1
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Koroleva ON, Kuzmina NV, Dubrovin EV, Drutsa VL. Atomic force microscopy of spherical intermediates on the pathway to fibril formation of influenza A virus nuclear export protein. Microsc Res Tech 2024; 87:1131-1145. [PMID: 38270267 DOI: 10.1002/jemt.24499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/02/2024] [Accepted: 01/07/2024] [Indexed: 01/26/2024]
Abstract
The nuclear export protein of the influenza A virus (NEP) is involved in many important processes of the virus life cycle. This makes it an attractive target for the treatment of a disease caused by a virus. Previously it has been shown, that recombinant variants of NEP are highly prone to aggregation in solution under various conditions with the formation of amyloid-like aggregates. In the present work, the amyloid nature of NEP aggregates was evidenced by Congo red binding assays. Atomic force microscopy has shown that NEP can form two types of spherical nanoparticles, which provide an alternative pathway for the formation of amyloid-like fibrils. Type I of these "fibrillogenic" spheres, formed under physiological conditions, represents the micelle-like particles with height 10-60 nm, which can generate worm-like flexible fibrils with the diameter 2.5-4.0 nm, length 20-500 nm and the Young's modulus ~73 MPa. Type II spherical aggregates with size of about 400-1000 nm, formed at elevated temperatures, includes fractions of drop-like and vesicle-like particles, generating more rigid amyloid-like fibrils with height of ~8 nm, and length of up to 2 μm. The hypothetical mechanism of fibril formation via nanospherical structures was suggested. RESEARCH HIGHLIGHTS: AFM has revealed two types of the influenza A virus nuclear export protein spherical aggregates. They provide an alternative pathway for the formation of amyloid-like fibrils. The mechanism of fibril formation via spherical structures is suggested.
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Affiliation(s)
- Olga N Koroleva
- Faculty of Chemistry, Lomonosov Moscow State University, Moscow, Russian Federation
| | - Natalia V Kuzmina
- Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Moscow, Russian Federation
| | - Evgeniy V Dubrovin
- Faculty of Physics, Lomonosov Moscow State University, Moscow, Russian Federation
- National University of Science and Technology, MISIS, Moscow, Russian Federation
| | - Valeriy L Drutsa
- A.N.Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russian Federation
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2
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Song Y, Lei L, Cai X, Wei H, Yu CY. Immunomodulatory Peptides for Tumor Treatment. Adv Healthc Mater 2024:e2400512. [PMID: 38657003 DOI: 10.1002/adhm.202400512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 04/07/2024] [Indexed: 04/26/2024]
Abstract
Peptides exhibit various biological activities, including biorecognition, cell targeting, and tumor penetration, and can stimulate immune cells to elicit immune responses for tumor immunotherapy. Peptide self-assemblies and peptide-functionalized nanocarriers can reduce the effect of various biological barriers and the degradation by peptidases, enhancing the efficiency of peptide delivery and improving antitumor immune responses. To date, the design and development of peptides with various functionalities have been extensively reviewed for enhanced chemotherapy; however, peptide-mediated tumor immunotherapy using peptides acting on different immune cells, to the knowledge, has not yet been summarized. Thus, this work provides a review of this emerging subject of research, focusing on immunomodulatory anticancer peptides. This review introduces the role of peptides in the immunomodulation of innate and adaptive immune cells, followed by a link between peptides in the innate and adaptive immune systems. The peptides are discussed in detail, following a classification according to their effects on different innate and adaptive immune cells, as well as immune checkpoints. Subsequently, two delivery strategies for peptides as drugs are presented: peptide self-assemblies and peptide-functionalized nanocarriers. The concluding remarks regarding the challenges and potential solutions of peptides for tumor immunotherapy are presented.
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Affiliation(s)
- Yang Song
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang, 421001, China
| | - Longtianyang Lei
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang, 421001, China
| | - Xingyu Cai
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang, 421001, China
| | - Hua Wei
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang, 421001, China
| | - Cui-Yun Yu
- Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, School of Pharmaceutical Science, Hengyang Medical School, University of South China, Hengyang, 421001, China
- Affiliated Hospital of Hunan Academy of Chinese Medicine, Hunan Academy of Chinese Medicine, Changsha, 410013, China
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3
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Adak A, Castelletto V, de Sousa A, Karatzas KA, Wilkinson C, Khunti N, Seitsonen J, Hamley IW. Self-Assembly and Antimicrobial Activity of Lipopeptides Containing Lysine-Rich Tripeptides. Biomacromolecules 2024; 25:1205-1213. [PMID: 38204421 PMCID: PMC10865344 DOI: 10.1021/acs.biomac.3c01184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/21/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024]
Abstract
The conformation and self-assembly of two pairs of model lipidated tripeptides in aqueous solution are probed using a combination of spectroscopic methods along with cryogenic-transmission electron microscopy (cryo-TEM) and small-angle X-ray scattering (SAXS). The palmitoylated lipopeptides comprise C16-YKK or C16-WKK (with two l-lysine residues) or their respective derivatives containing d-lysine (k), i.e., C16-Ykk and C16-Wkk. All four molecules self-assemble into spherical micelles which show structure factor effects in SAXS profiles due to intermicellar packing in aqueous solution. Consistent with micellar structures, the tripeptides in the coronas have a largely unordered conformation, as probed using spectroscopic methods. The molecules are found to have good cytocompatibility with fibroblasts at sufficiently low concentrations, although some loss of cell viability is noted at the highest concentrations examined (above the critical aggregation concentration of the lipopeptides, determined from fluorescence dye probe measurements). Preliminary tests also showed antimicrobial activity against both Gram-negative and Gram-positive bacteria.
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Affiliation(s)
- Anindyasundar Adak
- School
of Chemistry, Pharmacy and Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AH, U.K.
| | - Valeria Castelletto
- School
of Chemistry, Pharmacy and Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AH, U.K.
| | - Ana de Sousa
- School
of Chemistry, Pharmacy and Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AH, U.K.
| | - Kimon-Andreas Karatzas
- School
of Chemistry, Pharmacy and Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AH, U.K.
| | - Callum Wilkinson
- School
of Chemistry, Pharmacy and Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AH, U.K.
| | - Nikul Khunti
- Diamond
Light Source, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0DE, U.K.
| | - Jani Seitsonen
- Nanomicroscopy
Center, Aalto University, Puumiehenkuja 2, FIN-02150 Espoo, Finland
| | - Ian W. Hamley
- School
of Chemistry, Pharmacy and Food Biosciences, University of Reading, Whiteknights, Reading RG6 6AH, U.K.
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4
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Guo J, Rich-New ST, Liu C, Huang Y, Tan W, He H, Yi M, Zhang X, Egelman EH, Wang F, Xu B. Hierarchical Assembly of Intrinsically Disordered Short Peptides. Chem 2023; 9:2530-2546. [PMID: 38094164 PMCID: PMC10715794 DOI: 10.1016/j.chempr.2023.04.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2023]
Abstract
The understanding on how short peptide assemblies transit from disorder to order remains limited due to the lack of atomistic structures. Here we report cryo-EM structure of the nanofibers short intrinsically disordered peptides (IDPs). Upon lowering pH or adding calcium ions, the IDP transitions from individual nanoparticles to nanofibers containing an aromatic core and a disordered periphery comprised of 2 to 5 amino acids. Protonating the phosphate or adding more metal ions further assembles the nanofibers into filament bundles. The assemblies of the IDP analogs with controlled chemistry, such as phosphorylation site, hydrophobic interactions, and sequences indicate that metal ions interact with the flexible periphery of the nanoparticles of the IDPs to form fibrils and enhance the interfibrillar interactions to form filament bundles. Illustrating that an IDP self-assembles from disorder to order, this work offers atomistic molecular insights to understand assemblies of short peptides driven by noncovalent interactions.
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Affiliation(s)
- Jiaqi Guo
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Shane T. Rich-New
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Chen Liu
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Yimeng Huang
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Weiyi Tan
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Hongjian He
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Meihui Yi
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, USA
| | - Xixiang Zhang
- Physical Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia
| | - Edward H. Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908, USA
| | - Fengbin Wang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35233, USA
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908, USA
- O’Neal Comprehensive Cancer Center University of Alabama at Birmingham, Birmingham, AL 35233, USA
| | - Bing Xu
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, MA 02453, USA
- Lead contact
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5
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Hamley IW, Castelletto V. Small-angle scattering techniques for peptide and peptide hybrid nanostructures and peptide-based biomaterials. Adv Colloid Interface Sci 2023; 318:102959. [PMID: 37473606 DOI: 10.1016/j.cis.2023.102959] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/03/2023] [Accepted: 07/04/2023] [Indexed: 07/22/2023]
Abstract
The use of small-angle scattering (SAS) in the study of the self-assembly of peptides and peptide conjugates (lipopeptides, polymer-peptide conjugates and others) is reviewed, highlighting selected research that illustrates different methods and analysis techniques. Both small-angle x-ray scattering (SAXS) and small-angle neutron scattering (SANS) are considered along with examples that exploit their unique capabilities. For SAXS, this includes the ability to perform rapid measurements enabling high throughput or fast kinetic studies and measurements under dilute conditions. For SANS, contrast variation using H2O/D2O mixtures enables the study of peptides interacting with lipids and TR-SANS (time-resolved SANS) studies of exchange kinetics and/or peptide-induced structural changes. Examples are provided of studies measuring form factors of different self-assembled structures (micelles, fibrils, nanotapes, nanotubes etc) as well as structure factors from ordered phases (lyotropic mesophases), peptide gels and hybrid materials such as membranes formed by mixing peptides with polysaccharides or peptide/liposome mixtures. SAXS/WAXS (WAXS: wide-angle x-ray scattering) on peptides and peptide hybrids is also discussed, and the review concludes with a perspective on potential future directions for research in the field.
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Affiliation(s)
- Ian W Hamley
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, UK.
| | - Valeria Castelletto
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, UK
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6
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Ehm T, Shinar H, Jacoby G, Meir S, Koren G, Segal Asher M, Korpanty J, Thompson MP, Gianneschi NC, Kozlov MM, Azoulay-Ginsburg S, Amir RJ, Rädler JO, Beck R. Self-Assembly of Tunable Intrinsically Disordered Peptide Amphiphiles. Biomacromolecules 2023; 24:98-108. [PMID: 36469950 PMCID: PMC9832477 DOI: 10.1021/acs.biomac.2c00866] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Intrinsically disordered peptide amphiphiles (IDPAs) present a novel class of synthetic conjugates that consist of short hydrophilic polypeptides anchored to hydrocarbon chains. These hybrid polymer-lipid block constructs spontaneously self-assemble into dispersed nanoscopic aggregates or ordered mesophases in aqueous solution due to hydrophobic interactions. Yet, the possible sequence variations and their influence on the self-assembly structures are vast and have hardly been explored. Here, we measure the nanoscopic self-assembled structures of four IDPA systems that differ by their amino acid sequence. We show that permutations in the charge pattern along the sequence remarkably alter the headgroup conformation and consequently alter the pH-triggered phase transitions between spherical, cylindrical micelles and hexagonal condensed phases. We demonstrate that even a single amino acid mutation is sufficient to tune structural transitions in the condensed IDPA mesophases, while peptide conformations remain unfolded and disordered. Furthermore, alteration of the peptide sequence can render IDPAs to become susceptible to enzymatic cleavage and induce enzymatically activated phase transitions. These results hold great potential for embedding multiple functionalities into lipid nanoparticle delivery systems by incorporating IDPAs with the desired properties.
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Affiliation(s)
- Tamara Ehm
- Raymond
& Beverly Sackler School of Physics & Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel,Faculty
of Physics and Center for NanoScience, Ludwig-Maximilians-Universität, MünchenD-80539, Germany,The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Hila Shinar
- Raymond
& Beverly Sackler School of Physics & Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Guy Jacoby
- Raymond
& Beverly Sackler School of Physics & Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Sagi Meir
- Raymond
& Beverly Sackler School of Physics & Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Gil Koren
- Raymond
& Beverly Sackler School of Physics & Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Merav Segal Asher
- The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel,Raymond
& Beverly Sackler School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Joanna Korpanty
- Department
of Chemistry, International Institute for Nanotechnology, Chemistry
of Life Processes Institute, Simpson Querrey Institute, Northwestern University, Evanston, Illinois 60208, United States
| | - Matthew P. Thompson
- Department
of Chemistry, International Institute for Nanotechnology, Chemistry
of Life Processes Institute, Simpson Querrey Institute, Northwestern University, Evanston, Illinois 60208, United States
| | - Nathan C. Gianneschi
- Department
of Chemistry, International Institute for Nanotechnology, Chemistry
of Life Processes Institute, Simpson Querrey Institute, Northwestern University, Evanston, Illinois 60208, United States,Department
of Materials Science & Engineering, Department of Biomedical Engineering
and Department of Pharmacology, Northwestern
University, Evanston, Illinois 60208, United States
| | - Michael M. Kozlov
- The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,Raymond
& Beverly Sackler School of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Salome Azoulay-Ginsburg
- Raymond
& Beverly Sackler School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Roey J. Amir
- The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel,Raymond
& Beverly Sackler School of Chemistry, Tel Aviv University, Tel Aviv 6997801, Israel,The
ADAMA Center for Novel Delivery Systems in Crop Protection, Tel Aviv University, Tel Aviv 6997801, Israel,Email
| | - Joachim O. Rädler
- Faculty
of Physics and Center for NanoScience, Ludwig-Maximilians-Universität, MünchenD-80539, Germany,
| | - Roy Beck
- Raymond
& Beverly Sackler School of Physics & Astronomy, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for Physics & Chemistry of Living Systems, Tel Aviv University, Tel Aviv 6997801, Israel,The
Center for NanoTechnology & NanoScience, Tel Aviv University, Tel Aviv 6997801, Israel,
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7
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Rizzuti B. Nanomedicines Meet Disordered Proteins: A Shift from Traditional Materials and Concepts to Innovative Polymers. J Pers Med 2022; 12:jpm12101662. [PMID: 36294800 PMCID: PMC9604919 DOI: 10.3390/jpm12101662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 09/30/2022] [Indexed: 11/16/2022] Open
Abstract
Water-soluble nanomedicines have been widely studied for the targeted delivery of drugs for a very long time. As a notable example, biomaterials based on N-(2-hydroxypropyl) methacrylamide (HPMA) copolymers have been under investigation for nearly half a century. In particular, anticancer drug carriers have been developed under the assumption that the leading mechanism with a therapeutic impact on solid tumors is the enhanced permeability and retention (EPR) effect, which dates back more than three decades. Nevertheless, these (and other) materials and concepts have encountered several barriers in their successful translation into clinical practice, and future nanomedicines need improvements in both passive and active targeting to their site of action. Notions borrowed from recent studies on intrinsically disordered proteins (IDPs) seem promising for enhancing the self-assembly, stimuli-responsiveness, and recognition properties of protein/peptide-based copolymers. Accordingly, IDP-based nanomedicines are ready to give new impetus to more traditional research in this field.
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Affiliation(s)
- Bruno Rizzuti
- CNR-NANOTEC, Sede Secondaria Rende (CS), Department of Physics, University of Calabria, 87036 Rende, Italy
- Institute of Biocomputation and Physics of Complex Systems-Joint Unit GBsC-CSIC-BIFI, University of Zaragoza, 50018 Zaragoza, Spain
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8
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In-Silico Analysis of pH-Dependent Liquid-Liquid Phase Separation in Intrinsically Disordered Proteins. Biomolecules 2022; 12:biom12070974. [PMID: 35883530 PMCID: PMC9313257 DOI: 10.3390/biom12070974] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/06/2022] [Accepted: 07/08/2022] [Indexed: 02/04/2023] Open
Abstract
Intrinsically disordered proteins (IDPs) are essential players in the assembly of biomolecular condensates during liquid–liquid phase separation (LLPS). Disordered regions (IDRs) are significantly exposed to the solvent and, therefore, highly influenced by fluctuations in the microenvironment. Extrinsic factors, such as pH, modify the solubility and disorder state of IDPs, which in turn may impact the formation of liquid condensates. However, little attention has been paid to how the solution pH influences LLPS, despite knowing that this process is context-dependent. Here, we have conducted a large-scale in-silico analysis of pH-dependent solubility and disorder in IDRs known to be involved in LLPS (LLPS-DRs). We found that LLPS-DRs present maximum solubility around physiological pH, where LLPS often occurs, and identified significant differences in solubility and disorder between proteins that can phase-separate by themselves or those that require a partner. We also analyzed the effect of mutations in the resulting solubility profiles of LLPS-DRs and discussed how, as a general trend, LLPS-DRs display physicochemical properties that permit their LLPS at physiologically relevant pHs.
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9
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Ehm T, Philipp J, Barkey M, Ober M, Brinkop AT, Simml D, von Westphalen M, Nickel B, Beck R, Rädler JO. 3D-printed SAXS chamber for controlled in situ dialysis and optical characterization. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:1014-1019. [PMID: 35787568 PMCID: PMC9255564 DOI: 10.1107/s1600577522005136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 05/12/2022] [Indexed: 06/15/2023]
Abstract
3D printing changes the scope of how samples can be mounted for small-angle X-ray scattering (SAXS). In this paper a 3D-printed X-ray chamber, which allows for in situ exchange of buffer and in situ optical transmission spectroscopy, is presented. The chamber is made of cyclic olefin copolymers (COC), including COC X-ray windows providing ultra-low SAXS background. The design integrates a membrane insert for in situ dialysis of the 100 µl sample volume against a reservoir, which enables measurements of the same sample under multiple conditions using an in-house X-ray setup equipped with a 17.4 keV molybdenum source. The design's capabilities are demonstrated by measuring reversible structural changes in lipid and polymer systems as a function of salt concentration and pH. In the same chambers optical light transmission spectroscopy was carried out measuring the optical turbidity of the mesophases and local pH values using pH-responsive dyes. Microfluidic exchange and optical spectroscopy combined with in situ X-ray scattering enables vast applications for the study of responsive materials.
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Affiliation(s)
- Tamara Ehm
- School of Physics and Astronomy, Center for Physics and Chemistry of Living Systems, and Center for Nanoscience and Nanotechnology, Tel Aviv University, Ramat Aviv, Israel
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Julian Philipp
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Martin Barkey
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Martina Ober
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Achim Theo Brinkop
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - David Simml
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Miriam von Westphalen
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Bert Nickel
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
| | - Roy Beck
- School of Physics and Astronomy, Center for Physics and Chemistry of Living Systems, and Center for Nanoscience and Nanotechnology, Tel Aviv University, Ramat Aviv, Israel
| | - Joachim O. Rädler
- Faculty of Physics, Ludwig-Maximilians-Universität, Geschwister-Scholl-Platz 1, Munich, Germany
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