Journal articles: 'Membrane transport systems'

1

Stephan, Wolfgang. "Complex membrane transport systems." Biophysical Chemistry 21, no. 1 (January 1985): 41–55. http://dx.doi.org/10.1016/0301-4622(85)85005-5.

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Briskin, Donald P. "Membranes and Transport Systems in Plants: An Overview." Weed Science 42, no. 2 (June 1994): 255–62. http://dx.doi.org/10.1017/s0043174500080371.

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Membranes define the outer boundary of the living protoplast and the internal compartmentation of plant cells. From a structural point of view, membranes consist of a lipid bilayer and proteins essential for functions such as solute transport, signal transduction, and numerous metabolic reactions. While membranes can represent a significant barrier to the free movement of many solutes, those with sufficient lipid solubility may move across membranes by dissolving into the lipid bilayer. However, selective membrane transport is generally observed for hydrophilic solutes such as mineral nutrients and cell metabolites. Such selective transport requires an input of metabolic energy, and in plants this occurs via the production of proton electrochemical gradients across the membrane by substrate- (ex. ATP, PPi) driven proton pumps. Selective solute transport is then mediated by membrane-associated secondary transport systems which utilize the proton electrochemical gradient to drive the transport process. This review of membrane structure and transport system function provides a background for a further examination of herbicide interactions with plant membranes.

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Hoffman, Joseph F. "Modulation of Membrane Transport Systems." Annual Review of Physiology 50, no. 1 (October 1988): 205. http://dx.doi.org/10.1146/annurev.ph.50.030188.001225.

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Garcia-Sa´inz, J. Adolfo. "Cell and membrane transport systems." Trends in Pharmacological Sciences 8, no. 9 (September 1987): 364. http://dx.doi.org/10.1016/0165-6147(87)90151-9.

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Marino, Angela, Silvia Dossena, Grazia Tamma, and Sandra Donnini. "Oxidative Stress and Membrane Transport Systems." Oxidative Medicine and Cellular Longevity 2018 (June 13, 2018): 1–2. http://dx.doi.org/10.1155/2018/9625213.

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Higa, Mitsuru. "Ionic Transport across Charged Membranes in Multi-component Ionic Systems." membrane 23, no. 6 (1998): 300–307. http://dx.doi.org/10.5360/membrane.23.300.

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7

Bastlein, C., and G. Burckhardt. "Sensitivity of rat renal luminal and contraluminal sulfate transport systems to DIDS." American Journal of Physiology-Renal Physiology 250, no. 2 (February 1, 1986): F226—F234. http://dx.doi.org/10.1152/ajprenal.1986.250.2.f226.

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4,4'-diisothiocyanostilbene-2,2'-disulfonic acid (DIDS) was tested as an inhibitor of the sulfate transport systems in rat renal brush border and basolateral membrane vesicles. Na+-driven sulfate uptake into brush border membrane vesicles was half-maximally inhibited at 350 microM DIDS. Proton gradient-driven sulfate uptake into basolateral membrane vesicles was competitively inhibited by DIDS with a Ki of 2.4 microM. The Km for delta pH-driven sulfate uptake was 5.4 microM. The different affinities of the sulfate transport systems for DIDS correlated with different substrate specificities. The luminal transport system accepted a smaller range of anions than the contraluminal system and did not operate as a Na+-independent anion exchanger. After treatment of basolateral membrane vesicles with 50 microM DIDS at pH 8.4 for 30 min, an irreversible inhibition of sulfate uptake was observed. With brush border membranes, only a small irreversible inhibition was obtained. Lack of inhibition after treatment of basolateral membranes with DIDS at pH 6.4 indicated that DIDS reacted with deprotonated amino groups of the transport protein. Sulfate was protected from the irreversible inhibition by DIDS. Sodium-driven uptake of L-glutamate and methylsuccinate into basolateral membrane vesicles was not irreversibly inhibited by DIDS, indicating a specific action of DIDS on the contraluminal sulfate transport system. Irreversible and substrate-protectable inhibition of sulfate transport render DIDS suitable for future affinity labeling studies on the sulfate transport system in basolateral membranes.

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Nikonenko, Victor, Andrey Nebavsky, Semyon Mareev, Anna Kovalenko, Mahamet Urtenov, and Gerald Pourcelly. "Modelling of Ion Transport in Electromembrane Systems: Impacts of Membrane Bulk and Surface Heterogeneity." Applied Sciences 9, no. 1 (December 21, 2018): 25. http://dx.doi.org/10.3390/app9010025.

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Artificial charged membranes, similar to the biological membranes, are self-assembled nanostructured materials constructed from macromolecules. The mutual interactions of parts of macromolecules leads to phase separation and appearance of microheterogeneities within the membrane bulk. On the other hand, these interactions also cause spontaneous microheterogeneity on the membrane surface, to which macroheterogeneous structures can be added at the stage of membrane fabrication. Membrane bulk and surface heterogeneity affect essentially the properties and membrane performance in the applications in the field of separation (water desalination, salt concentration, food processing and other), energy production (fuel cells, reverse electrodialysis), chlorine-alkaline electrolysis, medicine and other. We review the models describing ion transport in ion-exchange membranes and electromembrane systems with an emphasis on the role of micro- and macroheterogeneities in and on the membranes. Irreversible thermodynamics approach, “solution-diffusion” and “pore-flow” models, the multiphase models built within the effective-medium approach are examined as the tools for describing ion transport in the membranes. 2D and 3D models involving or not convective transport in electrodialysis cells are presented and analysed. Some examples are given when specially designed surface heterogeneity on the membrane surface results in enhancement of ion transport in intensive current electrodialysis.

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Hoeltzli, S. D., and C. H. Smith. "Alanine transport systems in isolated basal plasma membrane of human placenta." American Journal of Physiology-Cell Physiology 256, no. 3 (March 1, 1989): C630—C637. http://dx.doi.org/10.1152/ajpcell.1989.256.3.c630.

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Concentrative transfer of amino acids from mother to fetus is affected by transport across both microvillous (maternal-facing) and basal (fetal-facing) plasma membranes of the human placental syncytiotrophoblast. Isolated basal plasma membrane vesicles were used to elucidate transport systems for neutral amino acids across this membrane. The concentration dependence and inhibition of zero-trans-alanine uptake were studied and four pathways for alanine uptake were defined as follows: 1) a sodium-dependent system shared by methylaminoisobutyric acid, which has the characteristics of an A system; 2) a sodium-dependent system resistant to inhibition by methylaminoisobutyric acid, which has the characteristics of an ASC system; 3) a sodium-independent system which may resemble an L system; 4) nonsaturable uptake. The microvillous membrane of the syncytiotrophoblast possesses systems similar to 1 and 3, but system 2 is unique to the basal plasma membrane. Active and passive transport of amino acids across both microvillous and basal plasma membranes may contribute to trophoblast amino acid uptake and nutrition and to the transfer of amino acids to the fetus.

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10

Malandro, M. S., M. J. Beveridge, M. S. Kilberg, and D. A. Novak. "Ontogeny of cationic amino acid transport systems in rat placenta." American Journal of Physiology-Cell Physiology 267, no. 3 (September 1, 1994): C804—C811. http://dx.doi.org/10.1152/ajpcell.1994.267.3.c804.

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Gestational regulation of the placental transfer of amino acids from maternal to fetal circulations is essential for the proper development of the fetus. The cationic amino acid transport systems of the microvillous (maternal facing) and basal (fetal facing) membranes of the rat placental syncytiotrophoblast were examined. Inhibition analysis documented the presence of three kinetically distinct cationic amino acid transport mechanisms: a single Na(+)-dependent mechanism in the microvillous membrane, which increased in activity from 14 to 20 days gestation but was absent from the basal membrane throughout the entire gestational period (system Bo,+), and two Na(+)-independent transport systems in both membrane domains, one that is completely inhibited by leucine, which increased in activity in both the microvillous and basal membrane domains, and the other that is leucine insensitive, which remained fairly constant in the basal membrane and increased throughout gestation in the microvillous membrane (system y1+). Northern analysis with the system y1+ cDNA revealed a specific band of approximately 7.4-7.9 kb, which increased with increasing gestational age.

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Field, Mark C., and Mark Carrington. "Intracellular Membrane Transport Systems in Trypanosoma brucei." Traffic 5, no. 12 (October 5, 2004): 905–13. http://dx.doi.org/10.1111/j.1600-0854.2004.00234.x.

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12

Konishi, Hiroaki, Mikihiro Fujiya, and Yutaka Kohgo. "Host-microbe interactions via membrane transport systems." Environmental Microbiology 17, no. 4 (December 17, 2014): 931–37. http://dx.doi.org/10.1111/1462-2920.12632.

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13

Beliveau, R., and M. Potier. "The Radiation Inactivation of Membrane Transport Systems." Physiology 4, no. 4 (August 1, 1989): 134–38. http://dx.doi.org/10.1152/physiologyonline.1989.4.4.134.

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Relatively few methods are available to estimate the size of proteins in biological membranes. The radiation inactivation method does not require purified preparation and allows the study in situ of physical interaction between protein subunits, providing crucial information about the structure-function relationship of protein molecules.

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14

Findlay, John B. C. "Structure and function in membrane transport systems." Current Opinion in Structural Biology 1, no. 5 (October 1991): 804–10. http://dx.doi.org/10.1016/0959-440x(91)90182-s.

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15

Featherstone, Carol. "Perforated cell systems to study membrane transport." Trends in Biochemical Sciences 13, no. 8 (August 1988): 284–86. http://dx.doi.org/10.1016/0968-0004(88)90118-1.

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16

Nikonenko, Victor, and Natalia Pismenskaya. "Ion and Molecule Transport in Membrane Systems." International Journal of Molecular Sciences 22, no. 7 (March 30, 2021): 3556. http://dx.doi.org/10.3390/ijms22073556.

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17

Kirk, Kiaran. "Membrane Transport in the Malaria-Infected Erythrocyte." Physiological Reviews 81, no. 2 (April 1, 2001): 495–537. http://dx.doi.org/10.1152/physrev.2001.81.2.495.

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The malaria parasite is a unicellular eukaryotic organism which, during the course of its complex life cycle, invades the red blood cells of its vertebrate host. As it grows and multiplies within its host blood cell, the parasite modifies the membrane permeability and cytosolic composition of the host cell. The intracellular parasite is enclosed within a so-called parasitophorous vacuolar membrane, tubular extensions of which radiate out into the host cell compartment. Like all eukaryote cells, the parasite has at its surface a plasma membrane, as well as having a variety of internal membrane-bound organelles that perform a range of functions. This review focuses on the transport properties of the different membranes of the malaria-infected erythrocyte, as well as on the role played by the various membrane transport systems in the uptake of solutes from the extracellular medium, the disposal of metabolic wastes, and the origin and maintenance of electrochemical ion gradients. Such systems are of considerable interest from the point of view of antimalarial chemotherapy, both as drug targets in their own right and as routes for targeting cytotoxic agents into the intracellular parasite.

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Alix, Eric, Shaeri Mukherjee, and Craig R. Roy. "Subversion of membrane transport pathways by vacuolar pathogens." Journal of Cell Biology 195, no. 6 (November 28, 2011): 943–52. http://dx.doi.org/10.1083/jcb.201105019.

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Mammalian phagocytes control bacterial infections effectively through phagocytosis, the process by which particles engulfed at the cell surface are transported to lysosomes for destruction. However, intracellular pathogens have evolved mechanisms to avoid this fate. Many bacterial pathogens use specialized secretion systems to deliver proteins into host cells that subvert signaling pathways controlling membrane transport. These bacterial effectors modulate the function of proteins that regulate membrane transport and alter the phospholipid content of membranes. Elucidating the biochemical function of these effectors has provided a greater understanding of how bacteria control membrane transport to create a replicative niche within the host and provided insight into the regulation of membrane transport in eukaryotic cells.

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Kristensen, Mette Birch, Anders Bentien, Michele Tedesco, and Jacopo Catalano. "Counter-ion transport number and membrane potential in working membrane systems." Journal of Colloid and Interface Science 504 (October 2017): 800–813. http://dx.doi.org/10.1016/j.jcis.2017.06.010.

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20

Gawarzewski, Iris, Sander H. J. Smits, Lutz Schmitt, and Joachim Jose. "Structural comparison of the transport units of type V secretion systems." Biological Chemistry 394, no. 11 (November 1, 2013): 1385–98. http://dx.doi.org/10.1515/hsz-2013-0162.

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Abstract Pathogenic gram-negative bacteria have evolved several secretion mechanisms to translocate adhesins, enzymes, toxins, and other virulence factors across the inner and outer membranes. Currently, eight different secretion systems, type I–type VIII (T1SS–T8SS) plus the chaperone-usher (CU) pathway, have been identified, which act in one-step or two-step mechanisms to traverse both membrane barriers. The type V secretion system (T5SS) is dependent first on the Sec translocon within the inner membrane. The periplasmic intermediates are then secreted through aqueous pores formed by β-barrels in the outer membrane. Until now, transport across the outer membrane has not been understood on a molecular level. With respect to special characteristics revealed by crystal structure analysis, bioinformatic and biochemical data, five subgroups of T5SS were defined. Here, we compare the transport moieties of members of four subgroups based on X-ray crystal structures. For the fifth subgroup, which was identified only recently, no structures have thus far been reported. We also discuss different models for the translocation process across the outer membrane with respect to recent findings.

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21

Vertenstein, Mariana, and David Ronis. "Microscopic theory of membrane transport. III. Transport in multiple barrier systems." Journal of Chemical Physics 85, no. 3 (August 1986): 1628–49. http://dx.doi.org/10.1063/1.451205.

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22

Shennan, D. B., and C. A. R. Boyd. "Ion transport by the placenta: a review of membrane transport systems." Biochimica et Biophysica Acta (BBA) - Reviews on Biomembranes 906, no. 3 (October 1987): 437–57. http://dx.doi.org/10.1016/0304-4157(87)90019-0.

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Mullineaux, Conrad W., and Lu-Ning Liu. "Membrane Dynamics in Phototrophic Bacteria." Annual Review of Microbiology 74, no. 1 (September 8, 2020): 633–54. http://dx.doi.org/10.1146/annurev-micro-020518-120134.

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Photosynthetic membranes are typically densely packed with proteins, and this is crucial for their function in efficient trapping of light energy. Despite being crowded with protein, the membranes are fluid systems in which proteins and smaller molecules can diffuse. Fluidity is also crucial for photosynthetic function, as it is essential for biogenesis, electron transport, and protein redistribution for functional regulation. All photosynthetic membranes seem to maintain a delicate balance between crowding, order, and fluidity. How does this work in phototrophic bacteria? In this review, we focus on two types of intensively studied bacterial photosynthetic membranes: the chromatophore membranes of purple bacteria and the thylakoid membranes of cyanobacteria. Both systems are distinct from the plasma membrane, and both have a distinctive protein composition that reflects their specialized roles. Chromatophores are formed from plasma membrane invaginations, while thylakoid membranes appear to be an independent intracellular membrane system. We discuss the techniques that can be applied to study the organization and dynamics of these membrane systems, including electron microscopy techniques, atomic force microscopy, and many variants of fluorescence microscopy. We go on to discuss the insights that havebeen acquired from these techniques, and the role of membrane dynamics in the physiology of photosynthetic membranes. Membrane dynamics on multiple timescales are crucial for membrane function, from electron transport on timescales of microseconds to milliseconds to regulation and biogenesis on timescales of minutes to hours. We emphasize the open questions that remain in the field.

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Barbuti, Roberto, Andrea Maggiolo-Schettini, Paolo Milazzo, and Simone Tini. "P Systems with Transport and Diffusion Membrane Channels." Fundamenta Informaticae 93, no. 1-3 (2009): 17–31. http://dx.doi.org/10.3233/fi-2009-0085.

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25

Nikonenko, V., V. Zabolotsky, C. Larchet, B. Auclair, and G. Pourcelly. "Mathematical description of ion transport in membrane systems." Desalination 147, no. 1-3 (September 2002): 369–74. http://dx.doi.org/10.1016/s0011-9164(02)00611-2.

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26

Li *, Long-Yuan. "Transport of multicomponent ionic solutions in membrane systems." Philosophical Magazine Letters 84, no. 9 (September 2004): 593–99. http://dx.doi.org/10.1080/09500830512331325767.

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27

Lijnen, P., and V. Petrov. "Cell Membrane Cation Transport Systems During Aldosterone Antagonism." Journal of Cardiovascular Pharmacology 27, no. 4 (April 1996): 462–68. http://dx.doi.org/10.1097/00005344-199604000-00002.

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28

de Oliveira, Rubens Marona, Bartira Ercília Pinheiro da Costa, Fernando Custódio Fervenza, Mário Bernardes Wagner, Domingos Otavio d'Avila, and Carlos Eduardo Poli de Figueiredo. "Effect of Radiocontrasts on Selected Membrane Transport Systems." Renal Failure 27, no. 6 (January 2005): 727–32. http://dx.doi.org/10.1080/08860220500243247.

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OSUMI, Yoshinori. "Transport systems of vacuolor membrane from S. cerevisiae." Seibutsu Butsuri 25, no. 4 (1985): 156–61. http://dx.doi.org/10.2142/biophys.25.156.

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Davis, James C., Ronald J. Valus, Reza Eshraghi, and Alex E. Velikoff. "Facilitated Transport Membrane Hybrid Systems for Olefin Purification." Separation Science and Technology 28, no. 1-3 (January 1993): 463–76. http://dx.doi.org/10.1080/01496399308019500.

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31

Cullis, P. "pH gradients and membrane transport in liposomal systems." Trends in Biotechnology 9, no. 1 (January 1991): 268–72. http://dx.doi.org/10.1016/0167-7799(91)90088-y.

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Cavaliere, Matteo, and Sean Sedwards. "Membrane Systems with Peripheral Proteins: Transport and Evolution." Electronic Notes in Theoretical Computer Science 171, no. 2 (July 2007): 37–53. http://dx.doi.org/10.1016/j.entcs.2007.05.006.

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33

Nikonenko, Victor, and Natalia Pismenskaya. "Ion and Molecule Transport in Membrane Systems 2.0." International Journal of Molecular Sciences 22, no. 7 (March 29, 2021): 3533. http://dx.doi.org/10.3390/ijms22073533.

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34

Enouf, J., R. Bredoux, N. Bourdeau, B. Sarkadi, and S. Levy-Toledano. "Further characterization of the plasma membrane- and intracellular membrane-associated platelet Ca2+ transport systems." Biochemical Journal 263, no. 2 (October 15, 1989): 547–52. http://dx.doi.org/10.1042/bj2630547.

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Biochemical characterization of the Ca2+-ATPases isolated from human platelet intracellular and plasma membranes is reported. A comparative study of the previously partly described plasma membrane Ca2+-ATPase [Enouf, Bredoux, Bourdeau & Levy-Toledano (1987) J. Biol. Chem. 261, 9293-9297] and the intracellular membrane Ca2+-ATPase obtained simultaneously shows differences in the following parameters: (1) different kinetics of the two enzymes; (2) similar apparent affinity towards Ca2+ (10(-7) M), though the intracellular membrane enzyme was inhibited at Ca2+ concentrations above 10(-6) M; (3) different pH dependence with an activity maximum at pH 7 for the intracellular membrane Ca2+-ATPase and no detectable pH maximum for the plasma membrane Ca2+-ATPase; (4) a 10-fold difference in the ATP requirement of the two Ca2+-ATPases; (5) different patterns of inhibition by vanadate. Finally, the possible regulation of the Ca2+-ATPases was examined by studying the effect of chlorpromazine on the two Ca2+-ATPase activities, with only the plasma membrane enzyme being inhibited. It is concluded that the two platelet Ca2+ transport systems show biochemical differences in spite of the previously shown similarity in the molecular masses of their Ca2+-ATPases, thus conferring a definite specificity to the platelet system.

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HANOZET, GIORGIO M., BARBARA GIORDANA, V. FRANCA SACCHI, and PAOLO PARENTI. "AMINO ACID TRANSPORT SYSTEMS IN BRUSH-BORDER MEMBRANE VESICLES FROM LEPIDOPTERAN ENTEROCYTES." Journal of Experimental Biology 143, no. 1 (May 1, 1989): 87–100. http://dx.doi.org/10.1242/jeb.143.1.87.

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The presence of different potassium-dependent amino acid transport systems in the luminal membrane of the larval midgut of Philosamia cynthia Drury (Saturnidae, Lepidoptera) was investigated by means of countertransport experiments performed with brush-border membrane vesicles. The vesicles were preloaded with 14 different unlabelled amino acids, whose ability to elicit an intravesicular accumulation over the equilibrium value of six labelled amino acids (L-alanine, L-leucine, L-phenylalanine, L-glutamic acid, L-lysine and L-histidine) was tested. For histidine, the results were compared with those obtained from inhibition experiments, in which the same 14 amino acids were used as inhibitors on the cis side of the brush-border membrane. The data demonstrate the presence in the lepidopteran luminal membrane of distinct transport pathways for lysine and glutamic acid. The transport of most neutral amino acids, with the exclusionof glycine and proline, seems to occur through a system that may be similar to the neutral brush-border system (NBB) found in mammalian intestinal membranes. This system is also able to handle histidine.

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Burganos, Vasilis N. "Membranes and Membrane Processes." MRS Bulletin 24, no. 3 (March 1999): 19–22. http://dx.doi.org/10.1557/s0883769400051861.

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Membrane separation science has enjoyed tremendous progress since the first synthesis of membranes almost 40 years ago, which was driven by strong technological needs and commercial expectations. As a result, the range of successful applications of membranes and membrane processes is continuously broadening. An additional change lies in the nature of membranes, which is now extended to include liquid and gaseous materials, biological or synthetic. Membranes are understood to be thin barriers between two phases through which transport can take place under the action of a driving force, typically a pressure difference and generally a chemical or electrical potential difference.An attempt at functional classification of membranes would have to include diverse categories such as gas separation, pervaporation, reverse osmosis, micro- and ultrafiltration, and biomedical separations. The dominant application of membranes is certainly the separation of mixed phases or fluids, homogeneous or heterogeneous. Separation of a mixture can be achieved if the difference in the transport coefficients of the components of interest is sufficiently large. Membranes can also be used in applications other than separation targeting: They can be employed in catalytic reactors, energy storage and conversion systems, as key components of artificial organs, as supports for electrodes, or even to control the rate of release of both useful and dangerous species.In order to meet the requirements posed by the aforementioned applications, membranes must combine several structural and functional properties.

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Fedorova, E., A. Nalobina, and A. Sizov. "ATPASE ERYTHROCYTE TRANSPORT SYSTEMS IN HUMAN BLOOD." Human Sport Medicine 19, S1 (August 17, 2019): 61–67. http://dx.doi.org/10.14529/hsm19s108.

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Aim. The article deals with establishing the features of ATPase erythrocytes in the athletes of the first and second categories and non-athletes from different age groups. Material and methods. We studied the capillary blood of track-and-field athletes and healthy non-athletes of the same age and anthropometric characteristics (n = 60). Blood analysis was performed with the help of the Dixion hematological analyzer (Russia). The activity of erythrocyte membrane ATPases was studied according to K.S. Keeton. Results. The study revealed significant (p < 0.05) differences in certain (HGB and RBC) hematological blood indicators in participants from different age groups depending on their physical fitness. Age differences between groups are not significant (p > 0.05). The results obtained demonstrate the significantly (p < 0.001) higher values of ATPase activity in the athletes of the first and second categories from various age groups. The increase in Mg2+, Na+, K+-, Mg2+- and Na+, K+-ATPases activity in athletes is connected with more intensive metabolism in this group because transport ATPases participate in the energy supply of training and competition loads. Age-related differences (p < 0.05) in the activity of erythrocyte membrane ATPases in both groups can be possibly connected with the conformation features of erythrocyte membrane protein. The two-factor dispersion analysis revealed that age significantly (Р < 0.001) determined Mg2+, Na+, K+-, Mg2+- and Na+, K+-ATPases erythrocyte membrane activity at 89.15, 87.46, and 81.40 % respectively; physical activity at 96.19, 95.45 and 93.80 % respectively. Conclusion. General physical fitness and age can be considered as the factors determining the activity of erythrocyte membrane ATPases.

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Vasilev, V. V., and I. S. Vasileva. "Inter-hospital transport on extracorporeal membrane oxygenation in various health systems." EMERGENCY MEDICAL CARE 22, no. 2 (June 8, 2021): 64–68. http://dx.doi.org/10.24884/2072-6716-2021-22-2-64-68.

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The feasibility and the recognition of the possibility to transport patients on extracorporeal membrane oxygenation (ECMO) aroused in the 1970s. The number of transporting facilities worldwide was less than 20 in the beginning of the second Millennium. In 2009 the H1N1 pandemic and a publication showing survival benefit for adult patients transported to a hospital with ECMO resource increased both awareness and interest for ECMO treatment. The number of transport organizations increased rapidly. As of today, the number of transport organizations increases world-wide, though some centers where ECMO is an established treatment report decreasing numbers of transports. Since the introduction of the more user-friendly equipment (ECMO-2 era) increasing numbers of low-volume ECMO centers perform these complex treatments. This overview is based on the current literature, personal experience in the field, and information from the authors’ network on the organization of ECMO transport systems in different settings of health care around the globe. Registry data since the entry into ECMO-2 shows that the number of ECMO treatments matter. The more treatments performed at a given center the better the patient outcome, and the better these resources are spent for the population served. A Hub-and-S poke model for national or regional organization for respiratory ECMO (rECMO) should be advocated where central high-volume ECMO center (Hub) serves a population of 10 to 15 million. Peripheral units (Spokes) play an important part in emergency cannulations keeping the patient on ECMO support till a mobile ECMO team retrieves the patient. This ECMO team is preferably organized from the Hub and brings competencies for assessment and decision to initiate ECMO treatment bedside at any hospital, for cannulation, and a safe transport to any destination.

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Miyamoto, Y., J. L. Coone, V. Ganapathy, and F. H. Leibach. "Distribution and properties of the glycylsarcosine-transport system in rabbit renal proximal tubule. Studies with isolated brush-border-membrane vesicles." Biochemical Journal 249, no. 1 (January 1, 1988): 247–53. http://dx.doi.org/10.1042/bj2490247.

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The distribution and properties of the peptide-transport system in rabbit renal proximal tubule was examined with glycylsarcosine as the substrate and using brush-border-membrane vesicles derived from pars convoluta (outer cortex) and pars recta (outer medulla). The dipeptide was transported into these vesicles against a concentration gradient in the presence of an inward-directed H+ gradient, demonstrating the presence of a H+-coupled peptide-transport system in outer-cortical as well as outer-medullary brush-border membranes. Even though the transport was electrogenic and was energized by a H+ gradient in both membranes, the system was more active in outer medullary membranes than in outer cortical membranes. Kinetic analysis showed that, although the affinity of the transport system for glycylsarcosine was similar in both membrane preparations, the capacity of the system was significantly greater in outer medulla than in outer cortex. In addition, the pH profiles of the peptide-transport systems in these membrane preparations also showed dissimilarities. The greater dipeptide uptake in one membrane vis-à-vis the other may probably be due to the difference in the affinity of the transport system for H+ and/or the difference in peptide/H+ stoichiometry.

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Bian, Rulin, Yoshimasa Watanabe, Norihito Tambo, and Genzo Ozawa. "Removal of Humic Substances by UF and NF Membrane Systems." Water Science and Technology 40, no. 9 (November 1, 1999): 121–29. http://dx.doi.org/10.2166/wst.1999.0458.

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This paper deals with the removal efficiency and mechanisms of humic substances contained in a river water by ultrafiltration (UF) and nanofiltration (NF) membranes. UF membranes with molecular weight cut-off (MWCO) of 50 kDa to 200 kDa can remove only large molecular size humic substances (LMSHS). Even in the UF membranes operated under the cross-flow mode, the LMSHS were accumulated on the membrane surface, because the back transport velocity of LMSHS is always smaller than that of the permeate flux. Precoagulation enhanced the removal of humic substances effectively. The optimum coagulation conditions for removing the humic substances in the UF membranes was the same as that in the conventional coagulation/flocculation/sedimentation process. The vibration action increased the removal efficiency of humic substances in the NF membrane process. Strong shear produced by the vibration diffused away the humic substances from the membrane surface to the bulk water, therefore the accumulation of humic substances on/near the membrane surface, i.e. formation of cake and concentration polarization boundary layers, is prohibited.

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41

Sanders, D. "Kinetic Modeling of Plant and Fungal Membrane Transport Systems." Annual Review of Plant Physiology and Plant Molecular Biology 41, no. 1 (June 1990): 77–107. http://dx.doi.org/10.1146/annurev.pp.41.060190.000453.

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42

Lijnen, Paul, Robert Fagard, Jan Staessen, Lutgarde Thijs, and Antoon Amery. "Erythrocyte membrane lipids and cationic transport systems in men." Journal of Hypertension 10, no. 10 (October 1992): 1205–11. http://dx.doi.org/10.1097/00004872-199210000-00014.

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Mansour, Mohamed Magdy F. "The plasma membrane transport systems and adaptation to salinity." Journal of Plant Physiology 171, no. 18 (November 2014): 1787–800. http://dx.doi.org/10.1016/j.jplph.2014.08.016.

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44

Izatt, R. M., G. A. Clark, J. S. Bradshaw, J. D. Lamb, and J. J. Christensen. "Macrocycle-Facilitated Transport of Ions in Liquid Membrane Systems." Separation and Purification Methods 15, no. 1 (January 1986): 21–72. http://dx.doi.org/10.1080/03602548608068424.

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45

LIJNEN, P. "D11 Cell membrane cation transport systems during aldosterone antagonism." American Journal of Hypertension 10, no. 4 (April 1997): 41A. http://dx.doi.org/10.1016/s0895-7061(97)88785-7.

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46

Ren, Q. "TransportDB: a relational database of cellular membrane transport systems." Nucleic Acids Research 32, no. 90001 (January 1, 2004): 284D—288. http://dx.doi.org/10.1093/nar/gkh016.

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47

Quesada, A. R., and J. D. McGivan. "A rapid method for the functional reconstitution of amino acid transport systems from rat liver plasma membranes. Partial purification of System A." Biochemical Journal 255, no. 3 (November 1, 1988): 963–69. http://dx.doi.org/10.1042/bj2550963.

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A rapid method for the functional reconstruction of amino acid transport from liver plasma-membrane vesicles using the neutral detergent decanoyl-N-glucamide (‘MEGA-10’) is described. The method is a modification of that previously employed in this laboratory for reconstitution of amino acid transport systems from kidney brush-border membranes [Lynch & McGivan (1987) Biochem. J. 244, 503-508]. The transport activities termed ‘System A’, ‘System N’, and ‘System L’ are all reconstituted. The reconstitution procedure is rapid and efficient and is suitable as an assay for transport activity in studies involving membrane fractionation. By using this reconstitution procedure, System A transport activity was partially purified by lectin-affinity chromatography.

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48

Brzezińska, A., P. Wińska, and M. Balińska. "Cellular aspects of folate and antifolate membrane transport." Acta Biochimica Polonica 47, no. 3 (September 30, 2000): 735–49. http://dx.doi.org/10.18388/abp.2000_3992.

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Folates--one carbon carriers--take part in the metabolism of purine, thymidylate and some amino acids. Internalization of these compounds employs several mechanisms of transport systems. Reduced folate carriers and folate receptors play the most important role in this process. The physiological role of these molecules in normal and neoplastic cells is described regarding changes in transport activity and connection of transport systems with resistance to antifolates and cancer development.

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49

Lee, Wha-Joon, Richard A. Hawkins, Juan R. Viña, and Darryl R. Peterson. "Glutamine transport by the blood-brain barrier: a possible mechanism for nitrogen removal." American Journal of Physiology-Cell Physiology 274, no. 4 (April 1, 1998): C1101—C1107. http://dx.doi.org/10.1152/ajpcell.1998.274.4.c1101.

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Glutamine and glutamate transport activities were measured in isolated luminal and abluminal plasma membrane vesicles derived from bovine brain endothelial cells. Facilitative systems for glutamine and glutamate were almost exclusively located in luminal-enriched membranes. The facilitative glutamine carrier was neither sensitive to 2-aminobicyclo(2,2,1)heptane-2-carboxylic acid inhibition nor did it participate in accelerated amino acid exchange; it therefore appeared to be distinct from the neutral amino acid transport system L1. Two Na-dependent glutamine transporters were found in abluminal-enriched membranes: systems A and N. System N accounted for ∼80% of Na-dependent glutamine transport at 100 μM. Abluminal-enriched membranes showed Na-dependent glutamate transport activity. The presence of 1) Na-dependent carriers capable of pumping glutamine and glutamate from brain into endothelial cells, 2) glutaminase within endothelial cells to hydrolyze glutamine to glutamate and ammonia, and 3) facilitative carriers for glutamine and glutamate at the luminal membrane may provide a mechanism for removing nitrogen and nitrogen-rich amino acids from brain.

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Ferrand, Aurélie, Julia Vergalli, Jean-Marie Pagès, and Anne Davin-Regli. "An Intertwined Network of Regulation Controls Membrane Permeability Including Drug Influx and Efflux in Enterobacteriaceae." Microorganisms 8, no. 6 (June 1, 2020): 833. http://dx.doi.org/10.3390/microorganisms8060833.

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The transport of small molecules across membranes is a pivotal step for controlling the drug concentration into the bacterial cell and it efficiently contributes to the antibiotic susceptibility in Enterobacteriaceae. Two types of membrane transports, passive and active, usually represented by porins and efflux pumps, are involved in this process. Importantly, the expression of these transporters and channels are modulated by an armamentarium of tangled regulatory systems. Among them, Helix-turn-Helix (HTH) family regulators (including the AraC/XylS family) and the two-component systems (TCS) play a key role in bacterial adaptation to environmental stresses and can manage a decrease of porin expression associated with an increase of efflux transporters expression. In the present review, we highlight some recent genetic and functional studies that have substantially contributed to our better understanding of the sophisticated mechanisms controlling the transport of small solutes (antibiotics) across the membrane of Enterobacteriaceae. This information is discussed, taking into account the worrying context of clinical antibiotic resistance and fitness of bacterial pathogens. The localization and relevance of mutations identified in the respective regulation cascades in clinical resistant strains are discussed. The possible way to bypass the membrane/transport barriers is described in the perspective of developing new therapeutic targets to combat bacterial resistance.

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Journal articles on the topic 'Membrane transport systems'

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