1
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Kodedová M, Valachovič M, Sychrová H. The replacement of ergosterol with alternative sterols affects the physiological function of the yeast plasma membrane, including its H +-ATPase activity and resistance to antifungal drugs. Microbes Infect 2024:105409. [PMID: 39187062 DOI: 10.1016/j.micinf.2024.105409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Revised: 08/09/2024] [Accepted: 08/20/2024] [Indexed: 08/28/2024]
Abstract
Sterols perform essential structural and signalling functions in living organisms. Ergosterol contributes to the fluidity, permeability, microdomain formation and functionality of proteins in the yeast membrane. In our study, desmosterol was the most successful at compensating for the lack of ergosterol in Saccharomyces cerevisiae, besides stigmasterol and sitosterol. These three sterols supported cell growth without causing severe morphological defects, unlike cholesterol, 7-dehydrocholesterol, lathosterol, cholestanol or lanosterol. Together with ergosterol, they were also able to bring the plasma membrane potential of hem1Δ cells closer to the level of the wild type. In addition, desmosterol conferred even higher thermotolerance to yeast than ergosterol. Some sterols counteracted the antifungal toxicity of polyenes, azoles and terbinafine to hem1Δ cells. Plant sterols (stigmasterol, sitosterol) and desmosterol ensured the glucose-induced activation of H+-ATPase in hem1Δ cells analogously to ergosterol, whereas cholesterol and 7-dehydrocholesterol were less effective. Exogenous ergosterol, stigmasterol, sitosterol, desmosterol and cholesterol also improved the growth of Candida glabrata and Candida albicans in the presence of inhibitory concentration of fluconazole. The proper incorporation of exogenous sterols into the membrane with minimal adverse side effects on membrane functions was mainly influenced by the structure of the sterol acyl chain, and less by their ring structures.
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Affiliation(s)
- Marie Kodedová
- Laboratory of Membrane Transport, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, 142 00 Prague 4, Czech Republic.
| | - Martin Valachovič
- Department of Membrane Biochemistry, Institute of Animal Biochemistry and Genetics, Centre of Biosciences of the Slovak Academy of Sciences, Dúbravská cesta 9, 840 05 Bratislava, Slovakia.
| | - Hana Sychrová
- Laboratory of Membrane Transport, Institute of Physiology of the Czech Academy of Sciences, Vídeňská 1083, 142 00 Prague 4, Czech Republic.
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2
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Hammoudi Halat D, Younes S, Mourad N, Rahal M. Allylamines, Benzylamines, and Fungal Cell Permeability: A Review of Mechanistic Effects and Usefulness against Fungal Pathogens. MEMBRANES 2022; 12:membranes12121171. [PMID: 36557078 PMCID: PMC9781035 DOI: 10.3390/membranes12121171] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 11/14/2022] [Accepted: 11/16/2022] [Indexed: 05/30/2023]
Abstract
Allylamines, naftifine and terbinafine, and the benzylamine, butenafine, are antifungal agents with activity on the fungal cell membrane. These synthetic compounds specifically inhibit squalene epoxidase, a key enzyme in fungal sterol biosynthesis. This results in a deficiency in ergosterol, a major fungal membrane sterol that regulates membrane fluidity, biogenesis, and functions, and whose damage results in increased membrane permeability and leakage of cellular components, ultimately leading to fungal cell death. With the fungal cell membrane being predominantly made up of lipids including sterols, these lipids have a vital role in the pathogenesis of fungal infections and the identification of improved therapies. This review will focus on the fungal cell membrane structure, activity of allylamines and benzylamines, and the mechanistic damage they cause to the membrane. Furthermore, pharmaceutical preparations and clinical uses of these drugs, mainly in dermatophyte infections, will be reviewed.
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Affiliation(s)
- Dalal Hammoudi Halat
- Department of Pharmaceutical Sciences, School of Pharmacy, Lebanese International University, Bekaa 146404, Lebanon
| | - Samar Younes
- Department of Biomedical Sciences, School of Pharmacy, Lebanese International University, Bekaa 146404, Lebanon
| | - Nisreen Mourad
- Department of Pharmaceutical Sciences, School of Pharmacy, Lebanese International University, Bekaa 146404, Lebanon
| | - Mohamad Rahal
- Department of Pharmaceutical Sciences, School of Pharmacy, Lebanese International University, Bekaa 146404, Lebanon
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3
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Brauer EK, Ahsan N, Popescu GV, Thelen JJ, Popescu SC. Back From the Dead: The Atypical Kinase Activity of a Pseudokinase Regulator of Cation Fluxes During Inducible Immunity. FRONTIERS IN PLANT SCIENCE 2022; 13:931324. [PMID: 36035673 PMCID: PMC9403797 DOI: 10.3389/fpls.2022.931324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 05/27/2022] [Indexed: 06/15/2023]
Abstract
Pseudokinases are thought to lack phosphotransfer activity due to altered canonical catalytic residues within their kinase domain. However, a subset of pseudokinases maintain activity through atypical phosphotransfer mechanisms. The Arabidopsis ILK1 is a pseudokinase from the Raf-like MAP3K family and is the only known plant pseudokinase with confirmed protein kinase activity. ILK1 activity promotes disease resistance and molecular pattern-induced root growth inhibition through its stabilization of the HAK5 potassium transporter with the calmodulin-like protein CML9. ILK1 also has a kinase-independent function in salt stress suggesting that it interacts with additional proteins. We determined that members of the ILK subfamily are the sole pseudokinases within the Raf-like MAP3K family and identified 179 novel putative ILK1 protein interactors. We also identified 70 novel peptide targets for ILK1, the majority of which were phosphorylated in the presence of Mn2+ instead of Mg2+ in line with modifications in ILK1's DFG cofactor binding domain. Overall, the ILK1-targeted or interacting proteins included diverse protein types including transporters (HAK5, STP1), protein kinases (MEKK1, MEKK3), and a cytokinin receptor (AHK2). The expression of 31 genes encoding putative ILK1-interacting or phosphorylated proteins, including AHK2, were altered in the root and shoot in response to molecular patterns suggesting a role for these genes in immunity. We describe a potential role for ILK1 interactors in the context of cation-dependent immune signaling, highlighting the importance of K+ in MAMP responses. This work further supports the notion that ILK1 is an atypical kinase with an unusual cofactor dependence that may interact with multiple proteins in the cell.
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Affiliation(s)
- Elizabeth K. Brauer
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
- Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY, United States
| | - Nagib Ahsan
- Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - George V. Popescu
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
| | - Jay J. Thelen
- Department of Biochemistry, Christopher S. Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Sorina C. Popescu
- Boyce Thompson Institute for Plant Research, Ithaca, NY, United States
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4
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Zhao P, Zhao C, Chen D, Yun C, Li H, Bai L. Structure and activation mechanism of the hexameric plasma membrane H +-ATPase. Nat Commun 2021; 12:6439. [PMID: 34750373 PMCID: PMC8575881 DOI: 10.1038/s41467-021-26782-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 10/22/2021] [Indexed: 11/29/2022] Open
Abstract
The S. cerevisiae plasma membrane H+-ATPase, Pma1, is a P3A-type ATPase and the primary protein component of the membrane compartment of Pma1 (MCP). Like other plasma membrane H+-ATPases, Pma1 assembles and functions as a hexamer, a property unique to this subfamily among the larger family of P-type ATPases. It has been unclear how Pma1 organizes the yeast membrane into MCP microdomains, or why it is that Pma1 needs to assemble into a hexamer to establish the membrane electrochemical proton gradient. Here we report a high-resolution cryo-EM study of native Pma1 hexamers embedded in endogenous lipids. Remarkably, we found that the Pma1 hexamer encircles a liquid-crystalline membrane domain composed of 57 ordered lipid molecules. The Pma1-encircled lipid patch structure likely serves as the building block of the MCP. At pH 7.4, the carboxyl-terminal regulatory α-helix binds to the phosphorylation domains of two neighboring Pma1 subunits, locking the hexamer in the autoinhibited state. The regulatory helix becomes disordered at lower pH, leading to activation of the Pma1 hexamer. The activation process is accompanied by a 6.7 Å downward shift and a 40° rotation of transmembrane helices 1 and 2 that line the proton translocation path. The conformational changes have enabled us to propose a detailed mechanism for ATP-hydrolysis-driven proton pumping across the plasma membrane. Our structures will facilitate the development of antifungal drugs that target this essential protein.
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Affiliation(s)
- Peng Zhao
- Department of Biochemistry and Biophysics, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Chaoran Zhao
- Department of Biochemistry and Biophysics, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Dandan Chen
- Department of Biochemistry and Biophysics, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Caihong Yun
- Department of Biochemistry and Biophysics, School of Basic Medical Sciences, Peking University, Beijing, China
| | - Huilin Li
- Department of Structural Biology, Van Andel Institute, Grand Rapids, MI, USA.
| | - Lin Bai
- Department of Biochemistry and Biophysics, School of Basic Medical Sciences, Peking University, Beijing, China.
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5
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Santos FC, Marquês JT, Bento‐Oliveira A, Almeida RF. Sphingolipid‐enriched domains in fungi. FEBS Lett 2020; 594:3698-3718. [DOI: 10.1002/1873-3468.13986] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/21/2020] [Accepted: 10/13/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Filipa C. Santos
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
| | - Joaquim T. Marquês
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
| | - Andreia Bento‐Oliveira
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
| | - Rodrigo F.M. Almeida
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
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Plasma Membrane Protein Nce102 Modulates Morphology and Function of the Yeast Vacuole. Biomolecules 2020; 10:biom10111476. [PMID: 33114062 PMCID: PMC7690685 DOI: 10.3390/biom10111476] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/15/2020] [Accepted: 10/21/2020] [Indexed: 01/02/2023] Open
Abstract
Membrane proteins are targeted not only to specific membranes in the cell architecture, but also to distinct lateral microdomains within individual membranes to properly execute their biological functions. Yeast tetraspan protein Nce102 has been shown to migrate between such microdomains within the plasma membrane in response to an acute drop in sphingolipid levels. Combining microscopy and biochemistry methods, we show that upon gradual ageing of a yeast culture, when sphingolipid demand increases, Nce102 migrates from the plasma membrane to the vacuole. Instead of being targeted for degradation it localizes to V-ATPase-poor, i.e., ergosterol-enriched, domains of the vacuolar membrane, analogous to its plasma membrane localization. We discovered that, together with its homologue Fhn1, Nce102 modulates vacuolar morphology, dynamics, and physiology. Specifically, the fusing of vacuoles, accompanying a switch of fermenting yeast culture to respiration, is retarded in the strain missing both proteins. Furthermore, the absence of either causes an enlargement of ergosterol-rich vacuolar membrane domains, while the vacuoles themselves become smaller. Our results clearly show decreased stability of the V-ATPase in the absence of either Nce102 or Fhn1, a possible result of the disruption of normal microdomain morphology of the vacuolar membrane. Therefore, the functionality of the vacuole as a whole might be compromised in these cells.
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7
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Kodedová M, Valachovič M, Csáky Z, Sychrová H. Variations in yeast plasma‐membrane lipid composition affect killing activity of three families of insect antifungal peptides. Cell Microbiol 2019; 21:e13093. [DOI: 10.1111/cmi.13093] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 07/25/2019] [Accepted: 07/29/2019] [Indexed: 12/16/2022]
Affiliation(s)
- Marie Kodedová
- Department of Membrane Transport, Division BIOCEVInstitute of Physiology of the Czech Academy of Sciences Prague Czech Republic
| | - Martin Valachovič
- Department of Membrane Biochemistry, Institute of Animal Biochemistry and GeneticsCentre of Biosciences of the Slovak Academy of Sciences Bratislava Slovakia
| | - Zsófia Csáky
- Department of Membrane Biochemistry, Institute of Animal Biochemistry and GeneticsCentre of Biosciences of the Slovak Academy of Sciences Bratislava Slovakia
| | - Hana Sychrová
- Department of Membrane Transport, Division BIOCEVInstitute of Physiology of the Czech Academy of Sciences Prague Czech Republic
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8
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Zahumensky J, Malinsky J. Role of MCC/Eisosome in Fungal Lipid Homeostasis. Biomolecules 2019; 9:E305. [PMID: 31349700 PMCID: PMC6723945 DOI: 10.3390/biom9080305] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 12/11/2022] Open
Abstract
One of the best characterized fungal membrane microdomains is the MCC/eisosome. The MCC (membrane compartment of Can1) is an evolutionarily conserved ergosterol-rich plasma membrane domain. It is stabilized on its cytosolic face by the eisosome, a hemitubular protein complex composed of Bin/Amphiphysin/Rvs (BAR) domain-containing Pil1 and Lsp1. These two proteins bind directly to phosphatidylinositol 4,5-bisphosphate and promote the typical furrow-like shape of the microdomain, with highly curved edges and bottom. While some proteins display stable localization in the MCC/eisosome, others enter or leave it under particular conditions, such as misbalance in membrane lipid composition, changes in membrane tension, or availability of specific nutrients. These findings reveal that the MCC/eisosome, a plasma membrane microdomain with distinct morphology and lipid composition, acts as a multifaceted regulator of various cellular processes including metabolic pathways, cellular morphogenesis, signalling cascades, and mRNA decay. In this minireview, we focus on the MCC/eisosome's proposed role in the regulation of lipid metabolism. While the molecular mechanisms of the MCC/eisosome function are not completely understood, the idea of intracellular processes being regulated at the plasma membrane, the foremost barrier exposed to environmental challenges, is truly exciting.
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Affiliation(s)
- Jakub Zahumensky
- Department of Microscopy, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic
| | - Jan Malinsky
- Department of Microscopy, Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic.
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9
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Busto JV, Wedlich-Söldner R. Integration Through Separation - The Role of Lateral Membrane Segregation in Nutrient Uptake. Front Cell Dev Biol 2019; 7:97. [PMID: 31294021 PMCID: PMC6603244 DOI: 10.3389/fcell.2019.00097] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 05/21/2019] [Indexed: 12/12/2022] Open
Abstract
Nutrient transporters are prominent and ubiquitous components of the plasma membrane in all cell types. Their expression and regulation are tightly linked to the cells’ needs. Environmental factors such as nutrient starvation or osmotic stress prompt an acute remodeling of transporters and the plasma membrane to efficiently maintain homeostasis in cell metabolism. Lateral confinement of nutrient transporters through dynamic segregation within the plasma membrane has recently emerged as an important phenomenon that facilitates spatiotemporal control of nutrient uptake and metabolic regulation. Here, we review recent studies highlighting the mechanisms connecting the function of amino acid permeases with their endocytic turnover and lateral segregation within the plasma membrane. These findings indicate that actively controlled lateral compartmentalization of plasma membrane components constitutes an important level of regulation during acute cellular adaptations.
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Affiliation(s)
- Jon V Busto
- Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany.,Biofisika Institute (CSIC, UPV/EHU) and Department of Biochemistry, University of the Basque Country, Leioa, Spain
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10
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Klimanova EA, Sidorenko SV, Smolyaninova LV, Kapilevich LV, Gusakova SV, Lopina OD, Orlov SN. Ubiquitous and cell type-specific transcriptomic changes triggered by dissipation of monovalent cation gradients in rodent cells: Physiological and pathophysiological implications. CURRENT TOPICS IN MEMBRANES 2019; 83:107-149. [PMID: 31196602 DOI: 10.1016/bs.ctm.2019.01.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Elevation of [Na+]i/[K+]i-ratio is considered as one of the major signals triggering transcriptomic changes in various cells types. In this study, we identified ubiquitous and cell type-specific [Formula: see text] -sensitive genes by comparative analysis of transcriptomic changes in ouabain-treated rat aorta smooth muscle cells and rat aorta endothelial cells (RASMC and RAEC, respectively), rat cerebellar granule cells (RCGC), and mouse C2C12 myoblasts. Exposure of the cells to ouabain increased intracellular Na+ content by ~14, 8, 7, and 6-fold and resulted in appearance of 7577, 2698, 2120, and 1146 differentially expressed transcripts in RAEC, RASMC, C2C12, and RCGC, respectively. Eighty-three genes were found as the intersection of the four sets of identified transcripts corresponding to each cell type and are classified as ubiquitous. Among the 10 top upregulated ubiquitous transcripts are the following: Dusp6, Plk3, Trib1, Ccl7, Mafk, Atf3, Ptgs2, Cxcl1, Spry4, and Coq10b. Unique transcripts whose expression is cell-specific include 4897, 1523, 789, and 494 transcripts for RAEC, RASMC, C2C12, and RCGC, respectively. The role of gene expression and signal pathways induced by dissipation of transmembrane gradient of monovalent cations in the development of various diseases is discussed with special attention to cardiovascular and pulmonary illnesses.
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Affiliation(s)
- Elizaveta A Klimanova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia.
| | - Svetlana V Sidorenko
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia
| | - Larisa V Smolyaninova
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia
| | | | | | - Olga D Lopina
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Sergei N Orlov
- Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia; National Research Tomsk State University, Tomsk, Russia; Siberian State Medical University, Tomsk, Russia
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11
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Baluška F, Mancuso S. Actin Cytoskeleton and Action Potentials: Forgotten Connections. THE CYTOSKELETON 2019. [DOI: 10.1007/978-3-030-33528-1_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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12
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Daptomycin Pore Formation and Stoichiometry Depend on Membrane Potential of Target Membrane. Antimicrob Agents Chemother 2018; 63:AAC.01589-18. [PMID: 30323037 DOI: 10.1128/aac.01589-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/06/2018] [Indexed: 12/14/2022] Open
Abstract
Daptomycin is a calcium-dependent lipodepsipeptide antibiotic clinically used to treat serious infections caused by Gram-positive pathogens. Its precise mode of action is somewhat controversial; the biggest issue is daptomycin pore formation, which we directly investigated here. We first performed a screening experiment using propidium iodide (PI) entry to Bacillus subtilis cells and chose the optimum and therapeutically relevant conditions (10 µg/ml daptomycin and 1.25 mM CaCl2) for the subsequent analyses. Using conductance measurements on planar lipid bilayers, we show that daptomycin forms nonuniform oligomeric pores with conductance ranging from 120 pS to 14 nS. The smallest conductance unit is probably a dimer; however, tetramers and pentamers occur in the membrane most frequently. Moreover, daptomycin pore-forming activity is exponentially dependent on the applied membrane voltage. We further analyzed the membrane-permeabilizing activity in B. subtilis cells using fluorescence methods [PI and DiSC3(5)]. Daptomycin most rapidly permeabilizes cells with high initial membrane potential and dissipates it within a few minutes. Low initial membrane potential hinders daptomycin pore formation.
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13
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Lin X, Nair V, Zhou Y, Gorfe AA. Membrane potential and dynamics in a ternary lipid mixture: insights from molecular dynamics simulations. Phys Chem Chem Phys 2018; 20:15841-15851. [PMID: 29845130 DOI: 10.1039/c8cp01629a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Transmembrane potential (Vm) plays critical roles in cell signaling and other functions. However, the impact of Vm on the structure and dynamics of membrane lipids and proteins, which are critical for the regulation of signaling, is still an open question. All-atom molecular dynamics (MD) simulation is emerging as a useful technique to address this issue. Previous atomistic MD simulations of pure or binary model membranes indicated that both ion imbalance and electric field can be used to generate Vm, but both approaches failed to yield structural changes in lipids with statistical significance. We hypothesized that a possible reason for this could be oversimplified membrane composition or limited sampling. In this work, we tested if and how Vm modulates the structure and dynamics of lipids in a physiologically relevant model membrane. Using a detailed side-by-side comparison, we first show that while both ion imbalance and electric field generate Vm in our complex membranes, only the latter could produce physiologically relevant Vm. We further show that double bonds in lipid acyl chains have a relatively large sensitivity to Vm. A single-bilayer model with an electric field showed the highest sensitivity in simulations under the isothermal-isobaric (NPT) ensemble, reproducing expected responses of head-group dipoles to Vm and suggesting that this approach may be more suitable for studying the structural effects of Vm. Our findings also shed light on the relationship between the macroscopic Vm and its atomic-level underpinnings.
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Affiliation(s)
- Xubo Lin
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center at Houston, Texas 77030, USA
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14
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Marquês JT, Marinho HS, de Almeida RF. Sphingolipid hydroxylation in mammals, yeast and plants – An integrated view. Prog Lipid Res 2018; 71:18-42. [DOI: 10.1016/j.plipres.2018.05.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/11/2018] [Accepted: 05/04/2018] [Indexed: 02/07/2023]
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15
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Bouklas T, Alonso-Crisóstomo L, Székely T, Diago-Navarro E, Orner EP, Smith K, Munshi MA, Del Poeta M, Balázsi G, Fries BC. Generational distribution of a Candida glabrata population: Resilient old cells prevail, while younger cells dominate in the vulnerable host. PLoS Pathog 2017; 13:e1006355. [PMID: 28489916 PMCID: PMC5440053 DOI: 10.1371/journal.ppat.1006355] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 05/22/2017] [Accepted: 04/15/2017] [Indexed: 12/15/2022] Open
Abstract
Similar to other yeasts, the human pathogen Candida glabrata ages when it undergoes asymmetric, finite cell divisions, which determines its replicative lifespan. We sought to investigate if and how aging changes resilience of C. glabrata populations in the host environment. Our data demonstrate that old C. glabrata are more resistant to hydrogen peroxide and neutrophil killing, whereas young cells adhere better to epithelial cell layers. Consequently, virulence of old compared to younger C. glabrata cells is enhanced in the Galleria mellonella infection model. Electron microscopy images of old C. glabrata cells indicate a marked increase in cell wall thickness. Comparison of transcriptomes of old and young C. glabrata cells reveals differential regulation of ergosterol and Hog pathway associated genes as well as adhesion proteins, and suggests that aging is accompanied by remodeling of the fungal cell wall. Biochemical analysis supports this conclusion as older cells exhibit a qualitatively different lipid composition, leading to the observed increased emergence of fluconazole resistance when grown in the presence of fluconazole selection pressure. Older C. glabrata cells accumulate during murine and human infection, which is statistically unlikely without very strong selection. Therefore, we tested the hypothesis that neutrophils constitute the predominant selection pressure in vivo. When we altered experimentally the selection pressure by antibody-mediated removal of neutrophils, we observed a significantly younger pathogen population in mice. Mathematical modeling confirmed that differential selection of older cells is sufficient to cause the observed demographic shift in the fungal population. Hence our data support the concept that pathogenesis is affected by the generational age distribution of the infecting C. glabrata population in a host. We conclude that replicative aging constitutes an emerging trait, which is selected by the host and may even play an unanticipated role in the transition from a commensal to a pathogen state.
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Affiliation(s)
- Tejas Bouklas
- Department of Medicine, Division of Infectious Diseases, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biomedical Sciences, Long Island University-Post, Brookville, New York, United States of America
| | | | - Tamás Székely
- The Louis and Beatrice Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Elizabeth Diago-Navarro
- Department of Medicine, Division of Infectious Diseases, Stony Brook University, Stony Brook, New York, United States of America
| | - Erika P. Orner
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Kalie Smith
- Department of Medicine, Division of Infectious Diseases, Stony Brook University, Stony Brook, New York, United States of America
| | - Mansa A. Munshi
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
- Veterans Administration Medical Center, Northport, New York, United States of America
| | - Gábor Balázsi
- The Louis and Beatrice Laufer Center for Physical and Quantitative Biology, Stony Brook University, Stony Brook, New York, United States of America
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, New York, United States of America
| | - Bettina C. Fries
- Department of Medicine, Division of Infectious Diseases, Stony Brook University, Stony Brook, New York, United States of America
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, United States of America
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16
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Urrego D, Sánchez A, Tomczak AP, Pardo LA. The electric fence to cell-cycle progression: Do local changes in membrane potential facilitate disassembly of the primary cilium? Bioessays 2017; 39. [DOI: 10.1002/bies.201600190] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Diana Urrego
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
| | - Araceli Sánchez
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
| | - Adam P. Tomczak
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
| | - Luis A. Pardo
- Max-Planck-Institut für experimentelle Medizin; AG Oncophysiology; Göttingen Germany
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Bernardino de la Serna J, Schütz GJ, Eggeling C, Cebecauer M. There Is No Simple Model of the Plasma Membrane Organization. Front Cell Dev Biol 2016; 4:106. [PMID: 27747212 PMCID: PMC5040727 DOI: 10.3389/fcell.2016.00106] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 09/14/2016] [Indexed: 12/29/2022] Open
Abstract
Ever since technologies enabled the characterization of eukaryotic plasma membranes, heterogeneities in the distributions of its constituents were observed. Over the years this led to the proposal of various models describing the plasma membrane organization such as lipid shells, picket-and-fences, lipid rafts, or protein islands, as addressed in numerous publications and reviews. Instead of emphasizing on one model we in this review give a brief overview over current models and highlight how current experimental work in one or the other way do not support the existence of a single overarching model. Instead, we highlight the vast variety of membrane properties and components, their influences and impacts. We believe that highlighting such controversial discoveries will stimulate unbiased research on plasma membrane organization and functionality, leading to a better understanding of this essential cellular structure.
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Affiliation(s)
- Jorge Bernardino de la Serna
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Central Laser Facility, Research Complex at Harwell Harwell, UK
| | - Gerhard J Schütz
- Institute of Applied Physics, Technische Universität Wien Wien, Austria
| | - Christian Eggeling
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford Headley Way, UK
| | - Marek Cebecauer
- Department of Biophysical Chemistry, J.Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences Prague, Czech Republic
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New Insight Into the Roles of Membrane Microdomains in Physiological Activities of Fungal Cells. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 325:119-80. [PMID: 27241220 DOI: 10.1016/bs.ircmb.2016.02.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The organization of biological membranes into structurally and functionally distinct lateral microdomains is generally accepted. From bacteria to mammals, laterally compartmentalized membranes seem to be a vital attribute of life. The crucial fraction of our current knowledge about the membrane microdomains has been gained from studies on fungi. In this review we summarize the evidence of the microdomain organization of membranes from fungal cells, with accent on their enormous diversity in composition, temporal dynamics, modes of formation, and recognized engagement in the cell physiology. A special emphasis is laid on the fact that in addition to their other biological functions, membrane microdomains also mediate the communication among different membranes within a eukaryotic cell and coordinate their functions. Involvement of fungal membrane microdomains in stress sensing, regulation of lipid homeostasis, and cell differentiation is discussed more in detail.
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