224 results on '"Yuri N. Antonenko"'
Search Results
2. Rhodamine 19 Alkyl Esters as Effective Antibacterial Agents
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Pavel A. Nazarov, Vladislav S. Maximov, Alexander M. Firsov, Marina V. Karakozova, Veronika Panfilova, Elena A. Kotova, Maxim V. Skulachev, and Yuri N. Antonenko
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MDR pumps ,AcrAB-TolC ,mitochondria-targeted antioxidants ,rhodamine ,phosphonium ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Mitochondria-targeted antioxidants (MTAs) have been studied quite intensively in recent years as potential therapeutic agents and vectors for the delivery of other active substances to mitochondria and bacteria. Their most studied representatives are MitoQ and SkQ1, with its fluorescent rhodamine analog SkQR1, a decyl ester of rhodamine 19 carrying plastoquinone. In the present work, we observed a pronounced antibacterial action of SkQR1 against Gram-positive bacteria, but virtually no effect on Gram-negative bacteria. The MDR pump AcrAB-TolC, known to expel SkQ1, did not recognize and did not pump out SkQR1 and dodecyl ester of rhodamine 19 (C12R1). Rhodamine 19 butyl (C4R1) and ethyl (C2R1) esters more effectively suppressed the growth of ΔtolC Escherichia coli, but lost their potency with the wild-type E. coli pumping them out. The mechanism of the antibacterial action of SkQR1 may differ from that of SkQ1. The rhodamine derivatives also proved to be effective antibacterial agents against various Gram-positive species, including Staphylococcus aureus and Mycobacterium smegmatis. By using fluorescence correlation spectroscopy and fluorescence microscopy, SkQR1 was shown to accumulate in the bacterial membrane. Thus, the presentation of SkQR1 as a fluorescent analogue of SkQ1 and its use for visualization should be performed with caution.
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- 2024
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3. Mirror proteorhodopsins
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Ivan S. Okhrimenko, Kirill Kovalev, Lada E. Petrovskaya, Nikolay S. Ilyinsky, Alexey A. Alekseev, Egor Marin, Tatyana I. Rokitskaya, Yuri N. Antonenko, Sergey A. Siletsky, Petr A. Popov, Yuliya A. Zagryadskaya, Dmytro V. Soloviov, Igor V. Chizhov, Dmitrii V. Zabelskii, Yury L. Ryzhykau, Alexey V. Vlasov, Alexander I. Kuklin, Andrey O. Bogorodskiy, Anatolii E. Mikhailov, Daniil V. Sidorov, Siarhei Bukhalovich, Fedor Tsybrov, Sergey Bukhdruker, Anastasiia D. Vlasova, Valentin I. Borshchevskiy, Dmitry A. Dolgikh, Mikhail P. Kirpichnikov, Ernst Bamberg, and Valentin I. Gordeliy
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Chemistry ,QD1-999 - Abstract
Abstract Proteorhodopsins (PRs), bacterial light-driven outward proton pumps comprise the first discovered and largest family of rhodopsins, they play a significant role in life on the Earth. A big remaining mystery was that up-to-date there was no described bacterial rhodopsins pumping protons at acidic pH despite the fact that bacteria live in different pH environment. Here we describe conceptually new bacterial rhodopsins which are operating as outward proton pumps at acidic pH. A comprehensive function-structure study of a representative of a new clade of proton pumping rhodopsins which we name “mirror proteorhodopsins”, from Sphingomonas paucimobilis (SpaR) shows cavity/gate architecture of the proton translocation pathway rather resembling channelrhodopsins than the known rhodopsin proton pumps. Another unique property of mirror proteorhodopsins is that proton pumping is inhibited by a millimolar concentration of zinc. We also show that mirror proteorhodopsins are extensively represented in opportunistic multidrug resistant human pathogens, plant growth-promoting and zinc solubilizing bacteria. They may be of optogenetic interest.
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- 2023
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4. Trialkyl(vinyl)phosphonium Chlorophenol Derivatives as Potent Mitochondrial Uncouplers and Antibacterial Agents
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Natalia V. Terekhova, Lyudmila S. Khailova, Tatyana I. Rokitskaya, Pavel A. Nazarov, Daut R. Islamov, Konstantin S. Usachev, Dmitry A. Tatarinov, Vladimir F. Mironov, Elena A. Kotova, and Yuri N. Antonenko
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Chemistry ,QD1-999 - Published
- 2021
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5. Mitochondrial ATP Synthase and Mild Uncoupling by Butyl Ester of Rhodamine 19, C4R1
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Ljubava D. Zorova, Irina B. Pevzner, Ljudmila S. Khailova, Galina A. Korshunova, Marina A. Kovaleva, Leonid I. Kovalev, Marina V. Serebryakova, Denis N. Silachev, Roman V. Sudakov, Savva D. Zorov, Tatyana I. Rokitskaya, Vasily A. Popkov, Egor Y. Plotnikov, Yuri N. Antonenko, and Dmitry B. Zorov
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mitochondria ,mitochondria-targeted drugs ,antioxidants ,mild uncoupling ,ATP synthase ,Complex V ,Therapeutics. Pharmacology ,RM1-950 - Abstract
The homeostasis of the transmembrane potential of hydrogen ions in mitochondria is a prerequisite for the normal mitochondrial functioning. However, in different pathological conditions it is advisable to slightly reduce the membrane potential, while maintaining it at levels sufficient to produce ATP that will ensure the normal functioning of the cell. A number of chemical agents have been found to provide mild uncoupling; however, natural proteins residing in mitochondrial membrane can carry this mission, such as proteins from the UCP family, an adenine nucleotide translocator and a dicarboxylate carrier. In this study, we demonstrated that the butyl ester of rhodamine 19, C4R1, binds to the components of the mitochondrial ATP synthase complex due to electrostatic interaction and has a good uncoupling effect. The more hydrophobic derivative C12R1 binds poorly to mitochondria with less uncoupling activity. Mass spectrometry confirmed that C4R1 binds to the β-subunit of mitochondrial ATP synthase and based on molecular docking, a C4R1 binding model was constructed suggesting the binding site on the interface between the α- and β-subunits, close to the anionic amino acid residues of the β-subunit. The association of the uncoupling effect with binding suggests that the ATP synthase complex can provide induced uncoupling.
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- 2023
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6. Usnic Acid-Mediated Exchange of Protons for Divalent Metal Cations across Lipid Membranes: Relevance to Mitochondrial Uncoupling
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Tatyana I. Rokitskaya, Alexander M. Arutyunyan, Ljudmila S. Khailova, Alisa D. Kataeva, Alexander M. Firsov, Elena A. Kotova, and Yuri N. Antonenko
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usnic acid ,bilayer lipid membrane ,mitochondrial uncoupler ,protonophore ,divalent metal cation/proton exchange ,circular dichroism ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Usnic acid (UA), a unique lichen metabolite, is a protonophoric uncoupler of oxidative phosphorylation, widely known as a weight-loss dietary supplement. In contrast to conventional proton-shuttling mitochondrial uncouplers, UA was found to carry protons across lipid membranes via the induction of an electrogenic proton exchange for calcium or magnesium cations. Here, we evaluated the ability of various divalent metal cations to stimulate a proton transport through both planar and vesicular bilayer lipid membranes by measuring the transmembrane electrical current and fluorescence-detected pH gradient dissipation in pyranine-loaded liposomes, respectively. Thus, we obtained the following selectivity series of calcium, magnesium, zinc, manganese and copper cations: Zn2+ > Mn2+ > Mg2+ > Ca2+ >> Cu2+. Remarkably, Cu2+ appeared to suppress the UA-mediated proton transport in both lipid membrane systems. The data on the divalent metal cation/proton exchange were supported by circular dichroism spectroscopy of UA in the presence of the corresponding cations.
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- 2022
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7. Pioglitazone Is a Mild Carrier-Dependent Uncoupler of Oxidative Phosphorylation and a Modulator of Mitochondrial Permeability Transition
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Ekaterina S. Kharechkina, Anna B. Nikiforova, Konstantin N. Belosludtsev, Tatyana I. Rokitskaya, Yuri N. Antonenko, and Alexey G. Kruglov
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permeability transition pore ,unilamellar vesicles ,adenine nucleotide translocase ,uncoupling protein ,ATP production ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Pioglitazone (PIO) is an insulin-sensitizing antidiabetic drug, which normalizes glucose and lipid metabolism but may provoke heart and liver failure and chronic kidney diseases. Both therapeutic and adverse effects of PIO can be accomplished through mitochondrial targets. Here, we explored the capability of PIO to modulate the mitochondrial membrane potential (ΔΨm) and the permeability transition pore (mPTP) opening in different models in vitro. ΔΨm was measured using tetraphenylphosphonium and the fluorescent dye rhodamine 123. The coupling of oxidative phosphorylation was estimated polarographically. The transport of ions and solutes across membranes was registered by potentiometric and spectral techniques. We found that PIO decreased ΔΨm in isolated mitochondria and intact thymocytes and the efficiency of ADP phosphorylation, particularly after the addition of Ca2+. The presence of the cytosolic fraction mitigated mitochondrial depolarization but made it sustained. Carboxyatractyloside diminished the PIO-dependent depolarization. PIO activated proton transport in deenergized mitochondria but not in artificial phospholipid vesicles. PIO had no effect on K+ and Ca2+ inward transport but drastically decreased the mitochondrial Ca2+-retention capacity and protective effects of adenine nucleotides against mPTP opening. Thus, PIO is a mild, partly ATP/ADP-translocase-dependent, uncoupler and a modulator of ATP production and mPTP sensitivity to Ca2+ and adenine nucleotides. These properties contribute to both therapeutic and adverse effects of PIO.
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- 2021
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8. Mitochondrial Uncoupling Proteins (UCP1-UCP3) and Adenine Nucleotide Translocase (ANT1) Enhance the Protonophoric Action of 2,4-Dinitrophenol in Mitochondria and Planar Bilayer Membranes
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Kristina Žuna, Olga Jovanović, Ljudmila S. Khailova, Sanja Škulj, Zlatko Brkljača, Jürgen Kreiter, Elena A. Kotova, Mario Vazdar, Yuri N. Antonenko, and Elena E. Pohl
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mitochondrial uncoupler ,protonophore ,membrane potential ,proton conductance ,artificial membranes ,molecular dynamics simulations ,Microbiology ,QR1-502 - Abstract
2,4-Dinitrophenol (DNP) is a classic uncoupler of oxidative phosphorylation in mitochondria which is still used in “diet pills”, despite its high toxicity and lack of antidotes. DNP increases the proton current through pure lipid membranes, similar to other chemical uncouplers. However, the molecular mechanism of its action in the mitochondria is far from being understood. The sensitivity of DNP’s uncoupling action in mitochondria to carboxyatractyloside, a specific inhibitor of adenine nucleotide translocase (ANT), suggests the involvement of ANT and probably other mitochondrial proton-transporting proteins in the DNP’s protonophoric activity. To test this hypothesis, we investigated the contribution of recombinant ANT1 and the uncoupling proteins UCP1-UCP3 to DNP-mediated proton leakage using the well-defined model of planar bilayer lipid membranes. All four proteins significantly enhanced the protonophoric effect of DNP. Notably, only long-chain free fatty acids were previously shown to be co-factors of UCPs and ANT1. Using site-directed mutagenesis and molecular dynamics simulations, we showed that arginine 79 of ANT1 is crucial for the DNP-mediated increase of membrane conductance, implying that this amino acid participates in DNP binding to ANT1.
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- 2021
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9. Triphenilphosphonium Analogs of Chloramphenicol as Dual-Acting Antimicrobial and Antiproliferating Agents
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Julia A. Pavlova, Zimfira Z. Khairullina, Andrey G. Tereshchenkov, Pavel A. Nazarov, Dmitrii A. Lukianov, Inna A. Volynkina, Dmitry A. Skvortsov, Gennady I. Makarov, Etna Abad, Somay Y. Murayama, Susumu Kajiwara, Alena Paleskava, Andrey L. Konevega, Yuri N. Antonenko, Alex Lyakhovich, Ilya A. Osterman, Alexey A. Bogdanov, and Natalia V. Sumbatyan
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chloramphenicol ,alkyl(triphenyl)phosphonium ,bacterial ribosome ,molecular dynamics simulations ,antibiotic activity ,antiproliferative activity ,Therapeutics. Pharmacology ,RM1-950 - Abstract
In the current work, in continuation of our recent research, we synthesized and studied new chimeric compounds, including the ribosome-targeting antibiotic chloramphenicol (CHL) and the membrane-penetrating cation triphenylphosphonium (TPP), which are linked by alkyl groups of different lengths. Using various biochemical assays, we showed that these CAM-Cn-TPP compounds bind to the bacterial ribosome, inhibit protein synthesis in vitro and in vivo in a way similar to that of the parent CHL, and significantly reduce membrane potential. Similar to CAM-C4-TPP, the mode of action of CAM-C10-TPP and CAM-C14-TPP in bacterial ribosomes differs from that of CHL. By simulating the dynamics of CAM-Cn-TPP complexes with bacterial ribosomes, we proposed a possible explanation for the specificity of the action of these analogs in the translation process. CAM-C10-TPP and CAM-C14-TPP more strongly inhibit the growth of the Gram-positive bacteria, as compared to CHL, and suppress some CHL-resistant bacterial strains. Thus, we have shown that TPP derivatives of CHL are dual-acting compounds targeting both the ribosomes and cellular membranes of bacteria. The TPP fragment of CAM-Cn-TPP compounds has an inhibitory effect on bacteria. Moreover, since the mitochondria of eukaryotic cells possess qualities similar to those of their prokaryotic ancestors, we demonstrate the possibility of targeting chemoresistant cancer cells with these compounds.
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- 2021
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10. Mitochondria-targeted antioxidants as highly effective antibiotics
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Pavel A. Nazarov, Ilya A. Osterman, Artem V. Tokarchuk, Marina V. Karakozova, Galina A. Korshunova, Konstantin G. Lyamzaev, Maxim V. Skulachev, Elena A. Kotova, Vladimir P. Skulachev, and Yuri N. Antonenko
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Medicine ,Science - Abstract
Abstract Mitochondria-targeted antioxidants are known to alleviate mitochondrial oxidative damage that is associated with a variety of diseases. Here, we showed that SkQ1, a decyltriphenyl phosphonium cation conjugated to a quinone moiety, exhibited strong antibacterial activity towards Gram-positive Bacillus subtilis, Mycobacterium sp. and Staphylococcus aureus and Gram-negative Photobacterium phosphoreum and Rhodobacter sphaeroides in submicromolar and micromolar concentrations. SkQ1 exhibited less antibiotic activity towards Escherichia coli due to the presence of the highly effective multidrug resistance pump AcrAB-TolC. E. coli mutants lacking AcrAB-TolC showed similar SkQ1 sensitivity, as B. subtilis. Lowering of the bacterial membrane potential by SkQ1 might be involved in the mechanism of its bactericidal action. No significant cytotoxic effect on mammalian cells was observed at bacteriotoxic concentrations of SkQ1. Therefore, SkQ1 may be effective in protection of the infected mammals by killing invading bacteria.
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- 2017
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11. Fluorescein Derivatives as Antibacterial Agents Acting via Membrane Depolarization
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Pavel A. Nazarov, Roman S. Kirsanov, Stepan S. Denisov, Ljudmila S. Khailova, Marina V. Karakozova, Konstantin G. Lyamzaev, Galina A. Korshunova, Konstantin A. Lukyanov, Elena A. Kotova, and Yuri N. Antonenko
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fluorescein derivative ,antibacterial agent ,bacterial membrane depolarization ,mitochondria ,membrane potential ,fluorescent uncoupler ,Microbiology ,QR1-502 - Abstract
Appending a lipophylic alkyl chain by ester bond to fluorescein has been previously shown to convert this popular dye into an effective protonophoric uncoupler of oxidative phosphorylation in mitochondria, exhibiting neuro- and nephroprotective effects in murine models. In line with this finding, we here report data on the pronounced depolarizing effect of a series of fluorescein decyl esters on bacterial cells. The binding of the fluorescein derivatives to Bacillus subtilis cells was monitored by fluorescence microscopy and fluorescence correlation spectroscopy (FCS). FCS revealed the energy-dependent accumulation of the fluorescein esters with decyl(triphenyl)- and decyl(tri-p-tolyl)phosphonium cations in the bacterial cells. The latter compound proved to be the most potent in suppressing B. subtilis growth.
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- 2020
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12. Membrane Binding of Neuronal Calcium Sensor-1: Highly Specific Interaction with Phosphatidylinositol-3-Phosphate
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Viktoriia E. Baksheeva, Ekaterina L. Nemashkalova, Alexander M. Firsov, Arthur O. Zalevsky, Vasily I. Vladimirov, Natalia K. Tikhomirova, Pavel P. Philippov, Andrey A. Zamyatnin, Dmitry V. Zinchenko, Yuri N. Antonenko, Sergey E. Permyakov, and Evgeni Yu. Zernii
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neuronal calcium sensors ,neuronal calcium sensor-1 ,ncs-1 ,membrane binding ,n-terminal myristoylation ,myristoyl group ,phospholipid-binding proteins ,phosphoinositides ,phosphatidylinositol-3-phosphate ,pi3p ,Microbiology ,QR1-502 - Abstract
Neuronal calcium sensors are a family of N-terminally myristoylated membrane-binding proteins possessing a different intracellular localization and thereby targeting unique signaling partner(s). Apart from the myristoyl group, the membrane attachment of these proteins may be modulated by their N-terminal positively charged residues responsible for specific recognition of the membrane components. Here, we examined the interaction of neuronal calcium sensor-1 (NCS-1) with natural membranes of different lipid composition as well as individual phospholipids in form of multilamellar liposomes or immobilized monolayers and characterized the role of myristoyl group and N-terminal lysine residues in membrane binding and phospholipid preference of the protein. NCS-1 binds to photoreceptor and hippocampal membranes in a Ca2+-independent manner and the binding is attenuated in the absence of myristoyl group. Meanwhile, the interaction with photoreceptor membranes is less dependent on myristoylation and more sensitive to replacement of K3, K7, and/or K9 of NCS-1 by glutamic acid, reflecting affinity of the protein to negatively charged phospholipids. Consistently, among the major phospholipids, NCS-1 preferentially interacts with phosphatidylserine and phosphatidylinositol with micromolar affinity and the interaction with the former is inhibited upon mutating of N-terminal lysines of the protein. Remarkably, NCS-1 demonstrates pronounced specific binding to phosphoinositides with high preference for phosphatidylinositol-3-phosphate. The binding does not depend on myristoylation and, unexpectedly, is not sensitive to the charge inversion mutations. Instead, phosphatidylinositol-3-phosphate can be recognized by a specific site located in the N-terminal region of the protein. These data provide important novel insights into the general mechanism of membrane binding of NCS-1 and its targeting to specific phospholipids ensuring involvement of the protein in phosphoinositide-regulated signaling pathways.
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- 2020
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13. Interaction of Potent Mitochondrial Uncouplers with Thiol-Containing Antioxidants
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Ljudmila S. Khailova, Alexander M. Firsov, Elena A. Kotova, and Yuri N. Antonenko
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mitochondrial uncoupler ,FCCP ,fluazinam ,membrane potential ,respiration rate ,isolated mitochondria ,reactive oxygen species ,thiol-containing antioxidants ,planar bilayer lipid membrane ,Therapeutics. Pharmacology ,RM1-950 - Abstract
It is generally considered that reactive oxygen species (ROS) are involved in the development of numerous pathologies. The level of ROS can be altered via the uncoupling of oxidative phosphorylation by using protonophores causing mitochondrial membrane depolarization. Here, we report that the uncoupling activity of potent protonophores, such as carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone (FCCP), carbonyl cyanide 3-chlorophenylhydrazone (CCCP), and fluazinam, can be abrogated by the addition of thiol-containing antioxidants to isolated mitochondria. In particular, N-acetylcysteine, glutathione, cysteine, and dithiothreitol removed both a decrease in the mitochondrial membrane potential and an increase in the respiration rate that is caused by FCCP. The thiols also reduced the electrical current that is induced by FCCP and CCCP across planar bilayer lipid membranes. Thus, when speculating on the mechanistic roles of ROS level modulation by mitochondrial uncoupling based on the antioxidant reversing certain FCCP and CCCP effects on cellular processes, one should take into account the ability of these protonophoric uncouplers to directly interact with the thiol-containing antioxidants.
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- 2019
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14. Synchronization of opening and closing of two gramicidin A channels pulled together by a linker: possible relevance to channel clustering
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Vladimir I. Novoderezhkin, Tatyana I. Rokitskaya, Elena A. Kotova, and Yuri N. Antonenko
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General Physics and Astronomy ,Physical and Theoretical Chemistry - Abstract
Here, we used the ideas of the theory of excitons to hypothesize about the mechanism of synchronous opening and closing of two membrane channels formed by laterally linked gramicidin A subunits.
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- 2023
15. Antibiotic Pyrrolomycin as an Efficient Mitochondrial Uncoupler
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Alexander M. Firsov, Ljudmila S. Khailova, Tatyana I. Rokitskaya, Elena A. Kotova, and Yuri N. Antonenko
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Uncoupling Agents ,Lipid Bilayers ,Biophysics ,Mitochondria, Liver ,General Medicine ,Biochemistry ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Anti-Bacterial Agents ,Mitochondria ,Rats ,Phloretin ,Liposomes ,Animals ,Geriatrics and Gerontology - Abstract
Pyrrolomycins C (Pyr_C) and D (Pyr_D) are antibiotics produced by Actinosporangium and Streptomyces. The mechanism of their antimicrobial activity consists in depolarization of bacterial membrane, leading to the suppression of bacterial bioenergetics through the uncoupling of oxidative phosphorylation, which is based on the protonophore action of these antibiotics [Valderrama et al., Antimicrob. Agents Chemother. (2019) 63, e01450]. Here, we studied the effect of pyrrolomycins on the isolated rat liver mitochondria. Pyr_C was found to be more active than Pyr_D and uncoupled mitochondria in the submicromolar concentration range, which was observed as the mitochondrial membrane depolarization and stimulation of mitochondrial respiration. In the case of mitoplasts (isolated mitochondria with impaired outer membrane integrity), the difference in the action of Pyr_C and Pyr_D was significantly less pronounced. By contrast, in inverted submitochondrial particles (SMPs), Pyr_D was more active as an uncoupler, which caused collapse of the membrane potential even at the nanomolar concentrations. The same ratio of the protonophoric activity of Pyr_D and Pyr_C was obtained by us on liposomes loaded with the pH indicator pyranine. The protonophore activity of Pyr_D in the planar bilayer lipid membranes (BLMs) was maximal at ~pH 9, i.e., at pH values close to pK
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- 2022
16. Membrane Permeability of Modified Butyltriphenylphosphonium Cations
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Tatyana I. Rokitskaya, Ekaterina V. Aleksandrova, Galina A. Korshunova, Ljudmila S. Khailova, Vadim N. Tashlitsky, Victor B. Luzhkov, and Yuri N. Antonenko
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Onium Compounds ,Organophosphorus Compounds ,Cations ,Lipid Bilayers ,Materials Chemistry ,Animals ,Physical and Theoretical Chemistry ,Permeability ,Rats ,Surfaces, Coatings and Films - Abstract
The alkyltriphenylphosphonium (TPP) group is the most widely used vector targeted to mitochondria. Previously, the length of the alkyl linker was varied as well as structural modifications in the TPP phenyl rings to obtain the optimal therapeutic effect of a pharmacophore conjugated with a lipophilic cation. In the present work, we synthesized butyltriphenylphosphonium cations halogenated and methylated in phenyl rings (C
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- 2022
17. Peptide-induced membrane elastic deformations decelerate gramicidin dimer-monomer equilibration
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Oleg V. Batishchev, Sergey A. Akimov, Tatyana I. Rokitskaya, Yuri N. Antonenko, Elena A. Kotova, and Oleg V. Kondrashov
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Thermodynamic equilibrium ,Dimer ,Lipid Bilayers ,Relaxation (NMR) ,Gramicidin ,Biophysics ,Kinetic scheme ,Articles ,Ion Channels ,chemistry.chemical_compound ,Membrane ,Monomer ,chemistry ,Peptides ,Lipid bilayer ,Dimerization - Abstract
Gramicidin A (gA) is a hydrophobic pentadecapeptide readily incorporating into a planar bilayer lipid membrane (BLM), thereby inducing a large macroscopic current across the BLM. This current results from ion-channel formation due to head-to-head transbilayer dimerization of gA monomers with rapidly established monomer-dimer equilibrium. Any disturbance of the equilibrium, e.g., by sensitized photoinactivation of a portion of gA monomers, causes relaxation toward a new equilibrium state. According to previous studies, the characteristic relaxation time of the gA-mediated electric current decreases as the current increases upon elevating the gA concentration in the membrane. Here, we report data on the current relaxation kinetics for gA analogs with N-terminal valine replaced by glycine or tyrosine. Surprisingly, the relaxation time increased rather than decreased upon elevation of the total membrane conductance induced by these gA analogs, thus contradicting the classical kinetic scheme. We developed a general theoretical model that accounts for lateral interaction of monomers and dimers mediated by membrane elastic deformations. The modified kinetic scheme of the gramicidin dimerization predicts the reverse dependence of the relaxation time on membrane conductance for gA analogs, with a decreased dimerization constant that is in a good agreement with our experimental data. The equilibration process may be also modulated by incorporation of other peptides (“impurities”) into the lipid membrane.
- Published
- 2021
18. Photodynamic activity rather than drilling causes membrane damage by a light-powered molecular nanomotor
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Alexander M. Firsov, Juergen Pfeffermann, Anton S. Benditkis, Tatyana I. Rokitskaya, Anton S. Kozlov, Elena A. Kotova, Alexander A. Krasnovsky, Peter Pohl, and Yuri N. Antonenko
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Radiation ,Radiological and Ultrasound Technology ,Biophysics ,Radiology, Nuclear Medicine and imaging - Abstract
The chase toward endowing chemical compounds with machine-like functions mimicking those of biological molecular machineries has yielded a variety of artificial molecular motors (AMMs). Pharmaceutical applications of photoexcited monomolecular unidirectionally-rotating AMMs have been envisioned in view of their ability to permeabilize biological membranes. Nonetheless, the mechanical properties of lipid membranes render the proposed drilling activity of AMMs doubtful. Here, we show that singlet oxygen released by a photoexcited "molecular drill" oxidized unsaturated lipids composing giant unilamellar vesicles. In contrast, giant liposomes built of saturated lipids were inert to AMM photoactuation. The AMM did not mechanically destroy gramicidin A ion channels in planar bilayer lipid membranes but instead photoinactivated them. Sodium azide, a singlet oxygen quencher, reduced both AMM-mediated light-induced dye release from unsaturated large unilamellar vesicles and protected gramicidin A from photoinactivation. Upon additional consideration of the underlying bilayer mechanics, we conclude that AMMs' envisioned therapeutic and pharmaceutical applications rely on their photodynamic activity rather than their nanomechanical drilling abilities.
- Published
- 2022
19. Trialkyl(vinyl)phosphonium Chlorophenol Derivatives as Potent Mitochondrial Uncouplers and Antibacterial Agents
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Pavel A. Nazarov, Vladimir F. Mironov, Lyudmila S. Khailova, Konstantin S. Usachev, Tatyana I. Rokitskaya, Daut R. Islamov, Yuri N. Antonenko, Elena A. Kotova, D. A. Tatarinov, and Natalia V. Terekhova
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Chlorophenol ,chemistry.chemical_classification ,Membrane potential ,General Chemical Engineering ,General Chemistry ,Mitochondrion ,Medicinal chemistry ,Article ,chemistry.chemical_compound ,Chemistry ,Membrane ,chemistry ,Reagent ,Phosphonium ,QD1-999 ,Phosphine ,Alkyl - Abstract
Trialkyl phosphonium derivatives of vinyl-substituted p-chlorophenol were synthesized here by a recently developed method of preparing quaternary phosphonium salts from phosphine oxides using Grignard reagents. All the derivatives with a number (n) of carbon atoms in phosphonium alkyl substituents varying from 4 to 7 showed pronounced uncoupling activity in isolated rat liver mitochondria at micromolar concentrations, with a tripentyl derivative being the most effective both in accelerating respiration and causing membrane potential collapse, as well as in provoking mitochondrial swelling in a potassium-acetate medium. Remarkably, the trialkyl phosphonium derivatives with n from 4 to 7 also proved to be rather potent antibacterial agents. Methylation of the chlorophenol hydroxyl group suppressed the effects of P555 and P444 on the respiration and membrane potential of mitochondria but not those of P666, thereby suggesting a mechanistic difference in the mitochondrial uncoupling by these derivatives, which was predominantly protonophoric (carrier-like) in the case of P555 and P444 but detergent-like with P666. The latter was confirmed by the carboxyfluorescein leakage assay on model liposomal membranes.
- Published
- 2021
20. Electrophysiological Characterization of Microbial Rhodopsin Transport Properties: Electrometric and ΔpH Measurements Using Planar Lipid Bilayer, Collodion Film, and Fluorescent Probe Approaches
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Tatyana I, Rokitskaya, Nina L, Maliar, Sergey A, Siletsky, Valentin, Gordeliy, and Yuri N, Antonenko
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Rhodopsin ,Light ,Bacteriorhodopsins ,Lipid Bilayers ,Rhodopsins, Microbial ,Collodion ,Proton-Motive Force ,Fluorescent Dyes - Abstract
Electrophysiological approaches to the study of the activity of retinal-containing protein bacteriorhodopsin (bR) or other proteins of this family are based usually on measurements of electrical current through a planar bilayer lipid membrane (BLM) with proteoliposomes attached to the BLM surface at one side of the membrane. Here, we describe the measurements of the pumping activity of bR and channelrhodopsin 2 (ChR2) with special attention to the study of voltage dependence of the light-induced currents. Strong voltage dependence of ChR2 suggests light-triggered ion channel activity of ChR2. We also describe electrophysiological measurements with the help of collodion film instead of BLM for the measurements of fast stages of a rhodopsin photocycle as well as the estimation of the activity of proteoliposomes without a macro membrane using fluorescent probes such as oxonol VI or 9-aminoacridine.
- Published
- 2022
21. Ester-stabilized phosphorus ylides as protonophores on bilayer lipid membranes, mitochondria and chloroplasts
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Roman S. Kirsanov, Ljudmila S. Khailova, Tatyana I. Rokitskaya, Iliuza R. Iaubasarova, Pavel A. Nazarov, Alisa A. Panteleeva, Konstantin G. Lyamzaev, Lyudmila B. Popova, Galina A. Korshunova, Elena A. Kotova, and Yuri N. Antonenko
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Electrochemistry ,Biophysics ,General Medicine ,Physical and Theoretical Chemistry - Published
- 2023
22. Alkyl esters of 7-hydroxycoumarin-3-carboxylic acid as potent tissue-specific uncouplers of oxidative phosphorylation: Involvement of ATP/ADP translocase in mitochondrial uncoupling
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Vladimir S. Krasnov, Roman S. Kirsanov, Ljudmila S. Khailova, Lyudmila B. Popova, Konstantin G. Lyamzaev, Alexander M. Firsov, Galina A. Korshunova, Elena A. Kotova, and Yuri N. Antonenko
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Uncoupling Agents ,Aldehyde Dehydrogenase, Mitochondrial ,Biophysics ,Esters ,Mitochondria, Liver ,Biochemistry ,Mitochondria, Heart ,Oxidative Phosphorylation ,Rats ,Adenosine Triphosphate ,HEK293 Cells ,Animals ,Humans ,Umbelliferones ,Molecular Biology ,Mitochondrial ADP, ATP Translocases - Abstract
An impressive body of evidence has been accumulated now on sound beneficial effects of mitochondrial uncouplers in struggling with the most dangerous pathologies such as cancer, infective diseases, neurodegeneration and obesity. To increase their efficacy while gaining further insight in the mechanism of the uncoupling action has been remaining a challenge. Encouraged by our previous promising results on lipophilic derivatives of 7-hydroxycoumarin-4-acetic acid (UB-4 esters), here, we use a 7-hydroxycoumarin-3-carboxylic acid scaffold to synthesize a new series of 7-hydroxycoumarin (umbelliferone, UB)-derived uncouplers of oxidative phosphorylation - alkyl esters of umbelliferone-3-carboxylic acid (UB-3 esters) with varying carbon chain length. Compared to the UB-4 derivatives, UB-3 esters proved to be stronger uncouplers: the most effective of them caused a pronounced increase in the respiration rate of isolated rat heart mitochondria (RHM) at submicromolar concentrations. Both of these series of UB derivatives exhibited a striking difference between their uncoupling patterns in mitochondria isolated from liver and heart or kidney, namely: a pronounced but transient decrease in membrane potential, followed by its recovery, was observed after the addition of these compounds to isolated rat liver mitochondria (RLM), while the depolarization of RHM and rat kidney mitochondria (RKM) was rather stable under the same conditions. Interestingly, partial reversal of this depolarization in RHM and RKM was caused by carboxyatractyloside, an inhibitor of ATP/ADP translocase, thereby pointing to the involvement of this mitochondrial membrane protein in the uncoupling activity of both UB-3 and UB-4 esters. The fast membrane potential recovery in RLM uncoupled by the addition of the UB esters was apparently associated with hydrolysis of these compounds, catalyzed by mitochondrial aldehyde dehydrogenase (ALDH2), being in high abundance in liver compared to other tissues. Protonophoric properties of the UB derivatives in isolated mitochondria were confirmed by measurements of RHM swelling in the presence of potassium acetate. In model bilayer lipid membranes (liposomes), proton-carrying activity of UB-3 esters was demonstrated by measuring fluorescence response of the pH-dependent dye pyranine. Electrophysiological experiments on identified neurons from Lymnaea stagnalis demonstrated low neurotoxicity of UB-3 esters. Resazurin-based cell viability assay showed low toxicity of UB-3 esters to HEK293 cells and primary human fibroblasts. Thus, the present results enable us to consider UB-3 esters as effective tissue-specific protonophoric mitochondrial uncouplers.
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- 2022
23. Rhodopsin Channel Activity Can Be Evaluated by Measuring the Photocurrent Voltage Dependence in Planar Bilayer Lipid Membranes
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Nina Maliar, Valentin Gordeliy, Kirill Kovalev, Oleksandr Volkov, Tatyana I. Rokitskaya, and Yuri N. Antonenko
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Photocurrent ,Liposome ,Ion Transport ,biology ,Chemistry ,Polarity (physics) ,Protonophore ,Proteolipids ,Lipid Bilayers ,Biophysics ,Bacteriorhodopsin ,General Medicine ,Biochemistry ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Membrane ,Channelrhodopsins ,Rhodopsin ,Bacteriorhodopsins ,biology.protein ,Geriatrics and Gerontology ,Electric current - Abstract
The studies of the functional properties of retinal-containing proteins often include experiments in model membrane systems, e.g., measurements of electric current through planar bilayer lipid membranes (BLMs) with proteoliposomes adsorbed on one of the membrane surfaces. However, the possibilities of this method have not been fully explored yet. We demonstrated that the voltage dependence of stationary photocurrents for two light-sensitive proteins, bacteriorhodopsin (bR) and channelrhodopsin 2 (ChR2), in the presence of protonophore had very different characteristics. In the case of the bR (proton pump), the photocurrent through the BLM did not change direction when the polarity of the applied voltage was switched. In the case of the photosensitive channel protein ChR2, the photocurrent increased with the increase in voltage and the current polarity changed with the change in the voltage polarity. The protonophore 4,5,6,7-tetrachloro-2-trifluoromethyl benzimidazole (TTFB) was more efficient in the maximizing stationary photocurrents. In the presence of carbonyl cyanide-m-chlorophenylhydrazone (CCCP), the amplitude of the measured photocurrents for bR significantly decreased, while in the case of ChR2, the photocurrents virtually disappeared. The difference between the effects of TTFB and CCCP was apparently due to the fact that, in contrast to TTFB, CCCP transfers protons across the liposome membranes with a higher rate than through the decane-containing BLM used as a surface for the proteoliposome adsorption.
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- 2021
24. Novel pH-Sensitive Microbial Rhodopsin from Sphingomonas paucimobilis
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Lada E. Petrovskaya, Dmitry A. Dolgikh, Mikhail P. Kirpichnikov, Dmitrii Zabelskii, Tatyana I. Rokitskaya, Nina Maliar, Valentin Gordeliy, Ivan Okhrimenko, Petr Popov, Kirill Kovalev, Yuri N. Antonenko, Alexey Alekseev, and D V Soloviov
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0303 health sciences ,Sphingomonas paucimobilis ,biology ,Chemistry ,Aerobic bacteria ,030302 biochemistry & molecular biology ,Biophysics ,General Chemistry ,General Medicine ,biology.organism_classification ,Biochemistry ,Micelle ,03 medical and health sciences ,Membrane protein ,Rhodopsin ,biology.protein ,Spar ,Proteobacteria ,Ion transporter ,030304 developmental biology - Abstract
This work provides the first characteristics of the rhodopsin SpaR from Sphingomonas paucimobilis, aerobic bacteria associated with opportunistic infections. The sequence analysis of SpaR has shown that this protein has unusual DTS motif which has never reported in rhodopsins from Proteobacteria. We report that SpaR operates as an outward proton pump at low pH; however, proton pumping is almost absent at neutral and alkaline pH. The photocycle of this rhodopsin in detergent micelles slows down with an increase in pH because of longer Schiff base reprotonation. Our results show that the novel microbial ion transporter SpaR of interest both as an object for basic research of membrane proteins and as a promising optogenetic tool.
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- 2020
25. Study of Interaction of Fluorescent Cytochrome C with Liposomes, Mitochondria, and Mitoplasts by Fluorescence Correlation Spectroscopy
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Mikhail P. Kirpichnikov, Rita V. Chertkova, Yuri N. Antonenko, I. D. Gusev, Alexander M. Firsov, Dmitry A. Dolgikh, and Elena A. Kotova
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0301 basic medicine ,Liposome ,biology ,010405 organic chemistry ,Cytochrome c ,Organic Chemistry ,Fluorescence correlation spectroscopy ,Mitochondrion ,01 natural sciences ,Biochemistry ,Fluorescence ,0104 chemical sciences ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Membrane ,chemistry ,Biophysics ,Cardiolipin ,biology.protein ,Binding site - Abstract
Here, we studied the interaction of Cys-substituted (G56C) cytochrome c labeled with sulfocyanin-3 fluorescent dye (fCyt) with artificial and natural lipid membranes by using fluorescence correlation spectroscopy (FCS). Compared to mitochondria, mitoplasts were shown to have more fCyt binding sites with a lower affinity for this protein. The fCyt affinity for cardiolipin-containing liposomes depended on the content of cardiolipin in liposomes and decreased upon raising the ionic strength of the solution. A high value of the constant of the fCyt binding with mitochondria could be explained by the presence of specific binding sites for this protein on the mitochondrial outer membrane surface. This explanation is confirmed by observation of more efficient displacement of fluorescent cytochrome c by the unlabeled mutant variant K8T than by the WT protein, whereas in mitoplasts and liposomes the WT protein displaced fCyt more efficiently than K8T.
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- 2020
26. Inhibition of respiratory complex I by 6-ketocholestanol: Relevance to recoupling action in mitochondria
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Vera G. Grivennikova, Ljudmila S. Khailova, Tatyana V. Zharova, Elena A. Kotova, and Yuri N. Antonenko
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Carbonyl Cyanide m-Chlorophenyl Hydrazone ,Electron Transport Complex I ,Biophysics ,Animals ,Cattle ,Cell Biology ,Biochemistry ,Ketocholesterols ,Mitochondria ,Rats - Abstract
6-Ketocholestanol (kCh) is known as a mitochondrial recoupler, i.e. it abolishes uncoupling of mitochondria by such potent agents as carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and 3,5-di(tert-butyl)-4-hydroxybenzylidenemalononitril (SF6847) [Starkov et al., 1997]. Here, we report data on the kCh-induced inhibition of both NADH-oxidase and NADH-ubiquinone oxidoreductase activities of the respiratory complex I in bovine heart submitochondrial particles (SMP). Based on the absence of such inhibition with hexaammineruthenium (III) (HAR) as the complex I electron acceptor, the kCh effect could be associated with the ubiquinone-binding centre of this respiratory enzyme. In isolated rat liver mitochondria (RLM), kCh inhibited oxygen consumption with the glutamate/malate, substrates of NAD-linked dehydrogenases, while no inhibition of RLM respiration was observed with succinate, in agreement with the absence of the kCh effect on the succinate oxidase activity in SMP. Three kCh analogs (cholesterol, 6α-hydroxycholesterol, and 5α,6α-epoxycholesterol) exhibited no effect on the NADH oxidase activities in both SMP and RLM. Importantly, the kCh analogs were ineffective in the recoupling of RLM treated with CCCP or SF6847. Therefore, interaction of kCh with the complex I may be involved in the kCh-mediated mitochondrial recoupling.
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- 2022
27. Rate of translocation across lipid bilayer of triphenylphosphonium-linked salinomycin derivatives contributes significantly to their K
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Yuri N, Antonenko, Marta, Jędrzejczyk, Tatyana I, Rokitskaya, Ljudmila S, Khailova, Elena A, Kotova, and Adam, Huczyński
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Lipid Bilayers ,Anti-Bacterial Agents ,Mitochondria ,Pyrans - Abstract
Salinomycin (SAL), a polyether antibiotic exerting K
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- 2022
28. Electrophysiological Characterization of Microbial Rhodopsin Transport Properties: Electrometric and ΔpH Measurements Using Planar Lipid Bilayer, Collodion Film, and Fluorescent Probe Approaches
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Tatyana I. Rokitskaya, Nina L. Maliar, Sergey A. Siletsky, Valentin Gordeliy, and Yuri N. Antonenko
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- 2022
29. Alkyl esters of umbelliferone-4-acetic acid as protonophores in bilayer lipid membranes and ALDH2-dependent soft uncouplers in rat liver mitochondria
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Vladimir S. Krasnov, Roman S. Kirsanov, Ljudmila S. Khailova, Alexander M. Firsov, Pavel A. Nazarov, Vadim N. Tashlitsky, Galina A. Korshunova, Elena A. Kotova, and Yuri N. Antonenko
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Uncoupling Agents ,Aldehyde Dehydrogenase, Mitochondrial ,Lipid Bilayers ,Electrochemistry ,Biophysics ,Animals ,Esters ,Mitochondria, Liver ,General Medicine ,Umbelliferones ,Physical and Theoretical Chemistry ,Acetic Acid ,Rats - Abstract
A great variety of coumarin-related compounds, both natural and synthetic, being often brightly fluorescent, have shown themselves beneficial in medicine for both therapeutic and imaging purposes. Here, in search for effective uncouplers of oxidative phosphorylation, we synthesized a series of 7-hydroxycoumarin (umbelliferone, UB) derivatives combining rather high membrane affinity with the presence of a hydroxyl group deprotonable at physiological pH - alkyl esters of umbelliferone-4-acetic acid (UB-4 esters) differing in alkyl chain length. Addition of UB-4 esters to isolated rat liver mitochondria (RLM) resulted in their rapid depolarization, unexpectedly followed by membrane potential recovery on a minute time scale. According to TLC and HPLC data, incubation of RLM with UB-4 esters caused their hydrolysis, which led to disappearance of the uncoupling activity (recoupling). Both mitochondrial recoupling and hydrolysis of UB-4 esters were suppressed by inhibitors of mitochondrial aldehyde dehydrogenase (ALDH2), disulfiram and daidzin, thus pointing to the involvement of this enzyme in the recoupling of RLM incubated with UB-4 esters. The protonophoric mechanism of mitochondrial uncoupling by UB-4 esters was proved in experiments with artificial bilayer lipid membranes (BLM): these compounds induced proton-selective electrical current across planar BLM and caused dissipation of pH gradient on liposomes. UB-4 esters showed antibacterial activity against Bacillus subtilis, Staphylococcus aureus and Mycobacterium smegmatis.
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- 2021
30. Fifty Years of Research on Protonophores: Mitochondrial Uncoupling As a Basis for Therapeutic Action
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Elena A. Kotova and Yuri N. Antonenko
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General Engineering ,General Earth and Planetary Sciences ,General Environmental Science - Abstract
Protonophores are compounds capable of electrogenic transport of protons across membranes. Protonophores have been intensively studied over the past 50 years owing to their ability to uncouple oxidation and phosphorylation in mitochondria and chloroplasts. The action mechanism of classical uncouplers, such as DNP and CCCP, in mitochondria is believed to be related to their protonophoric activity; i.e., their ability to transfer protons across the lipid part of the mitochondrial membrane. Given the recently revealed deviations in the correlation between the protonophoric activity of some uncouplers and their ability to stimulate mitochondrial respiration, this review addresses the involvement of some proteins of the inner mitochondrial membrane, such as the ATP/ADP antiporter, dicarboxylate carrier, and ATPase, in the uncoupling process. However, these deviations do not contradict the Mitchell theory but point to a more complex nature of the interaction of DNP, CCCP, and other uncouplers with mitochondrial membranes. Therefore, a detailed investigation of the action mechanism of uncouplers is required for a more successful pharmacological use, including their antibacterial, antiviral, anticancer, as well as cardio-, neuro-, and nephroprotective effects.
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- 2021
31. Mitochondrial Uncoupling Proteins (UCP1-UCP3) and Adenine Nucleotide Translocase (ANT1) Enhance the Protonophoric Action of 2,4-Dinitrophenol in Mitochondria and Planar Bilayer Membranes
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Yuri N. Antonenko, Elena E. Pohl, Olga Jovanovic, Elena A. Kotova, Zlatko Brkljača, Sanja Škulj, Mario Vazdar, Khailova Ls, Kristina Žuna, and Jürgen Kreiter
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Protonophore ,Lipid Bilayers ,Mitochondria, Liver ,chemical and pharmacologic phenomena ,Oxidative phosphorylation ,Mitochondrion ,Biochemistry ,Microbiology ,Article ,2,4-Dinitrophenol ,Membrane Potentials ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Animals ,Molecular Biology ,030304 developmental biology ,UCP3 ,mitochondrial uncoupler ,Membrane potential ,chemistry.chemical_classification ,0303 health sciences ,Biotechnology in Biomedicine (natural science, biomedicine and healthcare, bioethics area ,organic chemicals ,protonophore ,membrane potential ,proton conductance ,artificial membranes ,molecular dynamics simulations ,QR1-502 ,Amino acid ,Rats ,Membrane ,chemistry ,Biophysics ,Mitochondrial Uncoupling Proteins ,Mitochondrial ADP, ATP Translocases ,030217 neurology & neurosurgery - Abstract
2,4-Dinitrophenol (DNP) is a classic uncoupler of oxidative phosphorylation in mitochondria which is still used in “diet pills”, despite its high toxicity and lack of antidotes. DNP increases the proton current through pure lipid membranes, similar to other chemical uncouplers. However, the molecular mechanism of its action in the mitochondria is far from being understood. The sensitivity of DNP’s uncoupling action in mitochondria to carboxyatractyloside, a specific inhibitor of adenine nucleotide translocase (ANT), suggests the involvement of ANT and probably other mitochondrial proton-transporting proteins in the DNP’s protonophoric activity. To test this hypothesis, we investigated the contribution of recombinant ANT1 and the uncoupling proteins UCP1-UCP3 to DNP-mediated proton leakage using the well-defined model of planar bilayer lipid membranes. All four proteins significantly enhanced the protonophoric effect of DNP. Notably, only long-chain free fatty acids were previously shown to be co-factors of UCPs and ANT1. Using site-directed mutagenesis and molecular dynamics simulations, we showed that arginine 79 of ANT1 is crucial for the DNP-mediated increase of membrane conductance, implying that this amino acid participates in DNP binding to ANT1.
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- 2021
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32. Mitochondrial uncoupling proteins (UCP1-UCP3) and adenine nucleotide translocase (ANT1) enhance protonophoric action of 2,4-dinitrophenol in mitochondria and planar bilayer membranes
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Kristina Žuna, Olga Jovanović, Ljudmila S. Khailova, Sanja Škulj, Zlatko Brkljača, Jürgen Kreiter, Elena A. Kotova, Mario Vazdar, Yuri N. Antonenko, and Elena E. Pohl
- Subjects
organic chemicals ,dinitrophenol ,chemical and pharmacologic phenomena ,protonophore ,membrane potential ,proton conductance ,mitochondrial uncoupler - Abstract
2, 4-dinitrophenol (DNP) is a classic uncoupler of oxidative phosphorylation in mitochondria and directly increases the metabolic rate by increasing the body’s heat generation. It is still used as a “diet pill” despite its high toxicity and lack of antidotes. DNP increases the proton current through the pure lipid membranes similar to other chemical uncouplers. However, the molecular mechanism of its action in mitochondria is far from being understood. Since DNP´s protonophoric function in mitochondria is known to be sensitive to carboxyatractyloside, a specific inhibitor of adenine nucleotide translocase (ANT), we hypothesized that DNP modifies the activity of ANT and other mitochondrial proton-transporting proteins. To test this hypothesis, we investigated the contribution of recombinant ANT1 or uncoupling proteins UCP2 and UCP3 to the DNP-mediated proton leak using the well-defined model of the planar bilayer membranes. All three proteins significantly enhanced the DNP-mediated proton transport, an activity previously known to happen only in the presence of long-chain free fatty acids. Using site-directed mutagenesis and molecular dynamic simulations we have shown that arginine 79 of ANT1 is crucial for the DNP-mediated increase of the membrane conductance, implying that this amino acid participates in DNP binding to ANT1.  
- Published
- 2021
- Full Text
- View/download PDF
33. Mitochondrial proton-transporting proteins enhance uncoupling action of 2,4-dinitrophenol in mitochondria and planar lipid bilayers
- Author
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Kristina Žuna, Olga Jovanović, Ljudmila S. Khailova, Sanja Škulj, Zlatko Brkljača, Elena A. Kotova, Mario Vazdar, Yuri N. Antonenko, and Elena E. Pohl
- Subjects
dinitrophenol ,chemical and pharmacologic phenomena ,protonophore ,membrane potential ,proton conductance ,mitochondrial uncoupler - Abstract
2, 4-dinitrophenol (DNP) is a classic uncoupler of oxidative phosphorylation in mitochondria and directly increases the metabolic rate by increasing the body’s heat generation. It is still used as a “diet pill” despite its high toxicity and lack of antidotes. DNP increases the proton current through the pure lipid membranes similar to other chemical uncouplers. However, the molecular mechanism of its action in mitochondria is far from being understood. Since DNP´s protonophoric function in mitochondria is known to be sensitive to carboxyatractyloside, a specific inhibitor of adenine nucleotide translocase (ANT), we hypothesized that DNP modifies the activity of ANT and other mitochondrial proton-transporting proteins. To test this hypothesis, we investigated the contribution of recombinant ANT1 or uncoupling proteins UCP2 and UCP3 to the DNP-mediated proton leak using the well-defined model of the planar bilayer membranes. All three proteins significantly enhanced the DNP-mediated proton transport, an activity previously known to happen only in the presence of long-chain free fatty acids. Using site-directed mutagenesis and molecular dynamic simulations we have shown that arginine 79 of ANT1 is crucial for the DNP-mediated increase of the membrane conductance, implying that this amino acid participates in DNP binding to ANT1.  
- Published
- 2021
- Full Text
- View/download PDF
34. Triphenilphosphonium Analogs of Chloramphenicol as Dual-Acting Antimicrobial and Antiproliferating Agents
- Author
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Alena Paleskava, Etna Abad, Ilya A. Osterman, Pavel A. Nazarov, G. I. Makarov, Susumu Kajiwara, Yuri N. Antonenko, Dmitrii A. Lukianov, Zimfira Z Khairullina, Inna A. Volynkina, Julia A. Pavlova, Somay Y Murayama, Alex Lyakhovich, Dmitry A. Skvortsov, Natalia V. Sumbatyan, Andrey G Tereshchenkov, Alexey A. Bogdanov, Andrey L. Konevega, Institut Català de la Salut, [Pavlova JA, Khairullina ZZ] Department of Chemistry, Lomonosov Moscow State University, 119991 Moscow, Russia. [Tereshchenkov AG] A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia. [Nazarov PA] A.N. Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, 119992 Moscow, Russia. Laboratory of Molecular Genetics, Moscow Institute of Physics and Technology, 141700 Dolgoprudny, Russia. [Lukianov DA] Center of Life Sciences, Skolkovo Institute of Science and Technology, 143028 Skolkovo, Russia. [Volynkina IA] School of Bioengineering and Bioinformatics, Lomonosov Moscow State University, 119992 Moscow, Russia. [Lyakhovich A] Institute of Molecular Biology and Biophysics, Federal Research Center of Fundamental and Translational Medicine, 630117 Novosibirsk, Russia. Vall d’Hebron Institut de Recerca (VHIR), Barcelona, Spain, and Vall d'Hebron Barcelona Hospital Campus
- Subjects
0301 basic medicine ,Microbiology (medical) ,antiproliferative activity ,chloramphenicol ,bacterial ribosome ,Medicaments antiinfecciosos - Ús terapèutic ,Bacteria [ORGANISMS] ,RM1-950 ,Mitochondrion ,Otros calificadores::/efectos de los fármacos [Otros calificadores] ,Biochemistry ,Microbiology ,Ribosome ,Article ,03 medical and health sciences ,In vivo ,Medicaments - Efectes fisiològics ,medicine ,Protein biosynthesis ,biochemistry ,Pharmacology (medical) ,Other subheadings::/therapeutic use [Other subheadings] ,Other subheadings::/drug effects [Other subheadings] ,General Pharmacology, Toxicology and Pharmaceutics ,alkyl(triphenyl)phosphonium ,Chemical Actions and Uses::Pharmacologic Actions::Therapeutic Uses::Anti-Infective Agents [CHEMICALS AND DRUGS] ,030102 biochemistry & molecular biology ,biology ,antibiotic activity ,Otros calificadores::/uso terapéutico [Otros calificadores] ,Chemistry ,Bacterial ribosome ,Chloramphenicol ,acciones y usos químicos::acciones farmacológicas::usos terapéuticos::antiinfecciosos [COMPUESTOS QUÍMICOS Y DROGAS] ,Translation (biology) ,molecular dynamics simulations ,DUAL (cognitive architecture) ,Antimicrobial ,biology.organism_classification ,In vitro ,030104 developmental biology ,Infectious Diseases ,Therapeutics. Pharmacology ,Ribosomes ,Bacteria [ORGANISMOS] ,Bacteria ,medicine.drug - Abstract
Activitat antibiòtica; Ribosoma bacterià; Simulacions de dinàmica molecular Actividad antibiótica; Ribosoma bacteriano; Simulaciones de dinámica molecular Antibiotic activity; Bacterial ribosome; Molecular dynamics simulations In the current work, in continuation of our recent research, we synthesized and studied new chimeric compounds, including the ribosome-targeting antibiotic chloramphenicol (CHL) and the membrane-penetrating cation triphenylphosphonium (TPP), which are linked by alkyl groups of different lengths. Using various biochemical assays, we showed that these CAM-Cn-TPP compounds bind to the bacterial ribosome, inhibit protein synthesis in vitro and in vivo in a way similar to that of the parent CHL, and significantly reduce membrane potential. Similar to CAM-C4-TPP, the mode of action of CAM-C10-TPP and CAM-C14-TPP in bacterial ribosomes differs from that of CHL. By simulating the dynamics of CAM-Cn-TPP complexes with bacterial ribosomes, we proposed a possible explanation for the specificity of the action of these analogs in the translation process. CAM-C10-TPP and CAM-C14-TPP more strongly inhibit the growth of the Gram-positive bacteria, as compared to CHL, and suppress some CHL-resistant bacterial strains. Thus, we have shown that TPP derivatives of CHL are dual-acting compounds targeting both the ribosomes and cellular membranes of bacteria. The TPP fragment of CAM-Cn-TPP compounds has an inhibitory effect on bacteria. Moreover, since the mitochondria of eukaryotic cells possess qualities similar to those of their prokaryotic ancestors, we demonstrate the possibility of targeting chemoresistant cancer cells with these compounds. This research was funded by RFBR [grants 20-04-00873 to N.V.S. (synthesis of analogs, binding assays, in vitro translation), 20-015-00537 to P.A.N. (potential measurement, screening of TolC-containing transporters), and 20-54-76002 to I.A.O. (toeprinting and in vitro translation)], President grant MD 2626.2021.1.4 to I.A.O. (bacteria inhibition assays), grants from the Instituto de Salud Carlos III: PI17/02087 to A.L. (cancer cell proliferation assays) by the Ministry of Science and Higher Education of the Russian Federation [grant FENU-2020-0019 to G.I.M. (molecular dynamics simulations)] and by the Government of the Russian Federation [No. AAAA-A17-117120570004-6 to A.A.B.].
- Published
- 2021
35. An Abnormally High Closing Potential of the OMPF Porin Channel from Yersinia Ruckeri: The Role of Charged Residues and Intramolecular Bonds
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Galina N. Likhatskaya, V. A. Khomenko, Olga D. Novikova, Elena Zelepuga, D. K. Chistyulin, O. Yu. Portnyagina, and Yuri N. Antonenko
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Yersinia ruckeri ,0301 basic medicine ,biology ,Chemistry ,Bilayer ,030106 microbiology ,Conductance ,Charge density ,biology.organism_classification ,Biochemistry ,03 medical and health sciences ,Electrophysiology ,Barrel ,030104 developmental biology ,voltage-dependent gating ,Porin ,bilayer lipid membranes ,Biophysics ,Molecular Medicine ,pore-forming proteins ,Bacterial outer membrane ,Molecular Biology ,Research Article ,Biotechnology - Abstract
Electrophysiological experiments on bilayer lipid membranes showed that the isolated outer membrane major porin of Yersinia ruckeri (YrOmpF) exhibits activity typical of porins from Gram-negative bacteria, forming channels with a mean conductance of 230 pS (in 0.1 M KCl) and slight asymmetry with respect to the applied voltage. Under acidic conditions (up to pH = 3.0), there was no significant decrease in the total conductance of the YrOmpF channel reconstituted into the bilayer. The studied channel significantly differed from the porins of other bacteria by high values of its critical closing potential (Vc): Vc = 232 mV at pH = 7.0 and Vc = 164 mV at pH = 5.0. A theoretical model of the YrOmpF spatial structure was used for the analysis of the charge distribution in the mouth and inside the channel to explain these properties and quantitatively assess the bonds between the amino acid residues in the L3 loop and on the inner wall of the barrel. The parameters of YrOmpF were compared with those of the classical OmpF porin from E. coli. The results of electrophysiological experiments and theoretical analysis are discussed in terms of the mechanism for voltage-dependent closing of porin channels.
- Published
- 2019
36. Zwitterionic Protonophore Derived from 2-(2-Hydroxyaryl)alkenylphosphonium as an Uncoupler of Oxidative Phosphorylation
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Elena A. Kotova, Egor Y. Plotnikov, Natalia V. Terekhova, Lyudmila S. Khailova, Tatyana I. Rokitskaya, Dmitry A. Tatarinov, Yuri N. Antonenko, and Dmitry B. Zorov
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Stereochemistry ,Protonophore ,Biomedical Engineering ,Pharmaceutical Science ,Mitochondria, Liver ,Bioengineering ,02 engineering and technology ,Oxidative phosphorylation ,Mitochondrion ,Methylation ,01 natural sciences ,Oxidative Phosphorylation ,Membrane Potentials ,chemistry.chemical_compound ,Adenosine Triphosphate ,Organophosphorus Compounds ,Animals ,Phosphonium ,Pharmacology ,Membrane potential ,ATP synthase ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,021001 nanoscience & nanotechnology ,Rats ,0104 chemical sciences ,Membrane ,Zwitterion ,biology.protein ,Protons ,0210 nano-technology ,Biotechnology - Abstract
2-(2-Hydroxyaryl)alkenylphosphonium salts (here coined as PPR) representing derivatives of quaternary phosphonium with two phenyl (P) and one alkyl (R) substituents linked through alkenyl bridge to substituted phenol were applied here to planar bilayer lipid membranes (BLM), isolated mitochondria, and cell culture. PPR with six carbon atoms in R (PP6) induced proton-selective currents across BLM and caused mitochondrial uncoupling. In particular, PP6 at submicromolar concentrations accelerated respiration, decreased membrane potential, and reduced ATP synthesis in isolated rat liver mitochondria (RLM). Methylation of a hydroxyl group substantially suppressed the protonophoric activity of PP6 on BLM and its uncoupling potency in RLM. Of note, the methylated derivative PP6-OMe was synthesized here via a new synthetic route including cyclization of PP6 with subsequent ring opening. PPR were considered as protonophoric uncouplers of a zwitterionic type, capable of penetrating membranes both as a zwitterion composed of a deprotonated phenol and a cationic quaternary phosphonium, and as a protonated cation. The protonophoric and uncoupling properties of PPR found here were speculated to account for their strong antibacterial activity described previously.
- Published
- 2019
37. Mechanism of action of an old antibiotic revisited: Role of calcium ions in protonophoric activity of usnic acid
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Khailova Ls, Yuri N. Antonenko, Ekaterina S. Nosikova, Pavel A. Nazarov, Olga A. Luzina, Nariman F. Salakhutdinov, Tatyana I. Rokitskaya, and Elena A. Kotova
- Subjects
Protonophore ,Lipid Bilayers ,Biophysics ,Ionophore ,chemistry.chemical_element ,Mitochondria, Liver ,Mitochondrion ,Calcium ,Biochemistry ,chemistry.chemical_compound ,medicine ,Animals ,Calcimycin ,Benzofurans ,Membrane Potential, Mitochondrial ,Membrane potential ,Ion Transport ,Usnic acid ,Cell Biology ,Anti-Bacterial Agents ,Rats ,Membrane ,Mechanism of action ,chemistry ,medicine.symptom ,Bacillus subtilis - Abstract
Usnic acid (UA), an old antibiotic and one of the first described mitochondrial uncouplers, has demonstrated many beneficial activities, such as antimicrobial, antiviral, antitumour and anti-inflammatory properties. Here, we performed a thorough investigation of effects of usnic acid and its analogues on artificial planar bilayer lipid membrane (BLM), rat liver mitochondria and bacteria. Surprisingly enough, all of the three hydroxyl groups of UA appeared to be involved in its proton-shuttling activity on BLM. We ascribed this fact to an ability of UA to form complexes with calcium ions, aiding it in cycling protons across the membrane. Actually, the addition of calcium ions markedly stimulated the UA-induced electrical current across BLM. By using the calcium ionophore A23187, we proved the involvement of calcium ions in the UA uncoupling action on isolated rat liver mitochondria. The calcium-chelating property of UA was demonstrated here by the method of extracting metal ions into a hydrophobic phase. Modification of any of the hydroxyl groups in UA dramatically reduced not only the UA-induced current across BLM and the UA-mediated calcium extraction, but also the uncoupling activity of UA in mitochondria and the inhibiting effect of UA on the growth of Bacillus subtilis. The ability of UA to cause dissipation of membrane potential in isolated liver mitochondria and bacterial cells was shown here for the first time. In view of the data obtained, the protonophoric activity of UA is considered to make a significant contribution to its antibacterial action.
- Published
- 2019
38. Carborane derivatives of 1,2,3-triazole depolarize mitochondria by transferring protons through the lipid part of membranes
- Author
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Alexei V. Shunaev, Yuri N. Antonenko, Valentina A. Ol'shevskaya, Alexander A. Shtil, Tatyana I. Rokitskaya, Victor V. Tatarskiy, Anton V. Makarenkov, and Khailova Ls
- Subjects
Boron Compounds ,Protonophore ,Biophysics ,Triazole ,Mitochondria, Liver ,01 natural sciences ,Biochemistry ,Membrane Lipids ,03 medical and health sciences ,chemistry.chemical_compound ,Animals ,Humans ,030304 developmental biology ,Membrane Potential, Mitochondrial ,Membrane potential ,0303 health sciences ,Liposome ,Ion Transport ,Uncoupling Agents ,010405 organic chemistry ,Biological membrane ,Biological activity ,Cell Biology ,Triazoles ,HCT116 Cells ,Mitochondria ,Rats ,0104 chemical sciences ,Membrane ,chemistry ,Mitochondrial Membranes ,Carborane ,Protons ,K562 Cells - Abstract
Boron containing polyhedra (carboranes) are three-dimensional delocalized aromatic systems. These structures have been shown to transport protons through lipid membranes and mitochondria. Conjugation of carboranes to various organic moieties is aimed at obtaining biologically active compounds with novel properties. Taking advantage of 1,2,3-triazoles as the scaffolds valuable in medicinal chemistry, we synthesized 1-(o-carboranylmethyl)-4-pentyl-1,2,3-triazole (c-triazole) and 1-(o-carboranylmethyl)-4-pentyl-1,2,3-triazolium iodide (c-triazolium). Both compounds interacted with model lipid membranes and exhibited a proton carrying activity in planar bilayers and liposomes in a concentration- and pH-dependent manner. Importantly, mechanisms of the protonophoric activity differed; namely, protonation-deprotonation reactions of the triazole and the o-carborane moieties were involved in the transport cycles of c-triazole and c-triazolium, respectively. At micromolar concentrations, c-triazole and c-triazolium stimulated respiration of isolated rat liver mitochondria and depolarized their membrane potential, with c-triazole being more potent. In living K562 (human chronic myelogenous leukemia) cells, both c-triazolium and c-triazole altered the mitochondrial membrane potential as determined by a decreased intracellular accumulation of the potential-dependent dye tetramethylrhodamine ethyl ester. Finally, cell viability testing demonstrated a cytotoxic potency of c-triazolium and, to a lesser extent, of c-triazole against K562 cells, whereas non-malignant fibroblasts were much less sensitive. In all tests, the reference boron-free benzyl-4-pentyl-1,2,3-triazole showed little-to-no effects. These results demonstrated that carboranyltriazoles carry protons across biological membranes, a property potentially important in anticancer drug design.
- Published
- 2019
39. Role of mitochondrial outer membrane in the uncoupling activity of N-terminally glutamate-substituted gramicidin A
- Author
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Sergey I. Kovalchuk, Tatyana I. Rokitskaya, Khailova Ls, Alexandra I. Sorochkina, Еlena А. Kotova, and Yuri N. Antonenko
- Subjects
Male ,0301 basic medicine ,Glutamine ,Membrane lipids ,Biophysics ,Mitochondria, Liver ,01 natural sciences ,Biochemistry ,Membrane Lipids ,03 medical and health sciences ,chemistry.chemical_compound ,Glutamates ,Protein Domains ,Animals ,Inner mitochondrial membrane ,Ions ,Membrane Potential, Mitochondrial ,Membrane potential ,Liposome ,010405 organic chemistry ,Chemistry ,Gramicidin ,Membrane Proteins ,Valine ,Biological membrane ,Cell Biology ,Hydrogen-Ion Concentration ,Membrane transport ,Lipids ,Rats ,0104 chemical sciences ,030104 developmental biology ,Membrane ,Liposomes ,Mitochondrial Membranes - Abstract
Of a series of gramicidin A (gA) derivatives, we have earlier found the peptide [Glu1]gA exhibiting very low toxicity toward mammalian cells, although dissipating mitochondrial membrane potential with almost the same efficiency as gA. Substitution of glutamate for valine at position 1 of the gA amino acid sequence, which is supposed to interfere with the formation of ion-conducting gA channels via head-to-head dimerization, reduces both channel-forming potency of the peptide in planar lipid bilayer membranes and its photonophoric activity in unilamellar liposomes. Here, we compared [Glu1]gA and gA abilities to cause depolarization of the inner mitochondrial membrane in mitochondria and mitoplasts, the latter lacking the outer mitochondrial membrane. Importantly, much less gA was needed to decrease the membrane potential in mitoplasts than in mitochondria, whereas the depolarizing potency of [Glu1]gA was nearly the same in these systems. Moreover, in multilamellar liposomes, [Glu1]gA exhibited more pronounced protonophoric activity than gA, in contrast to the data for unilamellar liposomes. These results allowed us to conclude that [Glu1]gA has a much higher permeability between adjacent lipid membranes than gA. Therefore, the fraction of peptide molecules, reaching the inner mitochondrial membrane upon the addition to cells, is much higher for [Glu1]gA compared to gА. Under these conditions, the decreased cytotoxicity of [Glu1]gA could be associated with its low efficiency as a channel-former dissipating potassium and sodium ion gradients across plasma membrane. The present study highlighted the role of the ability to permeate among various biological membranes for intracellular efficiency of ionophores.
- Published
- 2019
40. Effect of methyl and halogen substituents on the transmembrane movement of lipophilic ions
- Author
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Tatyana I. Rokitskaya, Galina A. Korshunova, Victor B. Luzhkov, Vadim N. Tashlitsky, and Yuri N. Antonenko
- Subjects
Lipid Bilayers ,Tetraphenylborate ,Substituent ,General Physics and Astronomy ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Ion ,chemistry.chemical_compound ,Halogens ,Organophosphorus Compounds ,Electricity ,Computational chemistry ,Physical and Theoretical Chemistry ,Lipid bilayer ,Density Functional Theory ,Octane ,Ions ,Solvation ,Water ,Halogenation ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Solvents ,Density functional theory ,0210 nano-technology ,Hydrophobic and Hydrophilic Interactions - Abstract
Penetrating cations are widely used for the design of bioactive mitochondria-targeted compounds. The introduction of various substituents into the phenyl rings of dodecyltriphenylphosphonium and the measurement of the flip-flop of the synthesized cations by the current relaxation method revealed that methyl groups accelerated significantly the cation penetration through the lipid membrane, depending on the number of groups introduced. However, halogenation slowed down the penetration of the analogues. This result is strictly opposite to the flip-flop acceleration observed for halogenated tetraphenylborate anions. Density functional theory and the polarizable continuum solvent model were used to calculate the solvation energies of methyltriphenylphosphonium and methyltriphenylborate analogues. A good agreement was demonstrated between the difference in the free energy of ion solvation in water and octane and the absolute value of the central free energy barrier estimated from experimental data. Our results reveal that increasing the size of the lipophilic ion can lead to both acceleration and deceleration of the transmembrane flip-flop rate depending on the substituent and sign of the ion. This finding also emphasizes the different nature of ion-water interactions for structurally similar substituted hydrophobic anions and cations.
- Published
- 2019
41. Lysine 72 substitutions differently affect lipid membrane permeabilizing and proapoptotic activities of horse heart cytochrome c
- Author
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Dmitry A. Dolgikh, Ivan D. Gusev, Alexander M. Firsov, Yuri N. Antonenko, Rita V. Chertkova, Mikhail P. Kirpichnikov, and Elena A. Kotova
- Subjects
0301 basic medicine ,Time Factors ,Lysine ,Lipid Bilayers ,Biophysics ,Apoptosis ,environment and public health ,Biochemistry ,Permeability ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cardiolipin ,Animals ,Horses ,Lipid bilayer ,Molecular Biology ,Liposome ,biology ,Cytochrome c ,Myocardium ,Cytochromes c ,Cell Biology ,Calcein ,enzymes and coenzymes (carbohydrates) ,030104 developmental biology ,Membrane ,chemistry ,Amino Acid Substitution ,030220 oncology & carcinogenesis ,embryonic structures ,Liposomes ,cardiovascular system ,biology.protein ,Peroxidase ,Protein Binding - Abstract
Peroxidase activity of cytochrome c (cyt c)/cardiolipin (CL) complex is supposed to be involved in the initiation of apoptosis via peroxidative induction of mitochondrial membrane permeabilization. As cyt c binding to CL-containing membranes is at least partially associated with electrostatic protein/lipid interaction, we screened single-point mutants of horse heart cyt c with various substitutions of lysine at position 72, considered to play a significant role in both the binding and peroxidase activity of the protein. Contrary to expectations, K72A, K72R and K72L substitutions exerted slight effects on both the cyt c binding to CL-containing liposomal membranes and the cyt c/H2O2-induced calcein leakage from liposomes, used here as a membrane permeabilization assay. Both the binding and permeabilization were decreased to various extents, but not significantly, in the case of K72E and K72N mutants. A drastic difference was found between the sequence of the permeabilizing activities of the cyt c variants and the previously described order of their proapoptotic activities (Chertkova et al., 2008).
- Published
- 2021
42. Bicarbonate suppresses mitochondrial membrane depolarization induced by conventional uncouplers
- Author
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Yuri N. Antonenko, Elena A. Kotova, Khailova Ls, G.Y. Lomakina, and Tatyana V. Vygodina
- Subjects
0301 basic medicine ,Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone ,Carbonyl Cyanide m-Chlorophenyl Hydrazone ,Protonophore ,ATPase ,Bicarbonate ,Biophysics ,chemical and pharmacologic phenomena ,Mitochondria, Liver ,Mitochondrion ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Adenosine Triphosphate ,Cytochrome c oxidase ,Animals ,education ,Molecular Biology ,Membrane potential ,Membrane Potential, Mitochondrial ,education.field_of_study ,biology ,Chemistry ,Uncoupling Agents ,organic chemicals ,Depolarization ,Cell Biology ,Soluble adenylyl cyclase ,Rats ,Bicarbonates ,030104 developmental biology ,030220 oncology & carcinogenesis ,Mitochondrial Membranes ,biology.protein ,2,4-Dinitrophenol - Abstract
Bicarbonate has been known to modulate activities of various mitochondrial enzymes such as ATPase and soluble adenylyl cyclase. Here, we found that the ability of conventional protonophoric uncouplers, such as 2,4-dinitrophenol (DNP), carbonylcyanide p-trifluoromethoxyphenylhydrazone (FCCP) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP), but not that of the new popular uncoupler BAM15, to decrease mitochondrial membrane potential was significantly diminished in the presence of millimolar concentrations of bicarbonate. Thus, the depolarizing activity of DNP and FCCP in mitochondria could be sensitive to the local concentration of bicarbonate in cells and tissues. However, bicarbonate could not restore the ATP synthesis suppressed by DNP or CCCP in mitochondria. Bicarbonate neither altered the depolarizing action of DNP and FCCP on proteoliposomes with reconstituted cytochrome c oxidase, nor affected the protonophoric activity of DNP and FCCP in artificial lipid membranes as measured with pyranine-loaded liposomes, thereby showing that the bicarbonate-induced reversal of the depolarizing action of DNP and FCCP on mitochondria did not result from direct interaction of bicarbonate with the uncouplers.
- Published
- 2020
43. Lipophilic ion aromaticity is not important for permeability across lipid membranes
- Author
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Vadim N. Tashlitsky, Elena A. Kotova, Yuri N. Antonenko, Victor B. Luzhkov, Tatyana I. Rokitskaya, Galina A. Korshunova, Ekaterina V. Aleksandrova, and Roman S. Kirsanov
- Subjects
Lipid Bilayers ,Biophysics ,Fluorescence correlation spectroscopy ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Permeability ,Membrane Lipids ,Onium Compounds ,Organophosphorus Compounds ,Lipid bilayer ,Alkyl ,Membrane potential ,chemistry.chemical_classification ,Chemistry ,Bilayer ,Trityl Compounds ,Cell Biology ,Permeation ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Membrane ,Permeability (electromagnetism) ,0210 nano-technology - Abstract
To clarify the contribution of charge delocalization in a lipophilic ion to the efficacy of its permeation through a lipid membrane, we compared the behavior of alkyl derivatives of triphenylphosphonium, tricyclohexylphosphonium and trihexylphosphonium both in natural and artificial membranes. Exploring accumulation of the lipophilic cations in response to inside-negative membrane potential generation in mitochondria by using an ion-selective electrode revealed similar mitochondrial uptake of butyltricyclohexylphosphonium (C4TCHP) and butyltriphenylphosphonium (C4TPP). Fluorescence correlation spectroscopy also demonstrated similar membrane potential-dependent accumulation of fluorescein derivatives of tricyclohexyldecylphosphonium and decyltriphenylphosphonium in mitochondria. The rate constant of lipophilic cation translocation across the bilayer lipid membrane (BLM), measured by the current relaxation method, moderately increased in the following sequence: trihexyltetradecylphosphonium ([P6,6,6,14])
- Published
- 2020
44. MITONBD - A NEW FLUORESCENT MITOCHONDRIAL UNCOUPLER WITH HIGH ANTIBACTERIAL ACTIVITY
- Author
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Tatyana I. Rokitskaya, Khailova Ls, Elena A. Kotova, Yuri N. Antonenko, I.R. Iaubasarova, and Galina A. Korshunova
- Subjects
Biochemistry ,Chemistry ,Antibacterial activity ,Fluorescence - Published
- 2020
45. NEW UNCOUPLERS OF OXIDATIVE PHOSPHORYLATION: BAM15, PYRROLOMYCIN AND USNIC ACID
- Author
-
Yuri N. Antonenko
- Subjects
chemistry.chemical_compound ,Biochemistry ,Chemistry ,Usnic acid ,Oxidative phosphorylation - Published
- 2020
46. Fluorescein Derivatives as Antibacterial Agents Acting via Membrane Depolarization
- Author
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Stepan S. Denisov, Konstantin G. Lyamzaev, Marina V. Karakozova, Yuri N. Antonenko, Pavel A. Nazarov, Elena A. Kotova, Khailova Ls, Konstantin A. Lukyanov, Galina A. Korshunova, Roman S. Kirsanov, Biochemie, and RS: Carim - B01 Blood proteins & engineering
- Subjects
0301 basic medicine ,EFFLUX ,antibacterial agent ,lcsh:QR1-502 ,Fluorescence correlation spectroscopy ,Mitochondria, Liver ,Bacillus subtilis ,Biochemistry ,lcsh:Microbiology ,Oxidative Phosphorylation ,Article ,Russia ,BACILLUS-SUBTILIS ,03 medical and health sciences ,chemistry.chemical_compound ,bacterial membrane depolarization ,OXIDATIVE-PHOSPHORYLATION ,Fluorescence microscope ,Animals ,fluorescein derivative ,Phosphonium ,Fluorescein ,PROBE ,Molecular Biology ,Antibacterial agent ,Membrane potential ,fluorescent uncoupler ,030102 biochemistry & molecular biology ,biology ,PLATFORM ,Depolarization ,UNCOUPLERS ,biology.organism_classification ,Anti-Bacterial Agents ,Rats ,mitochondria ,030104 developmental biology ,Bacterial Outer Membrane ,Spectrometry, Fluorescence ,chemistry ,TRIPHENYLPHOSPHONIUM ,Biophysics ,CATIONS ,membrane potential - Abstract
Appending a lipophylic alkyl chain by ester bond to fluorescein has been previously shown to convert this popular dye into an effective protonophoric uncoupler of oxidative phosphorylation in mitochondria, exhibiting neuro- and nephroprotective effects in murine models. In line with this finding, we here report data on the pronounced depolarizing effect of a series of fluorescein decyl esters on bacterial cells. The binding of the fluorescein derivatives to Bacillus subtilis cells was monitored by fluorescence microscopy and fluorescence correlation spectroscopy (FCS). FCS revealed the energy-dependent accumulation of the fluorescein esters with decyl(triphenyl)- and decyl(tri-p-tolyl)phosphonium cations in the bacterial cells. The latter compound proved to be the most potent in suppressing B. subtilis growth.
- Published
- 2020
47. Membrane Binding of Neuronal Calcium Sensor-1: Highly Specific Interaction with Phosphatidylinositol-3-Phosphate
- Author
-
Arthur O. Zalevsky, Andrey A. Zamyatnin, Ekaterina L. Nemashkalova, Viktoriia E. Baksheeva, Natalia K. Tikhomirova, Alexander M. Firsov, Dmitry V. Zinchenko, Vasily I. Vladimirov, S.E. Permyakov, Yuri N. Antonenko, Evgeni Yu. Zernii, and Pavel P. Philippov
- Subjects
0301 basic medicine ,Light ,lcsh:QR1-502 ,PI3P ,Ligands ,Hippocampus ,Myristic Acid ,Biochemistry ,lcsh:Microbiology ,neuronal calcium sensor-1 ,phosphatidylinositol-3-phosphate ,chemistry.chemical_compound ,0302 clinical medicine ,Phosphatidylinositol Phosphates ,myristoyl group ,Magnesium ,Neurons ,NCS-1 ,biology ,Temperature ,Phosphatidylserine ,phosphoinositides ,Molecular Docking Simulation ,Membrane ,lipids (amino acids, peptides, and proteins) ,Signal transduction ,Protein Binding ,Signal Transduction ,Neuronal Calcium-Sensor Proteins ,Static Electricity ,Phospholipid ,N-terminal myristoylation ,Article ,03 medical and health sciences ,Protein Domains ,Humans ,Phosphatidylinositol ,membrane binding ,Molecular Biology ,Myristoylation ,Binding Sites ,Lysine ,Phosphatidylinositol 3-phosphate ,Neuropeptides ,Hydrogen Bonding ,phospholipid-binding proteins ,Spectrometry, Fluorescence ,030104 developmental biology ,Neuronal calcium sensor-1 ,chemistry ,neuronal calcium sensors ,Liposomes ,Mutation ,Biophysics ,biology.protein ,Calcium ,030217 neurology & neurosurgery - Abstract
Neuronal calcium sensors are a family of N-terminally myristoylated membrane-binding proteins possessing a different intracellular localization and thereby targeting unique signaling partner(s). Apart from the myristoyl group, the membrane attachment of these proteins may be modulated by their N-terminal positively charged residues responsible for specific recognition of the membrane components. Here, we examined the interaction of neuronal calcium sensor-1 (NCS-1) with natural membranes of different lipid composition as well as individual phospholipids in form of multilamellar liposomes or immobilized monolayers and characterized the role of myristoyl group and N-terminal lysine residues in membrane binding and phospholipid preference of the protein. NCS-1 binds to photoreceptor and hippocampal membranes in a Ca2+-independent manner and the binding is attenuated in the absence of myristoyl group. Meanwhile, the interaction with photoreceptor membranes is less dependent on myristoylation and more sensitive to replacement of K3, K7, and/or K9 of NCS-1 by glutamic acid, reflecting affinity of the protein to negatively charged phospholipids. Consistently, among the major phospholipids, NCS-1 preferentially interacts with phosphatidylserine and phosphatidylinositol with micromolar affinity and the interaction with the former is inhibited upon mutating of N-terminal lysines of the protein. Remarkably, NCS-1 demonstrates pronounced specific binding to phosphoinositides with high preference for phosphatidylinositol-3-phosphate. The binding does not depend on myristoylation and, unexpectedly, is not sensitive to the charge inversion mutations. Instead, phosphatidylinositol-3-phosphate can be recognized by a specific site located in the N-terminal region of the protein. These data provide important novel insights into the general mechanism of membrane binding of NCS-1 and its targeting to specific phospholipids ensuring involvement of the protein in phosphoinositide-regulated signaling pathways.
- Published
- 2020
- Full Text
- View/download PDF
48. Viral rhodopsins 1 are an unique family of light-gated cation channels
- Author
-
R. Astashkin, G. A. Armeev, Natalia Yutin, Andreas Offenhäusser, Ekaterina Savelyeva, Kirill Kovalev, Igor Chizhov, Dmitrii Zabelskii, Francisco Rodriguez-Valera, Ernst Bamberg, Alexander Popov, Vladan Rankovic, Maksim Rulev, Dmitry Bratanov, Valentin Gordeliy, Alexey Alekseev, Michel Vivaudou, D V Soloviov, Riccardo Rosselli, Taras Balandin, Tatiana I. Rokitskaya, Eugene V. Koonin, Georg Büldt, Svetlana Vaganova, Ana-Sofia Eria-Oliveira, Yuri N. Antonenko, Tobias Moser, Mikhail P. Kirpichnikov, A. V. Rogachev, Thomas Mager, Dieter Willbold, Elizaveta Podolyak, Dmytro Volkov, Konstantin V. Shaitan, Institute of Biological Information Processing [Jülich] (IBI-7), Institut de biologie structurale (IBS - UMR 5075), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes (UGA), Institute for Auditory Neuroscience and InnerEarLab, Research Center for Molecular Mechanisms of Aging and Age-related Diseases, Moscow, Hannover Medical School [Hannover] (MHH), National Center for Biotechnology Information (NCBI), European Synchrotron Radiation Facility (ESRF), Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University (MSU), Max-Planck-Institut für Biophysik - Max Planck Institute of Biophysics (MPIBP), Max-Planck-Gesellschaft, Departamento de Producción Vegetal y Microbiología, Universidad Miguel Hernández [Elche] (UMH), Lomonosov Moscow State University, Biological Faculty, N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences [Moscow] (RAS), InnerEarLab, Department of Otolaryngology and Center for Molecular Physiology of the Brain-Georg-August-University = Georg-August-Universität Göttingen, National Center for Biotechnology Information, National Institutes of Health, Department of Health and Human Services, Bethesda, Md, National Institutes of Health [Bethesda] (NIH), ANR-17-EURE-0003,CBH-EUR-GS,CBH-EUR-GS(2017), ANR-19-CE11-0026,Viral_Rhodopsins,Rhodopsines virales: Structure, Fonction, et Nouveaux Outils pour l'Optogénétique(2019), and Department of Otolaryngology and Center for Molecular Physiology of the Brain-University of Göttingen - Georg-August-Universität Göttingen
- Subjects
0301 basic medicine ,genetic structures ,Light ,Protein Conformation ,General Physics and Astronomy ,Channelrhodopsin ,0302 clinical medicine ,Protein structure ,X-Ray Diffraction ,Phototaxis ,lcsh:Science ,Cells, Cultured ,Phylogeny ,Neurons ,Multidisciplinary ,biology ,[SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM] ,Chemistry ,Cell biology ,Rhodopsin ,ddc:500 ,Ion Channel Gating ,Science ,Optogenetics ,Nucleocytoplasmic large DNA viruses ,Virus-host interactions ,Article ,General Biochemistry, Genetics and Molecular Biology ,Structure-Activity Relationship ,Viral Proteins ,03 medical and health sciences ,Channelrhodopsins ,Phylogenetics ,Cations ,Animals ,Humans ,14. Life underwater ,Rats, Wistar ,Ion transport ,HEK 293 cells ,fungi ,General Chemistry ,biology.organism_classification ,HEK293 Cells ,030104 developmental biology ,Phytoplankton ,biology.protein ,lcsh:Q ,Calcium ,sense organs ,030217 neurology & neurosurgery - Abstract
Phytoplankton is the base of the marine food chain as well as oxygen and carbon cycles and thus plays a global role in climate and ecology. Nucleocytoplasmic Large DNA Viruses that infect phytoplankton organisms and regulate the phytoplankton dynamics encompass genes of rhodopsins of two distinct families. Here, we present a functional and structural characterization of two proteins of viral rhodopsin group 1, OLPVR1 and VirChR1. Functional analysis of VirChR1 shows that it is a highly selective, Na+/K+-conducting channel and, in contrast to known cation channelrhodopsins, it is impermeable to Ca2+ ions. We show that, upon illumination, VirChR1 is able to drive neural firing. The 1.4 Å resolution structure of OLPVR1 reveals remarkable differences from the known channelrhodopsins and a unique ion-conducting pathway. Thus, viral rhodopsins 1 represent a unique, large group of light-gated channels (viral channelrhodopsins, VirChR1s). In nature, VirChR1s likely mediate phototaxis of algae enhancing the host anabolic processes to support virus reproduction, and therefore, might play a major role in global phytoplankton dynamics. Moreover, VirChR1s have unique potential for optogenetics as they lack possibly noxious Ca2+ permeability., Nucleocytoplasmic Large DNA Viruses (NCLDV) that infect algae encode two distinct families of microbial rhodopsins. Here, the authors characterise two proteins form the viral rhodopsin group 1 OLPVR1 and VirChR1, present the 1.4 Å crystal structure of OLPVR1 and show that viral rhodopsins 1 are light-gated cation channels.
- Published
- 2020
- Full Text
- View/download PDF
49. Membrane Elastic Deformations Modulate Gramicidin A Transbilayer Dimerization and Lateral Clustering
- Author
-
Yuri N. Antonenko, Timur R. Galimzyanov, Elena A. Kotova, Oleg V. Kondrashov, Sergey A. Akimov, and Konstantin V. Pavlov
- Subjects
0301 basic medicine ,Materials science ,Dimer ,Lipid Bilayers ,Biophysics ,Quantitative Biology::Subcellular Processes ,03 medical and health sciences ,chemistry.chemical_compound ,Monolayer ,Protein Structure, Quaternary ,Lipid bilayer ,Probability ,Quantitative Biology::Biomolecules ,Physics::Biological Physics ,Membranes ,030102 biochemistry & molecular biology ,Bilayer ,Cell Membrane ,Gramicidin ,Elastic energy ,Interaction energy ,Elasticity (physics) ,Elasticity ,Condensed Matter::Soft Condensed Matter ,030104 developmental biology ,Membrane ,chemistry ,Chemical physics ,Protein Multimerization - Abstract
Gramicidin A (gA) is a short β-helical peptide known to form conducting channels in lipid membranes because of transbilayer dimerization. The gA conducting dimer, being shorter than the lipid bilayer thickness, deforms the membrane in its vicinity, and the bilayer elastic energy contributes to the gA dimer formation energy. Likewise, membrane incorporation of a gA monomer, which is shorter than the lipid monolayer thickness, creates a void, thereby forcing surrounding lipid molecules to tilt to fill it. The energy of membrane deformation was calculated in the framework of the continuum elasticity theory, taking into account splay, tilt, lateral stretching/compression, Gaussian splay deformations, and external membrane tension. We obtained the interaction energy profiles for two gA monomers located either in the same or in the opposite monolayers. The profiles demonstrated the long-range attraction and short-range repulsion behavior of the monomers resulting from the membrane deformation. Analysis of the profile features revealed conditions under which clusters of gA monomers would not dissipate because of diffusion. The calculated dependence of the dimer formation and decay energy barriers on the membrane elastic properties was in good agreement with the available experimental data and suggested an explanation for a hitherto contentious phenomenon.
- Published
- 2018
50. Photodynamic damage to erythrocytes and liposomes sensitized by chlorophyll a derivatives
- Author
-
Yuri N. Antonenko, I. S. Khudyaeva, Elena A. Kotova, Alexander M. Firsov, Dmitry V. Belykh, Oksana G. Shevchenko, and S. N. Plyusnina
- Subjects
0301 basic medicine ,030103 biophysics ,Chlorophyll a ,Liposome ,010405 organic chemistry ,Sulforhodamine B ,General Chemistry ,medicine.disease ,01 natural sciences ,Hemolysis ,0104 chemical sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Membrane ,chemistry ,medicine ,Biophysics ,Hemoglobin ,Lipid bilayer ,Photodegradation - Abstract
A comparative study of photohemolysis of erythrocytes and photodamage to liposomes sensitized by the chlorophyll a derivatives is reported. The photomodification of liposomes was assessed by the degree of leakage of sulforhodamine B, whereas hemolysis was measured by the release of hemoglobin. A statistically significant positive correlation between the degree of photohemolysis of erythrocytes and the degree of photodamage to liposomes was found. The correlation observed suggests that the photoinduced loss of lipid bilayer integrity is the main mechanism of photodegradation of erythrocyte membranes in the case of the photosensitizers studied.
- Published
- 2018
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