Journal ArticleDOI
Charge transfer mediated by nigericin in black lipid membranes.
TLDR
The dependence of the membrane conductance on pH and K+ concentration suggests a mechanism for the transfer of charge mediated by this ionophore based on a mobile dimer with both nigericin molecules protonated and complexed with one K+.Abstract:
Nigericin, in the concentration range (10−6M or higher) at which it uncouples intact mitochondria, was found to increase the conductance of black lipid membranes (BLM) by several orders of magnitude The dependence of the membrane conductance on pH and K+ concentration suggests a mechanism for the transfer of charge mediated by this ionophore based on a mobile dimer with both nigericin molecules protonated and complexed with one K+ This charged complex accounts for the uncoupling effect observed in intact mitochondriaread more
Citations
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Journal ArticleDOI
Mitochondrial targets of drug toxicity.
TL;DR: The significance is further underscored by the recent identification of bioenergetic control points for cell replication and differentiation and the realization that mitochondria play a determinant role in cell signaling and apoptotic modes of cell death.
Journal ArticleDOI
The acrosome reaction of Strongylocentrotus purpuratus sperm. Ion requirements and movements.
TL;DR: In this paper, an increase in 86Rb+ permeability accompanied the acrosome reaction, suggesting that movement of K+ is an important effector of the reaction, which may be triggered with nigericin, an ionophore that catalyzes the electrically neutral exchange of K and H+ across membranes.
Journal ArticleDOI
ATP-linked calcium transport in cells and membrane vesicles of Streptococcus faecalis.
TL;DR: It is concluded that in this organism calcium uptake is not energized by the proton circulation but by ATP itself, what appears to be the first description of a bacterial vesicle preparation that retains an ATP-linked transport system.
Journal ArticleDOI
Bacteriorhodopsin in liposomes. II. Experimental evidence in support of a theoretical model
TL;DR: In three independent experimental systems evidence was obtained for the correctness of the postulated dependence of the turnover rate of the photochemical cycle on back pressure by the transmembrane electrochemical potential difference for protons.
Journal ArticleDOI
The use of valinomycin, nigericin and trichlorocarbanilide in control of the protonmotive force in Escherichia coli cells.
TL;DR: Valinomycin, nigericin and trichlorocarbanilide were assessed for their ability to control the protonmotive force in Escherichia coli cells and Nigericin was found to have two modes of action.
References
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Journal ArticleDOI
Chemiosmotic coupling in oxidative and photosynthetic phosphorylation
TL;DR: The end result of the coupling between the flows through the o/r and h/d pathways in oxidative phosphorylation in mitochondria is that, for the equivalent of each pair of electrons traversing the respiratory chain, up to 3 anhydro-bond equivalents may normally traverse the h/D pathway from adenosine diphosphate plus inorganic phosphate (ADP +Pi) to water.
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Reconstitution of Cell Membrane Structure in vitro and its Transformation into an Excitable System
TL;DR: By forming such a membrane between two compartments filled with saline its transverse electrical properties can be measured, and controlled chemical investigations can be undertaken.
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Chromatographically homogeneous lecithin from egg phospholipids.
TL;DR: The modified method involved application of crude egg phosphatides to a column of alumina in the proportion of 1 g phosphatide/25 g alumina, and elution of the lecithin fraction with the 2-component solvent system chloroform:methanol, 9:1 by vol.
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The action of certain antibiotics on mitochondrial, erythrocyte and artificial phospholipid membranes. The role of induced proton permeability.
TL;DR: The action of enniatin A, valinomycin, the actin homologues, gramicidin, nigericin and dianemycin on mitochondrial respiration could be accounted for by changes in passive ion permeability of the mitochondrial membrane similar to those induced in erythrocytes and phospholipid membranes, if it is assumed that a membrane potential is present in respiring mitochondria.
Journal ArticleDOI
Antibiotic-mediated transport of alkali ions across lipid barriers.
TL;DR: It is established that both classes of antibiotics act analogously in many respects, both in mitochondria and in a variety of other lipid barrier systems, as well as to reverse transport induced by the valinomycin class.