes formed by Aβ oligomers, which is critical to induce protective antibodies. Hence, vaccination should mimic natural immunity by using whole or if possible conjugated antigens, but biasing the response to Th2 with anti-inflammatory adjuvants. Also, selection of the carrier and cross-linking agents is important to prevent suppression of the immune response against the antigen. That certain compounds having phosphorylcholine or fucose induce a sole Th2 immunity would allow antigens with T-cell epitopes without inflammatory autoimmune reactions to be used. Another immunization method is DNA vaccines combined with antigenic ones, which favors the clonal selection and expansion of high affinity antibodies needed for immune protection, but this also requires Th2 immunity. Since AD transgenic mouse models have limited value for immunogen selection as shown by the clinical studies, screening may require the use of validated antibodies and biophysical methods to identify the antigens that would be most likely recognized by the human immune system and thus capable to stimulate a protective antibody response. To induce an anti-Alzheimer's disease protective immunity and prevent possible damage triggered by antigens having B-cell epitopes-only, whole antigens might be used; while inducing Th2 immunity with sole anti-inflammatory fucose-based adjuvants. This approach would avert a damaging systemic inflammatory immunity and the suppression of immunoresponse against the antigen because of carrier and cross-linkers; immune requirements that extend to DNA vaccines.
Collapse
|
7
|
Andreasen M, Lorenzen N, Otzen D. Interactions between misfolded protein oligomers and membranes: A central topic in neurodegenerative diseases? BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2015; 1848:1897-907. [PMID: 25666871 DOI: 10.1016/j.bbamem.2015.01.018] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/26/2015] [Accepted: 01/29/2015] [Indexed: 11/19/2022]
Abstract
The deposition of amyloid material has been associated with many different diseases. Although these diseases are very diverse the amyloid material share many common features such as cross-β-sheet structure of the backbone of the proteins deposited. Another common feature of the aggregation process for a wide variety of proteins is the presence of prefibrillar oligomers. These oligomers are linked to the cytotoxicity occurring during the aggregation of proteins. These prefibrillar oligomers interact extensively with lipid membranes and in some cases leads to destabilization of lipid membranes. This interaction is however highly dependent on the nature of both the oligomer and the lipids. Anionic lipids are often required for interaction with the lipid membrane while increased exposure of hydrophobic patches from highly dynamic protein oligomers are structural determinants of cytotoxicity of the oligomers. To explore the oligomer lipid interaction in detail the interaction between oligomers of α-synuclein and the 4th fasciclin-1 domain of TGFBIp with lipid membranes will be examined here. For both proteins the dynamic species are the ones causing membrane destabilization and the membrane interaction is primarily seen when the lipid membranes contain anionic lipids. Hence the dynamic nature of oligomers with exposed hydrophobic patches alongside the presence of anionic lipids could be essential for the cytotoxicity observed for prefibrillar oligomers in general. This article is part of a Special Issue entitled: Lipid-protein interactions.
Collapse
Affiliation(s)
- Maria Andreasen
- Department of Chemistry, Cambridge University, Lensfield Road, Cambridge CB2 1EW, UK; Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK 8000 Aarhus C, Denmark
| | - Nikolai Lorenzen
- Department of Protein Biophysics and Formulation, Biopharmaceuticals Research Unit, Novo Nordisk A/S, 2760 Måløv, Denmark
| | - Daniel Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, DK 8000 Aarhus C, Denmark.
| |
Collapse
|
8
|
Yu YZ, Wang S, Bai JY, Zhao M, Chen A, Wang WB, Chang Q, Liu S, Qiu WY, Pang XB, Xu Q, Sun ZW. Effective DNA epitope chimeric vaccines for Alzheimer's disease using a toxin-derived carrier protein as a molecular adjuvant. Clin Immunol 2013; 149:11-24. [DOI: 10.1016/j.clim.2013.05.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 04/30/2013] [Accepted: 05/25/2013] [Indexed: 10/26/2022]
|
9
|
Barber CJS, Pujara PT, Reed DW, Chiwocha S, Zhang H, Covello PS. The two-step biosynthesis of cyclic peptides from linear precursors in a member of the plant family Caryophyllaceae involves cyclization by a serine protease-like enzyme. J Biol Chem 2013; 288:12500-10. [PMID: 23486480 DOI: 10.1074/jbc.m112.437947] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Caryophyllaceae-type cyclic peptides (CPs) of 5-12 proteinogenic amino acids occur in 10 plant families. In Saponaria vaccaria (Caryophyllaceae), they have been shown to be formed from linear peptide precursors derived from ribosomal translation. There is also evidence for such precursors in other members of the Caryophyllaceae, Rutaceae, and Linaceae families. The biosynthesis of CP in the developing seeds of S. vaccaria was investigated with respect to the enzymes involved in precursor processing. Through biochemical assays with seed extracts and synthetic peptides, an enzyme named oligopeptidase 1 (OLP1) was found that catalyzes the cleavage of intermediates at the N terminus of the incipient CP. A second enzyme, peptide cyclase 1 (PCY1), which was separated chromatographically from OLP1, was found to act on the product of OLP1, giving rise to a cyclic peptide and concomitant removal of a C-terminal flanking sequence. PCY1 was partially purified, and using the methods of proteomics, a full-length cDNA clone encoding an enzyme matching the properties of PCY1 was obtained. The substrate specificity of purified recombinant PCY1, believed to be the first cloned plant enzyme whose function is peptide cyclization, was tested with synthetic peptides. The results are discussed in the light of CP biosynthetic systems of other organisms.
Collapse
Affiliation(s)
- Carla J S Barber
- National Research Council of Canada, Saskatoon, Saskatchewan S7N 0W9, Canada
| | | | | | | | | | | |
Collapse
|
10
|
Aravinda S, Raghavender US, Rai R, Harini VV, Shamala N, Balaram P. Analysis of designed β-hairpin peptides: molecular conformation and packing in crystals. Org Biomol Chem 2013; 11:4220-31. [DOI: 10.1039/c3ob25777k] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|