1
|
Faraji P, Borchert A, Ahmadian S, Kuhn H. Butylated Hydroxytoluene (BHT) Protects SH-SY5Y Neuroblastoma Cells from Ferroptotic Cell Death: Insights from In Vitro and In Vivo Studies. Antioxidants (Basel) 2024; 13:242. [PMID: 38397840 PMCID: PMC10886092 DOI: 10.3390/antiox13020242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/06/2024] [Accepted: 02/13/2024] [Indexed: 02/25/2024] Open
Abstract
Ferroptosis is a special kind of programmed cell death that has been implicated in the pathogenesis of a large number of human diseases. It involves dysregulated intracellular iron metabolism and uncontrolled lipid peroxidation, which together initiate intracellular ferroptotic signalling pathways leading to cellular suicide. Pharmacological interference with ferroptotic signal transduction may prevent cell death, and thus patients suffering from ferroptosis-related diseases may benefit from such treatment. Butylated hydroxytoluene (BHT) is an effective anti-oxidant that is frequently used in oil chemistry and in cosmetics to prevent free-radical-mediated lipid peroxidation. Since it functions as a radical scavenger, it has previously been reported to interfere with ferroptotic signalling. Here, we show that BHT prevents RSL3- and ML162-induced ferroptotic cell death in cultured human neuroblastoma cells (SH-SY5Y) in a dose-dependent manner. It prevents the RSL3-induced oxidation of membrane lipids and normalises the RSL3-induced inhibition of the intracellular catalytic activity of glutathione peroxidase 4. The systemic application of BHT in a rat Alzheimer's disease model prevented the upregulation of the expression of ferroptosis-related genes. Taken together, these data indicate that BHT interferes with ferroptotic signalling in cultured neuroblastoma cells and may prevent ferroptotic cell death in an animal Alzheimer's disease model.
Collapse
Affiliation(s)
- Parisa Faraji
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany; (P.F.); (A.B.)
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran 1417614335, Iran
| | - Astrid Borchert
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany; (P.F.); (A.B.)
| | - Shahin Ahmadian
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran 1417614335, Iran
| | - Hartmut Kuhn
- Department of Biochemistry, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt Universität zu Berlin, Charitéplatz 1, 10117 Berlin, Germany; (P.F.); (A.B.)
| |
Collapse
|
2
|
Osiewacz HD. The impact of biomembranes and their dynamics on organismic aging: insights from a fungal aging model. Front Aging 2024; 5:1356697. [PMID: 38327611 PMCID: PMC10847301 DOI: 10.3389/fragi.2024.1356697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2023] [Accepted: 01/09/2024] [Indexed: 02/09/2024]
Abstract
Biomembranes fulfill several essential functions. They delimitate cells and control the exchange of compounds between cells and the environment. They generate specialized cellular reaction spaces, house functional units such as the respiratory chain (RC), and are involved in content trafficking. Biomembranes are dynamic and able to adjust their properties to changing conditions and requirements. An example is the inner mitochondrial membrane (IMM), which houses the RC involved in the formation of adenosine triphosphate (ATP) and the superoxide anion as a reactive oxygen species (ROS). The IMM forms a characteristic ultrastructure that can adapt to changing physiological situations. In the fungal aging model Podospora anserina, characteristic age-related changes of the mitochondrial ultrastructure occur. More recently, the impact of membranes on aging was extended to membranes involved in autophagy, an important pathway involved in cellular quality control (QC). Moreover, the effect of oleic acid on the lifespan was linked to basic biochemical processes and the function of membranes, providing perspectives for the elucidation of the mechanistic effects of this nutritional component, which positively affects human health and aging.
Collapse
Affiliation(s)
- Heinz D. Osiewacz
- Institute for Molecular Biosciences, Faculty of Biosciences, Goethe University, Frankfurt, Germany
| |
Collapse
|
3
|
Wawrzkiewicz-Jałowiecka A, Fuliński A. Brownian Aging as One of the Mechanistic Components That Shape the Single-Channel Ionic Currents through Biological and Synthetic Membranes. Membranes (Basel) 2023; 13:879. [PMID: 37999365 PMCID: PMC10673163 DOI: 10.3390/membranes13110879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 10/26/2023] [Accepted: 11/08/2023] [Indexed: 11/25/2023]
Abstract
Semipermeable membranes enable the separation of a given system from its environment. In biological terms, they are responsible for cells' identity. In turn, the functioning of ion channels is crucial for the control of ionic fluxes across the membranes and, consequently, for the exchange of chemical and electrical signals. This paper presents a model and simulations of currents through ionic nanochannels in an attempt to better understand the physical mechanism(s) of open/closed (O/C) sequences, i.e., random interruptions of ionic flows through channels observed in all known biochannels and in some synthetic nanopores. We investigate whether aging, i.e., the changes in Brownian motion characteristics with the lapse of time, may be at least one of the sources of the O/C sequences (in addition to the gating machinery in biochannels). The simulations based on the approximated nanostructure of ion channels confirm this postulation. The results also show the possibility of changing the O/C characteristics through an appropriate alteration of the channel surroundings. This observation may be valuable in technical uses of nanochannels in synthetic membranes and allow for a better understanding of the reason for the differences between the biochannels' activity in diverse biological membranes. Proposals of experimental verification of this aging O/C hypothesis are also presented.
Collapse
Affiliation(s)
- Agata Wawrzkiewicz-Jałowiecka
- Department of Physical Chemistry and Technology of Polymers, Silesian University of Technology, Strzody 9, 44-100 Gliwice, Poland
| | - Andrzej Fuliński
- Institute of Theoretical Physics, Jagiellonian University, Łojasiewicza 11, 30-348 Kraków, Poland
| |
Collapse
|
4
|
Semenov AY, Tikhonov AN. Electrometric and Electron Paramagnetic Resonance Measurements of a Difference in the Transmembrane Electrochemical Potential: Photosynthetic Subcellular Structures and Isolated Pigment-Protein Complexes. Membranes (Basel) 2023; 13:866. [PMID: 37999352 PMCID: PMC10673362 DOI: 10.3390/membranes13110866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 10/23/2023] [Accepted: 10/26/2023] [Indexed: 11/25/2023]
Abstract
A transmembrane difference in the electrochemical potentials of protons (ΔμH+) serves as a free energy intermediate in energy-transducing organelles of the living cell. The contributions of two components of the ΔμH+ (electrical, Δψ, and concentrational, ΔpH) to the overall ΔμH+ value depend on the nature and lipid composition of the energy-coupling membrane. In this review, we briefly consider several of the most common instrumental (electrometric and EPR) methods for numerical estimations of Δψ and ΔpH. In particular, the kinetics of the flash-induced electrometrical measurements of Δψ in bacterial chromatophores, isolated bacterial reaction centers, and Photosystems I and II of the oxygenic photosynthesis, as well as the use of pH-sensitive molecular indicators and kinetic data regarding pH-dependent electron transport in chloroplasts, have been reviewed. Further perspectives on the application of these methods to solve some fundamental and practical problems of membrane bioenergetics are discussed.
Collapse
Affiliation(s)
- Alexey Yu. Semenov
- A.N. Belozersky Institute of Physical-Chemical Biology, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia;
| | | |
Collapse
|
5
|
Cordeiro MM, Filipe HAL, dos Santos P, Samelo J, Ramalho JPP, Loura LMS, Moreno MJ. Interaction of Hoechst 33342 with POPC Membranes at Different pH Values. Molecules 2023; 28:5640. [PMID: 37570608 PMCID: PMC10420284 DOI: 10.3390/molecules28155640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/18/2023] [Accepted: 07/21/2023] [Indexed: 08/13/2023] Open
Abstract
Hoechst 33342 (H33342) is a fluorescent probe that is commonly used to stain the DNA of living cells. To do so, it needs to interact with and permeate through cell membranes, despite its high overall charge at physiological pH values. In this work, we address the effect of pH in the association of H33342 with lipid bilayers using a combined experimental and computational approach. The partition of H33342 to 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid membranes was experimentally quantified using fluorescence spectroscopy and isothermal titration calorimetry (ITC) measurements. Quantum chemical calculations were performed to select the most stable isomer of H33342 for the overall charges 0, +1, and +2, expected to predominate across the 5 < pH < 10 range. The interaction of these isomers with POPC bilayers was then studied by both unrestrained and umbrella sampling molecular dynamics (MD) simulations. Both experimental results and computational free energy profiles indicate that the partition coefficient of H33342 displays a small variation over a wide pH range, not exceeding one order of magnitude. The enthalpy variation upon partition to the membrane suggests efficient hydrogen bonding between the probe and the lipid, namely, for the protonated +2 form, which was confirmed in the MD simulation studies. The relatively high lipophilicity obtained for the charged species contrasts with the decrease in their general hydrophobicity as estimated from octanol/water partition. This highlights the distinction between lipophilicity and hydrophobicity, as well as the importance of considering the association with lipid bilayers when predicting the affinity for biomembranes.
Collapse
Affiliation(s)
- Margarida M. Cordeiro
- Coimbra Chemistry Center, Institute of Molecular Sciences (CQC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal; (M.M.C.); (H.A.L.F.); (J.S.)
- Department of Chemistry, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal
| | - Hugo A. L. Filipe
- Coimbra Chemistry Center, Institute of Molecular Sciences (CQC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal; (M.M.C.); (H.A.L.F.); (J.S.)
- Polytechnic of Guarda, CPIRN-IPG—Center of Potential and Innovation of Natural Resources, 6300-559 Guarda, Portugal
| | - Patrícia dos Santos
- Coimbra Chemistry Center, Institute of Molecular Sciences (CQC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal; (M.M.C.); (H.A.L.F.); (J.S.)
- Department of Chemistry, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal
| | - Jaime Samelo
- Coimbra Chemistry Center, Institute of Molecular Sciences (CQC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal; (M.M.C.); (H.A.L.F.); (J.S.)
- Department of Chemistry, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal
| | - João P. Prates Ramalho
- LAQV, REQUIMTE, Hercules Laboratory, Department of Chemistry, School of Science and Technology, University of Évora, 7000-671 Évora, Portugal;
| | - Luís M. S. Loura
- Coimbra Chemistry Center, Institute of Molecular Sciences (CQC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal; (M.M.C.); (H.A.L.F.); (J.S.)
- CNC—Center for Neuroscience and Cell Biology, University of Coimbra, 3004-535 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Maria J. Moreno
- Coimbra Chemistry Center, Institute of Molecular Sciences (CQC-IMS), University of Coimbra, 3004-535 Coimbra, Portugal; (M.M.C.); (H.A.L.F.); (J.S.)
- Department of Chemistry, Faculty of Sciences and Technology, University of Coimbra, 3004-535 Coimbra, Portugal
- CNC—Center for Neuroscience and Cell Biology, University of Coimbra, 3004-535 Coimbra, Portugal
| |
Collapse
|
6
|
Mavroidi B, Kaminari A, Sakellis E, Sideratou Z, Tsiourvas D. Carbon Dots-Biomembrane Interactions and Their Implications for Cellular Drug Delivery. Pharmaceuticals (Basel) 2023; 16:833. [PMID: 37375780 DOI: 10.3390/ph16060833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
The effect of carbon dots (CDs) on a model blayer membrane was studied as a means of comprehending their ability to affect cell membranes. Initially, the interaction of N-doped carbon dots with a biophysical liposomal cell membrane model was investigated by dynamic light scattering, z-potential, temperature-modulated differential scanning calorimetry, and membrane permeability. CDs with a slightly positive charge interacted with the surface of the negative-charged liposomes and evidence indicated that the association of CDs with the membrane affects the structural and thermodynamic properties of the bilayer; most importantly, it enhances the bilayer's permeability against doxorubicin, a well-known anticancer drug. The results, like those of similar studies that surveyed the interaction of proteins with lipid membranes, suggest that carbon dots are partially embedded in the bilayer. In vitro experiments employing breast cancer cell lines and human healthy dermal cells corroborated the findings, as it was shown that the presence of CDs in the culture medium selectively enhanced cell internalization of doxorubicin and, subsequently, increased its cytotoxicity, acting as a drug sensitizer.
Collapse
Affiliation(s)
- Barbara Mavroidi
- Institute of Biosciences and Applications, National Centre for Scientific Research "Demokritos", 15310 Aghia Paraskevi, Greece
| | - Archontia Kaminari
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research "Demokritos", 15310 Aghia Paraskevi, Greece
| | - Elias Sakellis
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research "Demokritos", 15310 Aghia Paraskevi, Greece
| | - Zili Sideratou
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research "Demokritos", 15310 Aghia Paraskevi, Greece
| | - Dimitris Tsiourvas
- Institute of Nanoscience and Nanotechnology, National Centre for Scientific Research "Demokritos", 15310 Aghia Paraskevi, Greece
| |
Collapse
|
7
|
Ferrauto G, Terreno E. Compartmentalized agents: A powerful strategy for enhancing the detection sensitivity of chemical exchange saturation transfer contrast. NMR Biomed 2023; 36:e4791. [PMID: 35731545 DOI: 10.1002/nbm.4791] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 06/17/2022] [Accepted: 06/19/2022] [Indexed: 05/23/2023]
Abstract
Since the very beginnings of the chemical exchange saturation transfer (CEST) technique, poor overall sensitivity has appeared to be one of its strongest limitations for future applications. Research has therefore focused on designing systems, such as supramolecular and nanosized agents, that contain a high number of magnetically equivalent mobile spins. However, the number of mobile spins offered by these systems is still limited by their composition and surface/volume ratio. The design of compartmentalized agents, that is, systems where an aqueous inner core is separated from the MRI-detected bulk pool via a semipermeable barrier/membrane, is very much a step forward for the technique. These vesicular systems can (i) act as biocompatible and versatile carriers for dia-, para-, and hetero-nuclear CEST probes, thus offering new application options; and (ii) act as CEST probes themselves via the encapsulation of a suitable agent (e.g., a paramagnetic shift reagent) that can change the resonance frequency of the spin pool in the inner compartment only. LipoCEST agents were the pioneers in the latter category, as they are able to grant picomolar sensitivity (in terms of nanoparticle concentration), and paved the way for new applications for CEST agents, especially in the theranostic research area. The use of larger, natural vesicular systems, such as yeasts and cells, in which the huge number of intravesicular spins lowers the detection threshold to a femtomolar limit, is a further step forward in the development of compartmentalized CEST agents. Finally, interesting combinations of nanovesicular and cellular compartmentalized systems have been proposed, thus highlighting how the approach has the potential to drive CEST agents towards completing their journey to mature clinical translation.
Collapse
Affiliation(s)
- Giuseppe Ferrauto
- Center for Molecular and Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| | - Enzo Terreno
- Center for Molecular and Preclinical Imaging, Department of Molecular Biotechnology and Health Sciences, University of Turin, Turin, Italy
| |
Collapse
|
8
|
Lipowsky R, Ghosh R, Satarifard V, Sreekumari A, Zamaletdinov M, Różycki B, Miettinen M, Grafmüller A. Leaflet Tensions Control the Spatio-Temporal Remodeling of Lipid Bilayers and Nanovesicles. Biomolecules 2023; 13:926. [PMID: 37371505 DOI: 10.3390/biom13060926] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 05/24/2023] [Accepted: 05/26/2023] [Indexed: 06/29/2023] Open
Abstract
Biological and biomimetic membranes are based on lipid bilayers, which consist of two monolayers or leaflets. To avoid bilayer edges, which form when the hydrophobic core of such a bilayer is exposed to the surrounding aqueous solution, a single bilayer closes up into a unilamellar vesicle, thereby separating an interior from an exterior aqueous compartment. Synthetic nanovesicles with a size below 100 nanometers, traditionally called small unilamellar vesicles, have emerged as potent platforms for the delivery of drugs and vaccines. Cellular nanovesicles of a similar size are released from almost every type of living cell. The nanovesicle morphology has been studied by electron microscopy methods but these methods are limited to a single snapshot of each vesicle. Here, we review recent results of molecular dynamics simulations, by which one can monitor and elucidate the spatio-temporal remodeling of individual bilayers and nanovesicles. We emphasize the new concept of leaflet tensions, which control the bilayers' stability and instability, the transition rates of lipid flip-flops between the two leaflets, the shape transformations of nanovesicles, the engulfment and endocytosis of condensate droplets and rigid nanoparticles, as well as nanovesicle adhesion and fusion. To actually compute the leaflet tensions, one has to determine the bilayer's midsurface, which represents the average position of the interface between the two leaflets. Two particularly useful methods to determine this midsurface are based on the density profile of the hydrophobic lipid chains and on the molecular volumes.
Collapse
Affiliation(s)
- Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Rikhia Ghosh
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- Icahn School of Medicine Mount Sinai, New York, NY 10029, USA
| | - Vahid Satarifard
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- Yale Institute for Network Science, Yale University, New Haven, CT 06520, USA
| | - Aparna Sreekumari
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- Department of Physics, Indian Institute of Technology Palakkad, Palakkad 678 623, India
| | - Miftakh Zamaletdinov
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| | - Bartosz Różycki
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, 02-668 Warsaw, Poland
| | - Markus Miettinen
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
- Department of Chemistry, University of Bergen, 5020 Bergen, Norway
| | - Andrea Grafmüller
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| |
Collapse
|
9
|
Foley SL, Varma M, Hossein A, Deserno M. Elastic and thermodynamic consequences of lipid membrane asymmetry. Emerg Top Life Sci 2023:ETLS20220084. [PMID: 36880567 DOI: 10.1042/ETLS20220084] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 02/02/2023] [Accepted: 02/10/2023] [Indexed: 03/08/2023]
Abstract
Many cellular lipid bilayers consist of leaflets that differ in their lipid composition - a non-equilibrium state actively maintained by cellular sorting processes that counter passive lipid flip-flop. While this lipidomic aspect of membrane asymmetry has been known for half a century, its elastic and thermodynamic ramifications have garnered attention only fairly recently. Notably, the torque arising when lipids of different spontaneous curvature reside in the two leaflets can be counterbalanced by a difference in lateral mechanical stress between them. Such membranes can be essentially flat in their relaxed state, despite being compositionally strongly asymmetric, but they harbor a surprisingly large but macroscopically invisible differential stress. This hidden stress can affect a wide range of other membrane properties, such as the resistance to bending, the nature of phase transitions in its leaflets, and the distribution of flippable species, most notably sterols. In this short note we offer a concise overview of our recently proposed basic framework for capturing the interplay between curvature, lateral stress, leaflet phase behavior, and cholesterol distribution in generally asymmetric membranes, and how its implied signatures might be used to learn more about the hidden but physically consequential differential stress.
Collapse
|
10
|
Lipowsky R. Remodeling of Biomembranes and Vesicles by Adhesion of Condensate Droplets. Membranes (Basel) 2023; 13:223. [PMID: 36837726 PMCID: PMC9965763 DOI: 10.3390/membranes13020223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Condensate droplets are formed in aqueous solutions of macromolecules that undergo phase separation into two liquid phases. A well-studied example are solutions of the two polymers PEG and dextran which have been used for a long time in biochemical analysis and biotechnology. More recently, phase separation has also been observed in living cells where it leads to membrane-less or droplet-like organelles. In the latter case, the condensate droplets are enriched in certain types of proteins. Generic features of condensate droplets can be studied in simple binary mixtures, using molecular dynamics simulations. In this review, I address the interactions of condensate droplets with biomimetic and biological membranes. When a condensate droplet adheres to such a membrane, the membrane forms a contact line with the droplet and acquires a very high curvature close to this line. The contact angles along the contact line can be observed via light microscopy, lead to a classification of the possible adhesion morphologies, and determine the affinity contrast between the two coexisting liquid phases and the membrane. The remodeling processes generated by condensate droplets include wetting transitions, formation of membrane nanotubes as well as complete engulfment and endocytosis of the droplets by the membranes.
Collapse
Affiliation(s)
- Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14424 Potsdam, Germany
| |
Collapse
|
11
|
Nieto-Garai JA, Contreras FX, Arboleya A, Lorizate M. Role of Protein-Lipid Interactions in Viral Entry. Adv Biol (Weinh) 2022; 6:e2101264. [PMID: 35119227 DOI: 10.1002/adbi.202101264] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/19/2021] [Indexed: 12/25/2022]
Abstract
The viral entry consists of several sequential events that ensure the attachment of the virus to the host cell and the introduction of its genetic material for the continuation of the replication cycle. Both cellular and viral lipids have gained a wider focus in recent years in the field of viral entry, as they are found to play key roles in different steps of the process. The specific role is summarized that lipids and lipid membrane nanostructures play in viral attachment, fusion, and immune evasion and how they can be targeted with antiviral therapies. Finally, some of the limitations of techniques commonly used for protein-lipid interactions studies are discussed, and new emerging tools are reviewed that can be applied to this field.
Collapse
Affiliation(s)
- Jon Ander Nieto-Garai
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Leioa, E-48940, Spain
| | - Francesc-Xabier Contreras
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Leioa, E-48940, Spain.,Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain.,Ikerbasque, Basque Foundation for Science, Bilbao, 48013, Spain
| | - Aroa Arboleya
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Leioa, E-48940, Spain.,Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain.,Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), Barrio Sarriena s/n, Leioa, E-48940, Spain
| | - Maier Lorizate
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country, Leioa, E-48940, Spain.,Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, Leioa, E-48940, Spain
| |
Collapse
|
12
|
Scollo F, Evci H, Amaro M, Jurkiewicz P, Sykora J, Hof M. What Does Time-Dependent Fluorescence Shift (TDFS) in Biomembranes (and Proteins) Report on? Front Chem 2021; 9:738350. [PMID: 34778202 PMCID: PMC8586494 DOI: 10.3389/fchem.2021.738350] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 09/21/2021] [Indexed: 11/17/2022] Open
Abstract
The organization of biomolecules and bioassemblies is highly governed by the nature and extent of their interactions with water. These interactions are of high intricacy and a broad range of methods based on various principles have been introduced to characterize them. As these methods view the hydration phenomena differently (e.g., in terms of time and length scales), a detailed insight in each particular technique is to promote the overall understanding of the stunning “hydration world.” In this prospective mini-review we therefore critically examine time-dependent fluorescence shift (TDFS)—an experimental method with a high potential for studying the hydration in the biological systems. We demonstrate that TDFS is very useful especially for phospholipid bilayers for mapping the interfacial region formed by the hydrated lipid headgroups. TDFS, when properly applied, reports on the degree of hydration and mobility of the hydrated phospholipid segments in the close vicinity of the fluorophore embedded in the bilayer. Here, the interpretation of the recorded TDFS parameters are thoroughly discussed, also in the context of the findings obtained by other experimental techniques addressing the hydration phenomena (e.g., molecular dynamics simulations, NMR spectroscopy, scattering techniques, etc.). The differences in the interpretations of TDFS outputs between phospholipid biomembranes and proteins are also addressed. Additionally, prerequisites for the successful TDFS application are presented (i.e., the proper choice of fluorescence dye for TDFS studies, and TDFS instrumentation). Finally, the effects of ions and oxidized phospholipids on the bilayer organization and headgroup packing viewed from TDFS perspective are presented as application examples.
Collapse
Affiliation(s)
- Federica Scollo
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Hüseyin Evci
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Mariana Amaro
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Piotr Jurkiewicz
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Jan Sykora
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the CAS, Prague, Czechia
| |
Collapse
|
13
|
Herrera-León C, Ramos-Martín F, Antonietti V, Sonnet P, D'Amelio N. The impact of phosphatidylserine exposure on cancer cell membranes on the activity of the anticancer peptide HB43. FEBS J 2021; 289:1984-2003. [PMID: 34767285 DOI: 10.1111/febs.16276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 10/19/2021] [Accepted: 11/10/2021] [Indexed: 02/04/2023]
Abstract
HB43 (FAKLLAKLAKKLL) is a synthetic peptide active against cell lines derived from breast, colon, melanoma, lung, prostate, and cervical cancers. Despite its remarkable spectrum of activity, the mechanism of action at the molecular level has never been investigated, preventing further optimization of its selectivity. The alternation of charged and hydrophobic residues suggests amphipathicity, but the formation of alpha-helical structure seems discouraged by its short length and the large number of positively charged residues. Using different biophysical and in silico approaches we show that HB43 is completely unstructured in solution but assumes alpha-helical conformation in the presence of DPC micelles and liposomes exposing phosphatidylserine (PS) used as mimics of cancer cell membranes. Membrane permeabilization assays demonstrate that the interaction leads to the preferential destabilization of PS-containing vesicles with respect to PC-containing ones, here used as noncancerous cell mimics. ssNMR reveals that HB43 is able to fluidify the internal structure of cancer-cell mimicking liposomes while MD simulations show its internalization in such bilayers. This is achieved by the formation of specific interactions between the lysine side chains and the carboxylate group of phosphatidylserine and/or the phosphate oxygen atoms of targeted phospholipids, which could catalyze the formation of the alpha helix required for internalization. With the aim of better understanding the peptide biocompatibility and the additional antibacterial activity, the interaction with noncancerous cell mimicking liposomes exposing phosphatidylcholine (PC) and bacterial mimicking bilayers exposing phosphatidylglycerol (PG) is also described.
Collapse
Affiliation(s)
- Claudia Herrera-León
- Unité de Génie Enzymatique et Cellulaire, UMR 7025, CNRS, Université de Picardie Jules Verne, Amiens, France
| | - Francisco Ramos-Martín
- Unité de Génie Enzymatique et Cellulaire, UMR 7025, CNRS, Université de Picardie Jules Verne, Amiens, France
| | - Viviane Antonietti
- Agents Infectieux, Résistance et Chimiothérapie, UFR de Pharmacie, AGIR UR 4294, Université de Picardie Jules Verne, Amiens, France
| | - Pascal Sonnet
- Agents Infectieux, Résistance et Chimiothérapie, UFR de Pharmacie, AGIR UR 4294, Université de Picardie Jules Verne, Amiens, France
| | - Nicola D'Amelio
- Unité de Génie Enzymatique et Cellulaire, UMR 7025, CNRS, Université de Picardie Jules Verne, Amiens, France
| |
Collapse
|
14
|
Auddya D, Zhang X, Gulati R, Vasan R, Garikipati K, Rangamani P, Rudraraju S. Biomembranes undergo complex, non-axisymmetric deformations governed by Kirchhoff-Love kinematicsand revealed by a three-dimensional computational framework. Proc Math Phys Eng Sci 2021; 477:20210246. [PMID: 35153593 PMCID: PMC8580429 DOI: 10.1098/rspa.2021.0246] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 10/11/2021] [Indexed: 01/10/2023] Open
Abstract
Biomembranes play a central role in various phenomena like locomotion of cells, cell-cell interactions, packaging and transport of nutrients, transmission of nerve impulses, and in maintaining organelle morphology and functionality. During these processes, the membranes undergo significant morphological changes through deformation, scission, and fusion. Modelling the underlying mechanics of such morphological changes has traditionally relied on reduced order axisymmetric representations of membrane geometry and deformation. Axisymmetric representations, while robust and extensively deployed, suffer from their inability to model-symmetry breaking deformations and structural bifurcations. To address this limitation, a three-dimensional computational mechanics framework for high fidelity modelling of biomembrane deformation is presented. The proposed framework brings together Kirchhoff–Love thin-shell kinematics, Helfrich-energy-based mechanics, and state-of-the-art numerical techniques for modelling deformation of surface geometries. Lipid bilayers are represented as spline-based surface discretizations immersed in a three-dimensional space; this enables modelling of a wide spectrum of membrane geometries, boundary conditions, and deformations that are physically admissible in a three-dimensional space. The mathematical basis of the framework and its numerical machinery are presented, and their utility is demonstrated by modelling three classical, yet non-trivial, membrane deformation problems: formation of tubular shapes and their lateral constriction, Piezo1-induced membrane footprint generation and gating response, and the budding of membranes by protein coats during endocytosis. For each problem, the full three-dimensional membrane deformation is captured, potential symmetry-breaking deformation paths identified, and various case studies of boundary and load conditions are presented. Using the endocytic vesicle budding as a case study, we also present a ‘phase diagram’ for its symmetric and broken-symmetry states.
Collapse
Affiliation(s)
- Debabrata Auddya
- Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Xiaoxuan Zhang
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Rahul Gulati
- Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Ritvik Vasan
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Krishna Garikipati
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.,Department of Mathematics, University of Michigan, Ann Arbor, MI 48109, USA.,Michigan Institute for Computational Discovery and Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093, USA
| | - Shiva Rudraraju
- Department of Mechanical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| |
Collapse
|
15
|
Lucherelli MA, Qian X, Weston P, Eredia M, Zhu W, Samorì P, Gao H, Bianco A, von dem Bussche A. Boron Nitride Nanosheets Can Induce Water Channels Across Lipid Bilayers Leading to Lysosomal Permeabilization. Adv Mater 2021; 33:e2103137. [PMID: 34553436 DOI: 10.1002/adma.202103137] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2021] [Revised: 07/17/2021] [Indexed: 06/13/2023]
Abstract
While the interaction between 2D materials and cells is of key importance to the development of nanomedicines and safe applications of nanotechnology, still little is known about the biological interactions of many emerging 2D materials. Here, an investigation of how hexagonal boron nitride (hBN) interacts with the cell membrane is carried out by combining molecular dynamics (MD), liquid-phase exfoliation, and in vitro imaging methods. MD simulations reveal that a sharp hBN wedge can penetrate a lipid bilayer and form a cross-membrane water channel along its exposed polar edges, while a round hBN sheet does not exhibit this behavior. It is hypothesized that such water channels can facilitate cross-membrane transport, with important consequences including lysosomal membrane permeabilization, an emerging mechanism of cellular toxicity that involves the release of cathepsin B and generation of radical oxygen species leading to cell apoptosis. To test this hypothesis, two types of hBN nanosheets, one with a rhomboidal, cornered morphology and one with a round morphology, are prepared, and human lung epithelial cells are exposed to both materials. The cornered hBN with lateral polar edges results in a dose-dependent cytotoxic effect, whereas round hBN does not cause significant toxicity, thus confirming our premise.
Collapse
Affiliation(s)
- Matteo Andrea Lucherelli
- CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR 3572, University of Strasbourg, ISIS, Strasbourg, 67000, France
| | - Xuliang Qian
- School of Engineering, Brown University, Providence, RI 02912, USA
- School of Mechanical and Aerospace Engineering, College of Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore, 639798, Singapore
| | - Paula Weston
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI 02912, USA
| | - Matilde Eredia
- University of Strasbourg, CNRS, ISIS, Strasbourg, 67000, France
| | - Wenpeng Zhu
- School of Engineering, Brown University, Providence, RI 02912, USA
- School of Physics, Sun Yat-sen University, Guangzhou, 510275, China
| | - Paolo Samorì
- University of Strasbourg, CNRS, ISIS, Strasbourg, 67000, France
| | - Huajian Gao
- School of Engineering, Brown University, Providence, RI 02912, USA
- School of Mechanical and Aerospace Engineering, College of Engineering, Nanyang Technological University, 70 Nanyang Drive, Singapore, 639798, Singapore
- Institute of High Performance Computing, A*STAR, Singapore, 138632, Singapore
| | - Alberto Bianco
- CNRS, Immunology, Immunopathology and Therapeutic Chemistry, UPR 3572, University of Strasbourg, ISIS, Strasbourg, 67000, France
| | - Annette von dem Bussche
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI 02912, USA
| |
Collapse
|
16
|
Abstract
Plasmalogens are a subclass of cell membrane glycerophospholipids that typically include vinyl- ether bond at the sn-1 position and polyunsaturated fatty acid at the sn-2 position. They are highly abundant in the neuronal, immune, and cardiovascular cell membranes. Despite the abundance of plasmalogens in a plethora of cells, tissues, and organs, the role of plasmalogens remains unclear. Plasmalogens are required for the proper function of integral membrane proteins, lipid rafts, cell signaling, and differentiation. More importantly, plasmalogens play a crucial role in the cell as an endogenous antioxidant that protects the cell membrane components such as phospholipids, unsaturated fatty acids, and lipoproteins from oxidative stress. The incorporation of vinyl-ether linked with alkyl chains in phospholipids alter the physicochemical properties (e.g., the hydrophilicity of the headgroup), packing density, and conformational order of the phospholipids within the biomembranes. Thus, plasmalogens play a significant role in determining the physical and chemical properties of the biomembrane such as its fluidity, thickness, and lateral pressure of the biomembrane. Insights on the important structural and functional properties of plasmalogens may help us to understand the molecular mechanism of membrane transformation, vesicle formation, and vesicular fusion, especially at the synaptic vesicles where plasmalogens are rich and essential for neuronal function. Although many aspects of plasmalogen phospholipid involvement in membrane transformation identified through in vitro experiments and membrane mimic systems, remain to be confirmed in vivo, the compiled data show many intriguing properties of vinyl-ether bonded lipids that may play a significant role in the structural and morphological changes of the biomembranes. In this review, we present the current limited knowledge of the emerging potential role of plasmalogens as a modulator of the biomembrane morphology.
Collapse
Affiliation(s)
- Zakaria A Almsherqi
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
17
|
Ganichkin OM, Vancraenenbroeck R, Rosenblum G, Hofmann H, Mikhailov AS, Daumke O, Noel JK. Quantification and demonstration of the collective constriction-by-ratchet mechanism in the dynamin molecular motor. Proc Natl Acad Sci U S A 2021; 118:e2101144118. [PMID: 34244431 DOI: 10.1073/pnas.2101144118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Dynamin is a protein that is a central player in endocytosis, a process that mediates the entry of diverse particles into cells, from nutrients to viruses. Dynamin’s primary activity is to use guanosine triphosphate as fuel to constrict and cut membrane tubes. Key quantitative aspects of its function remain yet unclear. In this work, we determine the strength of an individual dynamin motor. Then, by building a detailed computational model resolving individual motors, we demonstrate that dynamin produces sufficient force to tightly constrict a membrane tube when most of its motors are simultaneously cooperating. Hence, we quantitatively validate the prevailing constriction-by-ratchet model for nature’s strongest torque-generating motor: the dynamin “nanomuscle.” Dynamin oligomerizes into helical filaments on tubular membrane templates and, through constriction, cleaves them in a GTPase-driven way. Structural observations of GTP-dependent cross-bridges between neighboring filament turns have led to the suggestion that dynamin operates as a molecular ratchet motor. However, the proof of such mechanism remains absent. Particularly, it is not known whether a powerful enough stroke is produced and how the motor modules would cooperate in the constriction process. Here, we characterized the dynamin motor modules by single-molecule Förster resonance energy transfer (smFRET) and found strong nucleotide-dependent conformational preferences. Integrating smFRET with molecular dynamics simulations allowed us to estimate the forces generated in a power stroke. Subsequently, the quantitative force data and the measured kinetics of the GTPase cycle were incorporated into a model including both a dynamin filament, with explicit motor cross-bridges, and a realistic deformable membrane template. In our simulations, collective constriction of the membrane by dynamin motor modules, based on the ratchet mechanism, is directly reproduced and analyzed. Functional parallels between the dynamin system and actomyosin in the muscle are seen. Through concerted action of the motors, tight membrane constriction to the hemifission radius can be reached. Our experimental and computational study provides an example of how collective motor action in megadalton molecular assemblies can be approached and explicitly resolved.
Collapse
|
18
|
Niko Y, Klymchenko AS. Emerging Solvatochromic Push-Pull Dyes for Monitoring the Lipid Order of Biomembranes in Live Cells. J Biochem 2021; 170:163-174. [PMID: 34213537 DOI: 10.1093/jb/mvab078] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/21/2021] [Indexed: 11/13/2022] Open
Abstract
Solvatochromic dyes have emerged as a new class of fluorescent probes in the field of lipid membranes due to their ability to identify the lipid organization of biomembranes in live cells by changing the color of their fluorescence. This type of solvatochromic function is useful for studying the heterogeneous features of biomembranes caused by the uneven distribution of lipids and cholesterols in live cells and related cellular processes. Therefore, a variety of advanced solvatochromic dyes have been rapidly developed over the last decade. To provide an overview of the works recently developed solvatochromic dyes have enabled, we herein present some solvatochromic dyes, with a particular focus on those based on pyrene and Nile red. As these dyes exhibit preferable photophysical properties in terms of fluorescence microscopy applications and unique distribution/localization in cellular compartments, some have already found applications in cell biological and biophysical studies. The goal of this review is to provide information to researchers who have never used solvatochromic dyes or who have not discovered applications of such dyes in biological studies.
Collapse
Affiliation(s)
- Yosuke Niko
- Research and Education Faculty, Multidisciplinary Science Cluster, Interdisciplinary Science Unit, Kochi University, 2-5-1, Akebono-cho, Kochi-shi, Kochi, 780-8520, Japan
| | - Andrey S Klymchenko
- Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Université de Strasbourg, 74 route du Rhin, 67401, Illkirch, France
| |
Collapse
|
19
|
Kleinwächter IS, Pannwitt S, Centi A, Hellmann N, Thines E, Bereau T, Schneider D. The Bacteriostatic Activity of 2-Phenylethanol Derivatives Correlates with Membrane Binding Affinity. Membranes (Basel) 2021; 11:membranes11040254. [PMID: 33807437 PMCID: PMC8067230 DOI: 10.3390/membranes11040254] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/25/2021] [Accepted: 03/26/2021] [Indexed: 11/16/2022]
Abstract
The hydrophobic tails of aliphatic primary alcohols do insert into the hydrophobic core of a lipid bilayer. Thereby, they disrupt hydrophobic interactions between the lipid molecules, resulting in a decreased lipid order, i.e., an increased membrane fluidity. While aromatic alcohols, such as 2-phenylethanol, also insert into lipid bilayers and disturb the membrane organization, the impact of aromatic alcohols on the structure of biological membranes, as well as the potential physiological implication of membrane incorporation has only been studied to a limited extent. Although diverse targets are discussed to be causing the bacteriostatic and bactericidal activity of 2-phenylethanol, it is clear that 2-phenylethanol severely affects the structure of biomembranes, which has been linked to its bacteriostatic activity. Yet, in fungi some 2-phenylethanol derivatives are also produced, some of which appear to also have bacteriostatic activities. We showed that the 2-phenylethanol derivatives phenylacetic acid, phenyllactic acid, and methyl phenylacetate, but not Tyrosol, were fully incorporated into model membranes and affected the membrane organization. Furthermore, we observed that the propensity of the herein-analyzed molecules to partition into biomembranes positively correlated with their respective bacteriostatic activity, which clearly linked the bacteriotoxic activity of the substances to biomembranes.
Collapse
Affiliation(s)
- Isabel S. Kleinwächter
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
| | - Stefanie Pannwitt
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
| | - Alessia Centi
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany; (A.C.); (T.B.)
| | - Nadja Hellmann
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
| | - Eckhard Thines
- Institute of Molecular Physiology, Johannes Gutenberg University, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany;
| | - Tristan Bereau
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany; (A.C.); (T.B.)
- Van ‘t Hoff Institute for Molecular Sciences and Informatics Institute, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Dirk Schneider
- Department of Chemistry, Biochemistry, Johannes Gutenberg University Mainz, Hanns-Dieter-Hüsch-Weg 17, 55128 Mainz, Germany; (I.S.K.); (S.P.); (N.H.)
- Max Planck Institute for Polymer Research, 55128 Mainz, Germany; (A.C.); (T.B.)
- Correspondence: ; Tel.: +49-6131-39-25833; Fax: +49-6131-39-25348
| |
Collapse
|
20
|
Moreno MJ, Teles Martins PA, Bernardino EF, Abel B, Ambudkar SV. Characterization of the Lipidome and Biophysical Properties of Membranes from High Five Insect Cells Expressing Mouse P-Glycoprotein. Biomolecules 2021; 11:biom11030426. [PMID: 33799403 PMCID: PMC8001469 DOI: 10.3390/biom11030426] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/11/2021] [Accepted: 03/12/2021] [Indexed: 12/31/2022] Open
Abstract
The lipid composition of biomembranes influences the properties of the lipid bilayer and that of the proteins. In this study, the lipidome and the lipid/protein ratio of membranes from High Five™ insect cells overexpressing mouse P-glycoprotein was characterized. This provides a better understanding of the lipid environment in which P-glycoprotein is embedded, and thus of its functional and structural properties. The relative abundance of the distinct phospholipid classes and their acyl chain composition was characterized. A mass ratio of 0.57 ± 0.11 phospholipids to protein was obtained. Phosphatidylethanolamines are the most abundant phospholipids, followed by phosphatidylcholines. Membranes are also enriched in negatively charged lipids (phosphatidylserines, phosphatidylinositols and phosphatidylglycerols), and contain small amounts of sphingomyelins, ceramides and monoglycosilatedceramides. The most abundant acyl chains are monounsaturated, with significant amounts of saturated chains. The characterization of the phospholipids by HPLC-MS allowed identification of the combination of acyl chains, with palmitoyl-oleoyl being the most representative for all major phospholipid classes except for phosphatidylserines, which are mostly saturated. A mixture of POPE:POPC:POPS in the ratio 45:35:20 is proposed for the preparation of simple representative model membranes. The adequacy of the model membranes was further evaluated by characterizing their surface potential and fluidity.
Collapse
Affiliation(s)
- Maria João Moreno
- Coimbra Chemistry Center, Chemistry Department, FCTUC, University of Coimbra, 3004-535 Coimbra, Portugal; (P.A.T.M.); (E.F.B.)
- CNC—Center for Neuroscience and Cell Biology, University of Coimbra, 3004-535 Coimbra, Portugal
- Correspondence:
| | | | - Eva F. Bernardino
- Coimbra Chemistry Center, Chemistry Department, FCTUC, University of Coimbra, 3004-535 Coimbra, Portugal; (P.A.T.M.); (E.F.B.)
| | - Biebele Abel
- Laboratory of Cell Biology, CCR, National Cancer Institute, NIH, Bethesda, MD 20892, USA; (B.A.); (S.V.A.)
| | - Suresh V. Ambudkar
- Laboratory of Cell Biology, CCR, National Cancer Institute, NIH, Bethesda, MD 20892, USA; (B.A.); (S.V.A.)
| |
Collapse
|
21
|
Hernández-Cáceres MP, Munoz L, Pradenas JM, Pena F, Lagos P, Aceiton P, Owen GI, Morselli E, Criollo A, Ravasio A, Bertocchi C. Mechanobiology of Autophagy: The Unexplored Side of Cancer. Front Oncol 2021; 11:632956. [PMID: 33718218 PMCID: PMC7952994 DOI: 10.3389/fonc.2021.632956] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
Proper execution of cellular function, maintenance of cellular homeostasis and cell survival depend on functional integration of cellular processes and correct orchestration of cellular responses to stresses. Cancer transformation is a common negative consequence of mismanagement of coordinated response by the cell. In this scenario, by maintaining the balance among synthesis, degradation, and recycling of cytosolic components including proteins, lipids, and organelles the process of autophagy plays a central role. Several environmental stresses activate autophagy, among those hypoxia, DNA damage, inflammation, and metabolic challenges such as starvation. In addition to these chemical challenges, there is a requirement for cells to cope with mechanical stresses stemming from their microenvironment. Cells accomplish this task by activating an intrinsic mechanical response mediated by cytoskeleton active processes and through mechanosensitive protein complexes which interface the cells with their mechano-environment. Despite autophagy and cell mechanics being known to play crucial transforming roles during oncogenesis and malignant progression their interplay is largely overlooked. In this review, we highlight the role of physical forces in autophagy regulation and their potential implications in both physiological as well as pathological conditions. By taking a mechanical perspective, we wish to stimulate novel questions to further the investigation of the mechanical requirements of autophagy and appreciate the extent to which mechanical signals affect this process.
Collapse
Affiliation(s)
- Maria Paz Hernández-Cáceres
- Laboratory of Autophagy and Metabolism, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile
| | - Leslie Munoz
- Laboratory for Mechanobiology of Transforming Systems, Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile
| | - Javiera M Pradenas
- Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile.,Laboratory of Investigation in Oncology, Faculty of Biological Sciences Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Francisco Pena
- Laboratory for Mechanobiology of Transforming Systems, Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile
| | - Pablo Lagos
- Laboratory of Autophagy and Metabolism, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile
| | - Pablo Aceiton
- Laboratory for Mechanobiology of Transforming Systems, Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile.,Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile
| | - Gareth I Owen
- Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile.,Laboratory of Investigation in Oncology, Faculty of Biological Sciences Pontificia Universidad Católica de Chile, Santiago, Chile.,Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Eugenia Morselli
- Laboratory of Autophagy and Metabolism, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile.,Autophagy Research Center, Santiago de Chile, Chile
| | - Alfredo Criollo
- Advanced Center for Chronic Diseases (ACCDiS), Santiago, Chile.,Autophagy Research Center, Santiago de Chile, Chile.,Facultad De Odontología, Instituto De Investigación En Ciencias Odontológicas (ICOD), Universidad De Chile, Santiago, Chile
| | - Andrea Ravasio
- Laboratory for Mechanobiology of Transforming Systems, Institute for Biological and Medical Engineering, Schools of Engineering, Medicine and Biological Sciences, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Cristina Bertocchi
- Laboratory for Molecular Mechanics of Cell Adhesion, Department of Physiology, Faculty of Biological Sciences, Pontificia Universidad Católica De Chile, Santiago, Chile
| |
Collapse
|
22
|
Ramos-Martín F, Herrera-León C, Antonietti V, Sonnet P, Sarazin C, D'Amelio N. Antimicrobial Peptide K11 Selectively Recognizes Bacterial Biomimetic Membranes and Acts by Twisting Their Bilayers. Pharmaceuticals (Basel) 2020; 14:1. [PMID: 33374932 DOI: 10.3390/ph14010001] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/14/2020] [Accepted: 12/19/2020] [Indexed: 12/14/2022] Open
Abstract
K11 is a synthetic peptide originating from the introduction of a lysine residue in position 11 within the sequence of a rationally designed antibacterial scaffold. Despite its remarkable antibacterial properties towards many ESKAPE bacteria and its optimal therapeutic index (320), a detailed description of its mechanism of action is missing. As most antimicrobial peptides act by destabilizing the membranes of the target organisms, we investigated the interaction of K11 with biomimetic membranes of various phospholipid compositions by liquid and solid-state NMR. Our data show that K11 can selectively destabilize bacterial biomimetic membranes and torque the surface of their bilayers. The same is observed for membranes containing other negatively charged phospholipids which might suggest additional biological activities. Molecular dynamic simulations reveal that K11 can penetrate the membrane in four steps: after binding to phosphate groups by means of the lysine residue at the N-terminus (anchoring), three couples of lysine residues act subsequently to exert a torque in the membrane (twisting) which allows the insertion of aromatic side chains at both termini (insertion) eventually leading to the flip of the amphipathic helix inside the bilayer core (helix flip and internalization).
Collapse
|
23
|
Ashrafi Z, Lucia L, Krause W. Underwater Superoleophobic Matrix-Formatted Liquid-Infused Porous Biomembranes for Extremely Efficient Deconstitution of Nanoemulsions. ACS Appl Mater Interfaces 2020; 12:50996-51006. [PMID: 33119268 DOI: 10.1021/acsami.0c13718] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Wettability is one of the most critical interfacial properties of any surface. Surfaces with special wettability such as superwetting or superantiwetting are being intensively explored for their wide-ranging applicability by a biomimetic exploration of unusual wetting phenomena in nature. This study provides a green water-infused superoleophobic composite membrane by boosting bacteria nanocellulose growth on a reinforcement fibrous substrate. It was shown that this versatile antifouling membrane is capable of removing water from surfactant-stabilized oil-in-water micro/nanoemulsions and helps to isolate the oil fraction with very high filtration efficiency. The renewable membrane based on bacteria nanocellulose matrices can vastly improve current technologies by cultivating a naturally occurring soft materials approach with lubricious conformal interfaces to effectively and simply cover suitable surfaces.
Collapse
Affiliation(s)
- Zahra Ashrafi
- Fiber and Polymer Science, NC State University, Campus Box 7616, Raleigh, North Carolina 27695, United States
| | - Lucian Lucia
- Fiber and Polymer Science, NC State University, Campus Box 7616, Raleigh, North Carolina 27695, United States
- Department of Forest Biomaterial, NC State University, Campus Box 8005, Raleigh, North Carolina 27695, United States
- Department of Chemistry, NC State University, Campus Box 8204, Raleigh, North Carolina 27695, United States
- State Key Laboratory of Bio-Based Materials & Green Papermaking, Qilu University of Technology/Shandong Academy of Sciences, Jinan 250353, PR China
| | - Wendy Krause
- Fiber and Polymer Science, NC State University, Campus Box 7616, Raleigh, North Carolina 27695, United States
| |
Collapse
|
24
|
Rademacher M, Kuhn H, Borchert A. Systemic deficiency of mouse arachidonate 15-lipoxygenase induces defective erythropoiesis and transgenic expression of the human enzyme rescues this phenotype. FASEB J 2020; 34:14318-14335. [PMID: 32918502 DOI: 10.1096/fj.202000408rr] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 07/29/2020] [Accepted: 08/07/2020] [Indexed: 02/06/2023]
Abstract
Arachidonic acid 15-lipoxygenases (ALOX15) are lipid peroxidizing enzymes, which has previously been implicated in the maturational breakdown of intracellular organelles and plasma membrane remodeling during reticulocyte-erythrocyte transition. Conventional Alox15-/- mice are viable, develop normally but do not exhibit a major defective erythropoietic phenotype. To characterize the putative in vivo relevance of Alox15 for red blood cell development, we explored the impact of systemic inactivation of the Alox15 gene on mouse erythropoiesis. We found that Alox15-/- mice exhibited reduced erythrocyte counts, elevated reticulocyte counts and red cell hyperchromia. The structure of the plasma membrane of Alox15-/- erythrocytes is altered and a significant share of the red cells was present as echinocytes and/or acanthocytes. An increased share of the Alox15-/- erythrocytes cells were annexin V positive, which indicates a loss of plasma membrane asymmetry. Erythrocytes of Alox15-/- mice were more susceptible to osmotic hemolysis and exhibited a reduced ex vivo life span. When we transgenically expressed human ALOX15 in Alox15-/- mice under the control of the aP2 promoter the defective erythropoietic system was rescued and the impaired osmotic resistance was normalized. Together these data suggest the involvement Alox15 in the maturational remodeling of the plasma membrane during red cell development.
Collapse
Affiliation(s)
- Marlena Rademacher
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Berlin, Germany
| | - Hartmut Kuhn
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Berlin, Germany
| | - Astrid Borchert
- Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Berlin, Germany
| |
Collapse
|
25
|
Lasitza-Male T, Bartels K, Jungwirth J, Wiggers F, Rosenblum G, Hofmann H, Löw C. Membrane Chemistry Tunes the Structure of a Peptide Transporter. Angew Chem Int Ed Engl 2020; 59:19121-19128. [PMID: 32744783 PMCID: PMC7590137 DOI: 10.1002/anie.202008226] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Indexed: 01/02/2023]
Abstract
Membrane proteins require lipid bilayers for function. While lipid compositions reach enormous complexities, high‐resolution structures are usually obtained in artificial detergents. To understand whether and how lipids guide membrane protein function, we use single‐molecule FRET to probe the dynamics of DtpA, a member of the proton‐coupled oligopeptide transporter (POT) family, in various lipid environments. We show that detergents trap DtpA in a dynamic ensemble with cytoplasmic opening. Only reconstitutions in more native environments restore cooperativity, allowing an opening to the extracellular side and a sampling of all relevant states. Bilayer compositions tune the abundance of these states. A novel state with an extreme cytoplasmic opening is accessible in bilayers with anionic head groups. Hence, chemical diversity of membranes translates into structural diversity, with the current POT structures only sampling a portion of the full structural space.
Collapse
Affiliation(s)
- Tanya Lasitza-Male
- Department of Structural Biology, Weizmann Institute of Science, Herzl St. 234, 7610001, Rehovot, Israel
| | - Kim Bartels
- Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Notkestrasse 85, 22607, Hamburg, Germany
| | - Jakub Jungwirth
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Herzl St. 234, 7610001, Rehovot, Israel
| | - Felix Wiggers
- Department of Structural Biology, Weizmann Institute of Science, Herzl St. 234, 7610001, Rehovot, Israel
| | - Gabriel Rosenblum
- Department of Structural Biology, Weizmann Institute of Science, Herzl St. 234, 7610001, Rehovot, Israel
| | - Hagen Hofmann
- Department of Structural Biology, Weizmann Institute of Science, Herzl St. 234, 7610001, Rehovot, Israel
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), DESY and European Molecular Biology Laboratory Hamburg, Notkestrasse 85, 22607, Hamburg, Germany.,Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden
| |
Collapse
|
26
|
Nickels JD, Poudel S, Chatterjee S, Farmer A, Cordner D, Campagna SR, Giannone RJ, Hettich RL, Myles DAA, Standaert RF, Katsaras J, Elkins JG. Impact of Fatty-Acid Labeling of Bacillus subtilis Membranes on the Cellular Lipidome and Proteome. Front Microbiol 2020; 11:914. [PMID: 32499768 PMCID: PMC7243436 DOI: 10.3389/fmicb.2020.00914] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 04/17/2020] [Indexed: 12/22/2022] Open
Abstract
Developing cultivation methods that yield chemically and isotopically defined fatty acid (FA) compositions within bacterial cytoplasmic membranes establishes an in vivo experimental platform to study membrane biophysics and cell membrane regulation using novel approaches. Yet before fully realizing the potential of this method, it is prudent to understand the systemic changes in cells induced by the labeling procedure itself. In this work, analysis of cellular membrane compositions was paired with proteomics to assess how the proteome changes in response to the directed incorporation of exogenous FAs into the membrane of Bacillus subtilis. Key findings from this analysis include an alteration in lipid headgroup distribution, with an increase in phosphatidylglycerol lipids and decrease in phosphatidylethanolamine lipids, possibly providing a fluidizing effect on the cell membrane in response to the induced change in membrane composition. Changes in the abundance of enzymes involved in FA biosynthesis and degradation are observed; along with changes in abundance of cell wall enzymes and isoprenoid lipid production. The observed changes may influence membrane organization, and indeed the well-known lipid raft-associated protein flotillin was found to be substantially down-regulated in the labeled cells – as was the actin-like protein MreB. Taken as a whole, this study provides a greater depth of understanding for this important cell membrane experimental platform and presents a number of new connections to be explored in regard to modulating cell membrane FA composition and its effects on lipid headgroup and raft/cytoskeletal associated proteins.
Collapse
Affiliation(s)
- Jonathan D Nickels
- Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH, United States
| | - Suresh Poudel
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Sneha Chatterjee
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Abigail Farmer
- Department of Chemistry, The University of Tennessee, Knoxville, Knoxville, TN, United States.,Biological and Small Molecule Mass Spectrometry Core, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Destini Cordner
- Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH, United States
| | - Shawn R Campagna
- Department of Chemistry, The University of Tennessee, Knoxville, Knoxville, TN, United States.,Biological and Small Molecule Mass Spectrometry Core, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - Richard J Giannone
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Robert L Hettich
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Dean A A Myles
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States
| | - Robert F Standaert
- Department of Chemistry, East Tennessee State University, Johnson City, TN, United States
| | - John Katsaras
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Shull Wollan Center - a Joint Institute for Neutron Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Department of Physics and Astronomy, The University of Tennessee, Knoxville, Knoxville, TN, United States
| | - James G Elkins
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, United States.,Department of Microbiology, The University of Tennessee, Knoxville, Knoxville, TN, United States
| |
Collapse
|
27
|
Sarmento MJ, Hof M, Šachl R. Interleaflet Coupling of Lipid Nanodomains - Insights From in vitro Systems. Front Cell Dev Biol 2020; 8:284. [PMID: 32411705 PMCID: PMC7198703 DOI: 10.3389/fcell.2020.00284] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/02/2020] [Indexed: 01/09/2023] Open
Abstract
The plasma membrane is a complex system, consisting of two layers of lipids and proteins compartmentalized into small structures called nanodomains. Despite the asymmetric composition of both leaflets, coupling between the layers is surprisingly strong. This can be evidenced, for example, by recent experimental studies performed on phospholipid giant unilamellar vesicles showing that nanodomains formed in the outer layer are perfectly registered with those in the inner leaflet. Similarly, microscopic phase separation in one leaflet can induce phase separation in the opposing leaflet that would otherwise be homogeneous. In this review, we summarize the current theoretical and experimental knowledge that led to the current view that domains are – irrespective of their size – commonly registered across the bilayer. Mechanisms inducing registration of nanodomains suggested by theory and calculations are discussed. Furthermore, domain coupling is evidenced by experimental studies based on the sparse number of methods that can resolve registered from independent nanodomains. Finally, implications that those findings using model membrane studies might have for cellular membranes are discussed.
Collapse
Affiliation(s)
- Maria J Sarmento
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova, Prague, Czechia
| | - Martin Hof
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova, Prague, Czechia
| | - Radek Šachl
- J. Heyrovský Institute of Physical Chemistry of the Czech Academy of Sciences, Dolejškova, Prague, Czechia
| |
Collapse
|
28
|
Luchini A, Vitiello G. Understanding the Nano-bio Interfaces: Lipid-Coatings for Inorganic Nanoparticles as Promising Strategy for Biomedical Applications. Front Chem 2019; 7:343. [PMID: 31165058 PMCID: PMC6534186 DOI: 10.3389/fchem.2019.00343] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 04/25/2019] [Indexed: 12/26/2022] Open
Abstract
Inorganic nanoparticles (NPs) exhibit relevant physical properties for application in biomedicine and specifically for both the diagnosis and therapy (i.e. theranostic) of severe pathologies, such as cancer. The inorganic NP core is often not stable in aqueous suspension and can induce cytotoxic effects. For this reason, over the years, several coating strategies were suggested to improve the NP stability in aqueous solutions as well as the NP biocompatibility. Among the various components which can be used for NP coatings, lipids, and in particular phospholipids emerged as versatile molecular building blocks for the production of NP coatings suitable for biomedical application. The recent synthetic efforts in NP lipid coatings allows today to introduce on the NP surface a large variety of lipid molecules eventually in mixture with amphiphilic or hydrophobic drugs or active molecules for cell targeting. In this review, the most relevant examples of NP lipid-coatings are presented and grouped in two main categories: supported lipid bilayers (SLB) and hybrid lipid bilayers (HLB). The discussed scientific cases take into account the most commonly used inorganic NP for biomedical applications in cancer therapy and diagnosis.
Collapse
Affiliation(s)
| | - Giuseppe Vitiello
- Department of Chemical, Materials and Production Engineering, University of Naples Federico II, Naples, Italy
- CSGI, Center for Colloids and Surface Science, Sesto Fiorentino, Italy
| |
Collapse
|
29
|
Almansour M, Alarifi S, Melhim W, Jarrar BM. Nephron ultrastructural alterations induced by zinc oxide nanoparticles: an electron microscopic study. IET Nanobiotechnol 2019; 13:515-521. [PMCID: PMC8676027 DOI: 10.1049/iet-nbt.2018.5219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 01/26/2019] [Accepted: 02/13/2019] [Indexed: 09/05/2023] Open
Abstract
Due to their unique properties, zinc oxide nanoparticles (ZnO NPs) are invested in many industries, commercial products, and nanomedicine with potential risk for human health and the environment. The present study aims to focus on alterations that might be induced by ZnO NPs in the nephron ultrastructure. Male Wister Albino rats were subjected to ZnO NPs at a daily dose of 2 mg/kg for 21 days. Kidney biopsies were processed to transmission electron microscopy (TEM) and ultrastructural pathology examinations. Exposure to ZnO NPs‐induced ultrastructural alterations in the proximal convoluted tubules (PCTs) and to lesser extent in the distal ones (DCTs), while the loops of Henle were almost not affected. The glomeruli demonstrated dilatation, partial mesangial cells loss, matrix ballooning, slits filtration widening, and basement membrane thickening. Moreover, PCT revealed cytoplasmic necrosis, vacuolation, erosion, and disorganisation of the apical microvilli together with mitochondrial swelling and cristae destruction. The nuclei of the renal cells exhibited nuclear deformity, heterochromatin accumulation, and apoptotic activities. The findings indicate that ZnO nanomaterial have the potential to affect the nephron ultrastructure suggesting alteration in the kidney functions. More work is needed for better understanding the toxicity and pathogenesis of ZnO oxide nanomaterial.
Collapse
Affiliation(s)
- Mansour Almansour
- Zoology DepartmentCollege of ScienceKing Saud UniversitySaudi Arabia
| | - Saud Alarifi
- Zoology DepartmentCollege of ScienceKing Saud UniversitySaudi Arabia
| | - Walid Melhim
- Electron Microscopy UnitCollege of MedicineKing Faisal UniversitySaudi Arabia
| | - Bashir M. Jarrar
- Department of Biological SciencesCollege of ScienceJerash UniversityJordan
| |
Collapse
|
30
|
Abstract
Exogenous fluorescent materials activated by near-infrared (NIR) light can offer deep optical imaging with subcellular resolution, and enhanced image contrast. We have engineered NIR particles by doping hemoglobin-depleted erythrocyte ghosts (EGs) with indocyanine green (ICG). We refer to these optical particles as NIR erythrocyte-mimicking transducers (NETs). A particular feature of NETs is that their diameters can be tuned from micrometer to nanometer scale, thereby, providing a capability for broad NIR biomedical imaging applications. Herein, we investigate the effects of ICG concentration on key material properties of micrometer-sized NETs, and nanometer-sized NETs fabricated by either sonication or mechanical extrusion of EGs. The zeta potentials of NETs do not vary significantly with ICG concentration, suggesting that ICG is encapsulated within NETs regardless of particle size or ICG concentration. Loading efficiency of ICG into the NETs monotonically decreases with increasing values of ICG concentration. Based on quantitative analyses of the fluorescence emission spectra of the NETs, we determine that 20 μM ICG utilized during fabrication of NETs presents an optimal concentration that maximizes the integrated fluorescence emission for micrometer- and nanometer-sized NETs. Encapsulation of the ICG in these constructs also enhances the fluorescence stability and quantum yield of ICG. These results guide the engineering of NETs with maximal NIR emission for imaging applications such as fluorescence-guided tumor resection and real-time angiography.
Collapse
|
31
|
Tetsworth K, Woloszyk A, Glatt V. 3D printed titanium cages combined with the Masquelet technique for the reconstruction of segmental femoral defects: Preliminary clinical results and molecular analysis of the biological activity of human-induced membranes. OTA Int 2019; 2:e016. [PMID: 33937652 PMCID: PMC7953522 DOI: 10.1097/oi9.0000000000000016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Accepted: 09/24/2018] [Indexed: 11/25/2022]
Abstract
Introduction: Traumatic femoral segmental bone loss is a complex clinical problem, one that often requires extreme solutions. This study examines a new treatment strategy for segmental bone loss using patient-specific 3D printed titanium cages in conjunction with the Masquelet technique. Methods: The study was composed of a clinical observational case series, and a basic science investigation to evaluate the biological activity of the induced membranes using histology, immunohistochemistry (IHC), and gene expression analysis. Eligible patients were: adult; post-traumatic; with segmental femoral defects; minimum follow-up 1 year; managed under a 2-stage protocol, with an interim antibiotic poly (methyl methacrylate) (PMMA) spacer. Definitive reconstruction was completed with exchange to a 3D printed custom titanium cage filled with bone graft, and stabilized with either an intramedullary (IM) nail or a lateral locked plate. Results: Patient-specific 3D printed titanium cages were used in 5 consecutive patients to reconstruct post-traumatic segmental femoral defects. The mean interval between stages was 100.2 days (83–119 days), the mean defect length was 14.0 cm (10.3–18.4 cm), and the mean bone defect volume measured 192.4 cc (114–292 cc). The mean length of follow-up was 21.8 months (12–33 months). There were no deep infections, fractures, nerve injuries, loss of alignment, or nonunions identified during the period of follow-up. All of the patients achieved union clinically and radiographically. Histology and IHC demonstrated a greater number of vessels, cell nuclei, and extensive staining for cluster of differentiation 68 (CD68), platelet and endothelial cell adhesion molecule 1 (PECAM-1), and vascular endothelial growth factor (VEGF) in the induced membranes compared to local fascia controls. Gene expression analysis revealed significant differential regulation of essential genes involved in inflammatory, angiogenic, and osteogenic pathways [interleukin 6 (IL-6), nuclear factor kappa B1 (NF-κB1), receptor activator of nuclear factor kappa-β ligand (RANKL), vascular endothelial growth factor A (VEGFA), angiogenin (ANG), transforming growth factor, beta 1 (TGF-β1), bone morphogenetic protein-2 (BMP-2), growth differentiation factor 5 (GDF-5), growth differentiation factor 10 (GDF-10), and runt-related transcription factor 2 (RUNX-2)] in the induced membranes. Conclusions: This study demonstrates that the use of a patient-specific 3D printed custom titanium cage, inserted into an induced membrane in a 2-stage protocol, can achieve very acceptable clinical outcomes in selected cases of post-traumatic femoral segmental defects. Patient-specific 3D printed titanium cages, used in conjunction with the Masquelet technique, are a promising new treatment option for managing complex trauma patients with femoral bone loss. Level of Evidence: Level IV (observational case series).
Collapse
Affiliation(s)
- Kevin Tetsworth
- Royal Brisbane and Women's Hospital, Herston, Queensland.,Orthopaedic Research Centre of Australia, Brisbane, Queensland, Australia
| | - Anna Woloszyk
- Department of Orthopedic Surgery, University of Texas Health Science Center San Antonio, Texas
| | - Vaida Glatt
- Orthopaedic Research Centre of Australia, Brisbane, Queensland, Australia.,Department of Orthopedic Surgery, University of Texas Health Science Center San Antonio, Texas
| |
Collapse
|
32
|
Uchida N, Nishizawa Horimoto N, Yamada K, Hikima T, Ishida Y. Kinetically Stable Bicelles with Dilution Tolerance, Size Tunability, and Thermoresponsiveness for Drug Delivery Applications. Chembiochem 2018; 19:1922-1926. [PMID: 29969169 DOI: 10.1002/cbic.201800304] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Indexed: 11/10/2022]
Abstract
Mixtures of a phospholipid (1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine, DPPC) and a sodium-cholate-derived surfactant (SC-C5 ) at room temperature formed phospholipid bilayer fragments that were edge-stabilized by SC-C5 : so-called "bicelles". Because the bilayer melting point of DPPC (41 °C) is above room temperature and because SC-C5 has an exceptionally low critical micelle concentration (<0.5 mm), the bicelles are kinetically frozen at room temperature. Consequently, they exist even when the mixture is diluted to a concentration of 0.04 wt %. In addition, the lateral size of the bicelles can be fine-tuned by altering the molar ratio of DPPC to SC-C5 . On heating to ≈37 °C, the bicelles transformed into micelles composed of DPPC and SC-C5 . By taking advantage of the dilution tolerance, size tunability, and thermoresponsiveness, we demonstrated in vitro drug delivery based on use of the bicelles as carriers, which suggests their potential utility in transdermal drug delivery.
Collapse
Affiliation(s)
- Noriyuki Uchida
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | | | - Kuniyo Yamada
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| | - Takaaki Hikima
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo, 679-5148, Japan
| | - Yasuhiro Ishida
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan
| |
Collapse
|
33
|
Prabukumar S, Rajkuberan C, Sathishkumar G, Illaiyaraja M, Sivaramakrishnan S. One pot green fabrication of metallic silver nanoscale materials using Crescentia cujete L. and assessment of their bactericidal activity. IET Nanobiotechnol 2018; 12:505-508. [PMID: 29768238 PMCID: PMC8676202 DOI: 10.1049/iet-nbt.2017.0209] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 12/11/2017] [Accepted: 12/21/2017] [Indexed: 01/06/2024] Open
Abstract
In this study, the leaf extract of an important medicinal plant Crescentia cujete L. (CC) was employed as a green reducing agent to synthesise highly-stable C. cujete silver nanoparticles (CCAgNPs). The reduction of Ag+ to Ag0 nanoparticles was initially observed by a colour change which generates an intense surface plasmon resonance peak at 417 nm using a UV-Vis spectrophotometer. Various optimisation factors such as temperature, pH, time and the stoichiometric proportion of the reaction mixture were performed, which influence the size, dispersity and synthesis rate of CCAgNPs. In addition, surface chemistry of synthesised CCAgNPs through Fourier transform infrared spectroscopy reveals the reducing/stabilising agent present in the aqueous extract of C. cujete and synthesised CCAgNPs. Transmission electron microscopy analysis features the spherical shape of CCAgNPs with an average size of 39.74 nm. Furthermore, an X-ray diffraction study confirms that the synthesised CCAgNPs were face-centred cubic crystalline in nature. The CCAgNPs display tremendous bactericidal activity against human pathogens Bacillus subtilis, Staphylococcus epidermidis, Rhodococcus rhodochrous, Salmonella typhi, Mycobacterium smegmatis, Shigella flexneri and Vibrio cholerae via penetrating into the bacterial cell membrane and causing failure of an internal chain reaction.
Collapse
Affiliation(s)
- Seetharaman Prabukumar
- Department of Biotechnology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India
| | | | | | - Mani Illaiyaraja
- Department of Biotechnology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India
| | | |
Collapse
|
34
|
Abul Qais F, Samreen, Ahmad I. Broad‐spectrum inhibitory effect of green synthesised silver nanoparticles from Withania somnifera (L.) on microbial growth, biofilm and respiration: a putative mechanistic approach. IET Nanobiotechnol 2018; 12:325-335. [PMCID: PMC8676045 DOI: 10.1049/iet-nbt.2017.0193] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 11/14/2017] [Accepted: 11/21/2017] [Indexed: 09/05/2023] Open
Abstract
Multi‐drug resistance in pathogenic bacteria has created immense clinical problem globally. To address these, there is need to develop new therapeutic strategies to combat bacterial infections. Silver nanoparticles (AgNPs) might prove to be next generation nano‐antibiotics. However, improved efficacy and broad‐spectrum activity is still needed to be evaluated and understood. The authors have synthesised AgNPs from Withania somnifera (WS) by green process and characterised. The effect of WS‐AgNPs on growth kinetics, biofilm inhibition as well as eradication of preformed biofilms on both gram‐positive and gram‐negative pathogenic bacteria was evaluated. The authors have demonstrated the inhibitory effect on bacterial respiration and disruption of membrane permeability and integrity. It was found that WS‐AgNPs inhibited growth of pathogenic bacteria even at 16 µg/ml. At sub‐minimum inhibitory concentration concentration, there was approximately 50% inhibition in biofilm formation which was further validated by light and electron microscopy. WS‐AgNPs also eradicated the performed biofilms by varying levels at elevated concentration. The bacterial respiration was also significantly inhibited. Interaction of WS‐AgNPs with test pathogen caused the disruption of cell membrane leading to leakage of cellular content. The production of intracellular reactive oxygen species reveals that WS‐AgNPs exerted oxidative stress inside bacterial cell causing microbial growth inhibition and disrupting cellular functions.
Collapse
Affiliation(s)
- Faizan Abul Qais
- Department of Agricultural MicrobiologyAligarh Muslim UniversityAligarhUP202002India
| | - Samreen
- Department of Agricultural MicrobiologyAligarh Muslim UniversityAligarhUP202002India
| | - Iqbal Ahmad
- Department of Agricultural MicrobiologyAligarh Muslim UniversityAligarhUP202002India
| |
Collapse
|
35
|
Tetz GV, Artemenko NK, Yankovskii GM, Kever LV, Komissarchik YY, Tetz VV. Effects of Multicide, Antibacterial Drug, on Staphylococcus Biomembranes. Bull Exp Biol Med 2017; 163:780-784. [PMID: 29063334 DOI: 10.1007/s10517-017-3902-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Indexed: 11/28/2022]
Abstract
Drug penetration into bacterial biomembranes is one of the most important factors determining the efficiency of antibacterial therapy. Multicide, antibacterial drug, is a nanomolecule 1.3-2.0 nm in size, easily penetrating into staphylococcus biomembranes and causing rapid death of bacteria. The drug efficiency depends on its concentration and duration of exposure. Bacteria die as a result of cell wall perforation, which is associated with changes in its morphology and release of DNA from bacterial cell into the environment. Our results indicate the efficiency of primary damage to bacterial wall leading to elimination of biomembranes.
Collapse
Affiliation(s)
- G V Tetz
- Department of Microbiology and Virology, I. P. Pavlov St. Petersburg First State Medical University, the Ministry of Health of the Russian Federation, St. Petersburg, Russia
| | - N K Artemenko
- Department of Microbiology and Virology, I. P. Pavlov St. Petersburg First State Medical University, the Ministry of Health of the Russian Federation, St. Petersburg, Russia
| | - G M Yankovskii
- MISiS National Research Technological Institute, Moscow, Russia
| | - L V Kever
- Institute of Cytology, the Russian Academy of Sciences, St. Petersburg, Russia
| | - Ya Yu Komissarchik
- Institute of Cytology, the Russian Academy of Sciences, St. Petersburg, Russia
| | - V V Tetz
- Department of Microbiology and Virology, I. P. Pavlov St. Petersburg First State Medical University, the Ministry of Health of the Russian Federation, St. Petersburg, Russia.
| |
Collapse
|
36
|
Deike S, Malke M, Lechner BD, Binder WH. Constraining Polymers into β-Turns: Miscibility and Phase Segregation Effects in Lipid Monolayers. Polymers (Basel) 2017; 9:E369. [PMID: 30971043 PMCID: PMC6418963 DOI: 10.3390/polym9080369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 08/11/2017] [Accepted: 08/13/2017] [Indexed: 11/17/2022] Open
Abstract
Abstract: Investigation of model biomembranes and their interactions with natural or synthetic macromolecules are of great interest to design membrane systems with specific properties such as drug-delivery. Here we study the behavior of amphiphilic β-turn mimetic polymer conjugates at the air⁻water interface and their interactions with lipid model membranes. For this endeavor we synthesized two different types of conjugates containing either hydrophobic polyisobutylene (PIB, Mn = 5000 g·mol-1) or helical poly(n-hexyl isocyanate) (PHIC, Mn = 4000 g·mol-1), both polymers being immiscible, whereas polyisobutylene as a hydrophobic polymer can incorporate into lipid membranes. The conjugates were investigated using Langmuir-film techniques coupled with epifluorescence microscopy and AFM (Atomic Force Microscopy), in addition to their phase behavior in mixed lipid/polymer membranes composed of DPPC (dipalmitoyl-sn-glycero-3-phosphocholine). It was found that the DPPC monolayers are strongly disturbed by the presence of the polymer conjugates and that domain formation of the polymer conjugates occurs at high surface pressures (π > 30 mN·m-1).
Collapse
Affiliation(s)
- Stefanie Deike
- Faculty of Natural Science II, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| | - Marlen Malke
- Faculty of Natural Science II, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| | - Bob-Dan Lechner
- Faculty of Natural Science II, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
- School of Physics, University of Exeter, Stocker Road, Exeter EX4, UK.
| | - Wolfgang H Binder
- Faculty of Natural Science II, Martin Luther University Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany.
| |
Collapse
|
37
|
Oluwole AO, Danielczak B, Meister A, Babalola JO, Vargas C, Keller S. Solubilization of Membrane Proteins into Functional Lipid-Bilayer Nanodiscs Using a Diisobutylene/Maleic Acid Copolymer. Angew Chem Int Ed Engl 2017; 56:1919-1924. [PMID: 28079955 PMCID: PMC5299484 DOI: 10.1002/anie.201610778] [Citation(s) in RCA: 192] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 11/24/2016] [Indexed: 12/22/2022]
Abstract
Once removed from their natural environment, membrane proteins depend on membrane-mimetic systems to retain their native structures and functions. To this end, lipid-bilayer nanodiscs that are bounded by scaffold proteins or amphiphilic polymers such as styrene/maleic acid (SMA) copolymers have been introduced as alternatives to detergent micelles and liposomes for in vitro membrane-protein research. Herein, we show that an alternating diisobutylene/maleic acid (DIBMA) copolymer shows equal performance to SMA in solubilizing phospholipids, stabilizes an integral membrane enzyme in functional bilayer nanodiscs, and extracts proteins of various sizes directly from cellular membranes. Unlike aromatic SMA, aliphatic DIBMA has only a mild effect on lipid acyl-chain order, does not interfere with optical spectroscopy in the far-UV range, and does not precipitate in the presence of low millimolar concentrations of divalent cations.
Collapse
Affiliation(s)
- Abraham Olusegun Oluwole
- Molecular BiophysicsUniversity of KaiserslauternErwin-Schrödinger-Str. 1367663KaiserslauternGermany
- Department of ChemistryUniversity of Ibadan200284IbadanNigeria
| | - Bartholomäus Danielczak
- Molecular BiophysicsUniversity of KaiserslauternErwin-Schrödinger-Str. 1367663KaiserslauternGermany
| | - Annette Meister
- Institute of Chemistry and Institute of Biochemistry and BiotechnologyMartin Luther University Halle-WittenbergVon-Danckelmann-Platz 406120HalleGermany
| | | | - Carolyn Vargas
- Molecular BiophysicsUniversity of KaiserslauternErwin-Schrödinger-Str. 1367663KaiserslauternGermany
| | - Sandro Keller
- Molecular BiophysicsUniversity of KaiserslauternErwin-Schrödinger-Str. 1367663KaiserslauternGermany
| |
Collapse
|
38
|
Miller EJ, Trewby W, Farokh Payam A, Piantanida L, Cafolla C, Voïtchovsky K. Sub-nanometer Resolution Imaging with Amplitude-modulation Atomic Force Microscopy in Liquid. J Vis Exp 2016:54924. [PMID: 28060262 PMCID: PMC5226432 DOI: 10.3791/54924] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Atomic force microscopy (AFM) has become a well-established technique for nanoscale imaging of samples in air and in liquid. Recent studies have shown that when operated in amplitude-modulation (tapping) mode, atomic or molecular-level resolution images can be achieved over a wide range of soft and hard samples in liquid. In these situations, small oscillation amplitudes (SAM-AFM) enhance the resolution by exploiting the solvated liquid at the surface of the sample. Although the technique has been successfully applied across fields as diverse as materials science, biology and biophysics and surface chemistry, obtaining high-resolution images in liquid can still remain challenging for novice users. This is partly due to the large number of variables to control and optimize such as the choice of cantilever, the sample preparation, and the correct manipulation of the imaging parameters. Here, we present a protocol for achieving high-resolution images of hard and soft samples in fluid using SAM-AFM on a commercial instrument. Our goal is to provide a step-by-step practical guide to achieving high-resolution images, including the cleaning and preparation of the apparatus and the sample, the choice of cantilever and optimization of the imaging parameters. For each step, we explain the scientific rationale behind our choices to facilitate the adaptation of the methodology to every user's specific system.
Collapse
|
39
|
Hughes AV, Ciesielski F, Kalli AC, Clifton LA, Charlton TR, Sansom MSP, Webster JRP. On the interpretation of reflectivity data from lipid bilayers in terms of molecular-dynamics models. Acta Crystallogr D Struct Biol 2016; 72:1227-1240. [PMID: 27917824 DOI: 10.1107/s2059798316016235] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 10/12/2016] [Indexed: 02/08/2023]
Abstract
Neutron and X-ray reflectivity of model membranes is increasingly used as a tool for the study of membrane structures and dynamics. As the systems under study become more complex, and as long, all-atom molecular-dynamics (MD) simulations of membranes become more available, there is increasing interest in the use of MD simulations in the analysis of reflectometry data from membranes. In order to perform this, it is necessary to produce a model of the complete interface, including not only the MD-derived structure of the membrane, but also the supporting substrate and any other interfacial layers that may be present. Here, it is shown that this is best performed by first producing a model of the occupied volume across the entire interface, and then converting this into a scattering length density (SLD) profile, rather than by splicing together the separate SLD profiles from the substrate layers and the membrane, since the latter approach can lead to discontinuities in the SLD profile and subsequent artefacts in the reflectivity calculation. It is also shown how the MD-derived membrane structure should be corrected to account for lower than optimal coverage and out-of-plane membrane fluctuations. Finally, the method of including the entire membrane structure in the reflectivity calculation is compared with an alternative approach in which the membrane components are approximated by functional forms, with only the component volumes being extracted from the simulation. It is shown that using only the fragment volumes is insufficient for a typical neutron data set of a single deuteration measured at several water contrasts, and that either weighting the model by including more structural information from the fit, or a larger data set involving a range of deuterations, are required to satisfactorily define the problem.
Collapse
Affiliation(s)
- Arwel V Hughes
- ISIS Pulsed Neutron Source, Rutherford Appleton Laboratory, Harwell OX11 0QX, England
| | - Fillip Ciesielski
- ISIS Pulsed Neutron Source, Rutherford Appleton Laboratory, Harwell OX11 0QX, England
| | - Antreas C Kalli
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, England
| | - Luke A Clifton
- ISIS Pulsed Neutron Source, Rutherford Appleton Laboratory, Harwell OX11 0QX, England
| | - Timothy R Charlton
- ISIS Pulsed Neutron Source, Rutherford Appleton Laboratory, Harwell OX11 0QX, England
| | - Mark S P Sansom
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, England
| | - John R P Webster
- ISIS Pulsed Neutron Source, Rutherford Appleton Laboratory, Harwell OX11 0QX, England
| |
Collapse
|
40
|
Singh M. Elucidation of biogenic silver nanoparticles susceptibility towards Escherichia coli: an investigation on the antimicrobial mechanism. IET Nanobiotechnol 2016; 10:276-280. [PMID: 27676374 PMCID: PMC8676372 DOI: 10.1049/iet-nbt.2015.0063] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 11/30/2015] [Accepted: 12/08/2015] [Indexed: 01/06/2023] Open
Abstract
Elucidation of the role of silver nanoparticles (AgNPs) in combating bacterial infection is important for the development of new antimicrobial compounds. In this study, several key factors underlying biological effects of biogenic AgNPs were investigated on recombinant Escherichia coli (XL1-Blue) which contains a reporter gene encoding β-galactosidase enzyme. Biogenic AgNPs were prepared from the tea decoction. Cytotoxicity effects were profound on the bacteria tested by the synthesised NPs. The β-galactosidase activity of the released intracellular proteins in the supernatant of E. coli was used as a measure of membrane damage and cellular leakage. Occurrence of a significant amount of β-galactosiadase activity in the supernatant of treated cells clearly demonstrated the formation of holes in the bacterial membrane. Scanning electron microscope pictures visibly indicated destruction of the membrane of the bacteria, which further confirmed membrane damage. The synthesised NPs caused damage of E. coli genomic DNA in a dose dependent manner.
Collapse
Affiliation(s)
- Mukesh Singh
- Department of Biotechnology, Haldia Institute of Technology, HIT campus, Hatiberia, Purba Medinipur, Haldia 721 657, India.
| |
Collapse
|
41
|
David G, Pedrigi RM, Humphrey JD. Accommodation of the human lens capsule using a finite element model based on nonlinear regionally anisotropic biomembranes. Comput Methods Biomech Biomed Engin 2016; 20:302-307. [PMID: 27609339 DOI: 10.1080/10255842.2016.1228907] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Accommodation of the eyes, the mechanism that allows humans to focus their vision on near objects, naturally diminishes with age via presbyopia. People who have undergone cataract surgery, using current surgical methods and artificial lens implants, are also left without the ability to accommodate. The process of accommodation is generally well known; however the specific mechanical details have not been adequately explained due to difficulties and consequences of performing in vivo studies. Most studies have modeled the mechanics of accommodation under assumptions of a linearly elastic, isotropic, homogenous lens and lens capsule. Recent experimental and numerical studies showed that the lens capsule exhibits nonlinear elasticity and regional anisotropy. In this paper we present a numerical model of human accommodation using a membrane theory based finite element approach, incorporating recent findings on capsular properties. This study seeks to provide a novel perspective of the mechanics of accommodation. Such findings may prove significant in seeking biomedical solutions to restoring loss of visual power.
Collapse
Affiliation(s)
- G David
- a Institute of Mathematics , University of the Philippines , Quezon City , Philippines
| | - R M Pedrigi
- b Department of Bioengineering , Imperial College London , London , UK
| | - J D Humphrey
- c Department of Biomedical Engineering , Yale University , New Haven , CT , USA
| |
Collapse
|
42
|
Drvenica IT, Bukara KM, Ilić VL, Mišić DM, Vasić BZ, Gajić RB, Đorđević VB, Veljović ĐN, Belić A, Bugarski BM. Biomembranes from slaughterhouse blood erythrocytes as prolonged release systems for dexamethasone sodium phosphate. Biotechnol Prog 2016; 32:1046-55. [PMID: 27254304 DOI: 10.1002/btpr.2304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Revised: 02/02/2016] [Indexed: 01/04/2023]
Abstract
The present study investigated preparation of bovine and porcine erythrocyte membranes from slaughterhouse blood as bio-derived materials for delivery of dexamethasone-sodium phosphate (DexP). The obtained biomembranes, i.e., ghosts were characterized in vitro in terms of morphological properties, loading parameters, and release behavior. For the last two, an UHPLC/-HESI-MS/MS based analytical procedure for absolute drug identification and quantification was developed. The results revealed that loading of DexP into both type of ghosts was directly proportional to the increase of drug concentration in the incubation medium, while incubation at 37°C had statistically significant effect on loaded amount of DexP (P < 0.05). The encapsulation efficiency was about fivefold higher in porcine compared to bovine ghosts. Insight into ghosts' surface morphology by field emission-scanning electron microscopy and atomic force microscopy confirmed that besides inevitable effects of osmosis, DexP inclusion itself had no observable additional effect on the morphology of the ghosts carriers. DexP release profiles were dependent on erythrocyte ghost type and amount of residual hemoglobin. However, sustained DexP release was achieved and shown over 3 days from porcine ghosts and 5 days from bovine erythrocyte ghosts. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1046-1055, 2016.
Collapse
Affiliation(s)
- Ivana T Drvenica
- Dept. of Chemical Engineering, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| | - Katarina M Bukara
- Dept. of Chemical Engineering, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| | - Vesna Lj Ilić
- Inst. for Medical Research, University of Belgrade, Belgrade, Serbia
| | - Danijela M Mišić
- Inst. for Biological Research "Siniša Stanković,", University of Belgrade, Belgrade, Serbia
| | | | - Radoš B Gajić
- Inst. of Physics, University of Belgrade, Belgrade, Serbia
| | - Verica B Đorđević
- Dept. of Chemical Engineering, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| | - Đorđe N Veljović
- Dept. of Chemical Engineering, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| | | | - Branko M Bugarski
- Dept. of Chemical Engineering, Faculty of Technology and Metallurgy, University of Belgrade, Belgrade, Serbia
| |
Collapse
|
43
|
Abstract
Two methods of measuring the misorientation of domains in oriented multilamellar stacks of lipid bilayers superficially appeared to give different values for the mosaic spread. It is first shown that the traditional rocking method and a newer ring method give the same value of the mosaic spread when the two types of data are similarly analyzed. Both indicate a long-tailed, nearly Lorentzian, mosaic distribution function. Our primary innovation is the analysis of ring data as a function of the rocking angle. For our best oriented DOPC sample, this analysis is consistent with a single Lorentzian mosaic distribution function with width 0.05°. In contrast, samples of DMPC indicate a more complex mosaic distribution and larger widths.
Collapse
Affiliation(s)
- John F Nagle
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
| | | | | | | |
Collapse
|
44
|
Zhirnov VV, Iakovenko IN, Voitsitskiy VM, Khyzhnyak SV, Zubrikova-Chugainova OG, Gorobetz VA. Zeta potential response of human erythrocyte membranes to the modulators of Gardos channel activity under low rate β-radiation. Probl Radiac Med Radiobiol 2015; 20:490-499. [PMID: 26695925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/05/2015] [Indexed: 06/05/2023]
Abstract
OBJECTIVE Study of human erythrocyte DP response under modification by activators and blockers of the functional state of Ca2+-dependent K+ channels under low rate β-radiation. MATERIALS AND METHODS Erythrocytes were isolated from the donor blood. The zeta potential was computed from the value of the cell electrophoretic mobility. The investigated drugs preliminary introduced in cellular suspensions, and then aliquote of 90Sr(NO3)2 solution to get the final activity concentration of 44,4kBq⋅l-1. RESULTS The radioisotope radiation of 90Sr/90Y (RR, 15 μGy⋅h-1) increases an absolute value of erythrocyte membranes DP (DPab), and its action is reversible. It specifies the effect is mediated by non-ionizing part of the RR. Dibutyril-cAMP dose-independent increases DPab of erythrocyte membranes in the concentration range of 1-100 мкМ, but RR does not amplify this effect. Anaprilin increases dose-independent DPab in concentrations 10 and 100 μМ. The effect of maximal concentration of anaprilin (100 μМ) decreases by RR. Clotrimazol increases DPab of erythrocyte membranes in the concentration range of 0,1-10 μМ relatively control, while its maximal concentration - decreases, and the minimal level does not reliably influence on this index The action of сlotrimazol on DP in concentrations of 10-100 μМ is abolished by RR, and is not changed in the range of 0,1-1,0 μМ. Nitrendipine raises DPab of erythrocyte membranes in all of range of concentrations, and RR amplifies the effect of the drug. CONCLUSIONS 1. There is a threshold of the biological action on cells for the ionizing component of radioisotope radiation determined by efficiency of operation their antioxidant system.2. At dose rates below a threshold, the action of ionizing radiation is mediated by its non-ionizing component, and is reversible, and therefore is determined only in the field of radiation.
Collapse
Affiliation(s)
- V V Zhirnov
- Institute of Bioorganic Chemistry and Petrochemistry of National Academy of Sciences of Ukraine., 1 Murmanska St., Kyiv, 02660, Ukraine
| | - I N Iakovenko
- Institute of Bioorganic Chemistry and Petrochemistry of National Academy of Sciences of Ukraine., 1 Murmanska St., Kyiv, 02660, Ukraine
| | - V M Voitsitskiy
- National University of Life and Environmental Sciences of Ukraine, 15 Heroyiv Oborony St., Kyiv, 03041, Ukraine
| | - S V Khyzhnyak
- National University of Life and Environmental Sciences of Ukraine, 15 Heroyiv Oborony St., Kyiv, 03041, Ukraine
| | - O G Zubrikova-Chugainova
- Public institution Institute of Heart of the Ministry of Health of Ukraine, 5A Bratyslavska St., Kyiv, 02660, Ukraine
| | - V A Gorobetz
- Public institution Institute of Heart of the Ministry of Health of Ukraine, 5A Bratyslavska St., Kyiv, 02660, Ukraine
| |
Collapse
|
45
|
Matsui R, Ohtani M, Yamada K, Hikima T, Takata M, Nakamura T, Koshino H, Ishida Y, Aida T. Chemically Locked Bicelles with High Thermal and Kinetic Stability. Angew Chem Int Ed Engl 2015; 54:13284-8. [PMID: 26373898 DOI: 10.1002/anie.201506781] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Indexed: 11/08/2022]
Abstract
In situ polymerization of a bicellar mixture composed of a phospholipid and polymerizable surfactants afforded unprecedented stable bicelles. The polymerized composite showed an aligned phase over a wide thermal range (25 to >90 °C) with excellent (2)H quadrupole splitting of the solvent signal, thus implying versatility as an alignment medium for NMR studies. Crosslinking of the surfactants also brought favorable effects on the kinetic stability and alignment morphology of the bicelles. This system could thus offer a new class of scaffolds for biomembrane models.
Collapse
Affiliation(s)
- Ryoichi Matsui
- Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)
| | - Masataka Ohtani
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)
| | - Kuniyo Yamada
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)
| | - Takaaki Hikima
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)
| | - Masaki Takata
- RIKEN SPring-8 Center, 1-1-1 Kouto, Sayo, Hyogo 679-5148 (Japan)
| | - Takashi Nakamura
- RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)
| | - Hiroyuki Koshino
- RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan)
| | - Yasuhiro Ishida
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan).
| | - Takuzo Aida
- RIKEN Center for Emergent Material Science, 2-1 Hirosawa, Wako, Saitama 351-0198 (Japan).,Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)
| |
Collapse
|
46
|
Raaijmakers MJT, Schmidt T, Barth M, Tutus M, Benes NE, Wessling M. Enzymatically active ultrathin pepsin membranes. Angew Chem Int Ed Engl 2015; 54:5910-4. [PMID: 25779668 DOI: 10.1002/anie.201411263] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 01/06/2015] [Indexed: 01/10/2023]
Abstract
Enzymatically active proteins enable efficient and specific cleavage reactions of peptide bonds. Covalent coupling of the enzymes permits immobilization, which in turn reduces autolysis-induced deactivation. Ultrathin pepsin membranes were prepared by facile interfacial polycondensation of pepsin and trimesoyl chloride. The pepsin membrane allows for simultaneous enzymatic conversion and selective removal of digestion products. The large water fluxes through the membrane expedite the transport of large molecules through the pepsin layers. The presented method enables the large-scale production of ultrathin, cross-linked, enzymatically active membranes.
Collapse
Affiliation(s)
- Michiel J T Raaijmakers
- Inorganic Membranes, University of Twente, Faculty of Science and Technology, MESA+ Institute for Nanotechnology, P.O. Box 217, 7500 AE Enschede (The Netherlands)
| | | | | | | | | | | |
Collapse
|
47
|
Smith AN, Caporini MA, Fanucci GE, Long JR. A method for dynamic nuclear polarization enhancement of membrane proteins. Angew Chem Int Ed Engl 2014; 54:1542-6. [PMID: 25504310 DOI: 10.1002/anie.201410249] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Indexed: 12/29/2022]
Abstract
Dynamic nuclear polarization (DNP) magic-angle spinning (MAS) solid-state NMR (ssNMR) spectroscopy has the potential to enhance NMR signals by orders of magnitude and to enable NMR characterization of proteins which are inherently dilute, such as membrane proteins. In this work spin-labeled lipid molecules (SL-lipids), when used as polarizing agents, lead to large and relatively homogeneous DNP enhancements throughout the lipid bilayer and to an embedded lung surfactant mimetic peptide, KL4 . Specifically, DNP MAS ssNMR experiments at 600 MHz/395 GHz on KL4 reconstituted in liposomes containing SL-lipids reveal DNP enhancement values over two times larger for KL4 compared to liposome suspensions containing the biradical TOTAPOL. These findings suggest an alternative sample preparation strategy for DNP MAS ssNMR studies of lipid membranes and integral membrane proteins.
Collapse
Affiliation(s)
- Adam N Smith
- Department of Chemistry, University of Florida, 214 Leigh Hall Gainesville, FL 32611-7200 (USA)
| | | | | | | |
Collapse
|
48
|
Priegue JM, Montenegro J, Granja JR. Single-nucleotide-resolution DNA differentiation by pattern generation in lipid bilayer membranes. Small 2014; 10:3613-3618. [PMID: 24840396 DOI: 10.1002/smll.201400684] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 04/25/2014] [Indexed: 06/03/2023]
Abstract
Pattern generation/recognition in lipid bilayers is introduced for the differentiation of anionic biological relevant polymers. The amplification of the polymer differences during transport events allows the straightforward identification of a wide range collection of anionic polymers. The introduced approach displays excellent resolution even for single mutations in short single-stranded oligonuclotides.
Collapse
Affiliation(s)
- Juan M Priegue
- Singular research centre in chemical biology and molecular materials (CIQUS) and Organic Chemistry Department, University of Santiago de Compostela (USC), E-15782, Santiago de Compostela, Spain
| | | | | |
Collapse
|
49
|
Vyas KS, Vasconez HC. Wound Healing: Biologics, Skin Substitutes, Biomembranes and Scaffolds. Healthcare (Basel) 2014; 2:356-400. [PMID: 27429283 PMCID: PMC4934597 DOI: 10.3390/healthcare2030356] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/08/2014] [Accepted: 08/19/2014] [Indexed: 12/25/2022] Open
Abstract
This review will explore the latest advancements spanning several facets of wound healing, including biologics, skin substitutes, biomembranes and scaffolds.
Collapse
Affiliation(s)
- Krishna S Vyas
- Division of Plastic Surgery, Department of Surgery, University of Kentucky, Kentucky Clinic K454, 740 South Limestone, Lexington, KY 40536, USA.
| | - Henry C Vasconez
- Division of Plastic Surgery, Department of Surgery, University of Kentucky, Kentucky Clinic K454, 740 South Limestone, Lexington, KY 40536, USA.
| |
Collapse
|
50
|
Troeira Henriques S, Huang YH, Chaousis S, Wang CK, Craik DJ. Anticancer and toxic properties of cyclotides are dependent on phosphatidylethanolamine phospholipid targeting. Chembiochem 2014; 15:1956-65. [PMID: 25099014 DOI: 10.1002/cbic.201402144] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Indexed: 11/11/2022]
Abstract
Cyclotides, ultrastable disulfide-rich cyclic peptides, can be engineered to bind and inhibit specific cancer targets. In addition, some cyclotides are toxic to cancer cells, though not much is known about their mechanisms of action. Here we delineated the potential mode of action of cyclotides towards cancer cells. A novel set of analogues of kalata B1 (the prototypic cyclotide) and kalata B2 and cycloviolacin O2 were examined for their membrane-binding affinity and selectivity towards cancer cells. By using solution-state NMR, surface plasmon resonance, flow cytometry and bioassays we show that cyclotides are toxic against cancer and non-cancerous cells and their toxicity correlates with their ability to target and disrupt lipid bilayers that contain phosphatidylethanolamine phospholipids. Our results suggest that the potential of cyclotides as anticancer therapeutics might best be realised by combining their amenability to epitope engineering with their ability to bind cancer cell membranes.
Collapse
Affiliation(s)
- Sónia Troeira Henriques
- The University of Queensland, Institute for Molecular Bioscience, Carmody Road, St. Lucia, Brisbane, QLD 4072 (Australia).
| | | | | | | | | |
Collapse
|