Anomalous response of oxonol-V to membrane potential in mitochondrial proton pumps.
AuthorsAhmed I, Krishnamoorthy G
JournalBiochim Biophys Acta
PubMed ID7947900
The response of the fluorescent membrane potential probe oxonol-V (bis[3-phenyl 5 oxoisoxazol-4-yl]pentamethine oxonol) in submitochondrial particles (SMP) was dependent upon whether the potential (inside positive) was generated by active proton pumps or by valinomycin-aided passive K+ influx. The fluorescence intensity showed a decrease in the former case and an increase ... More
Na,K-ATPase in artificial lipid vesicles. Comparison of Na,K and Na-only pumping mode.
AuthorsApell HJ, Häring V, Roudna M
JournalBiochim Biophys Acta
PubMed ID2156565
Na,K-ATPase from rabbit kidney outer medulla was reconstituted in large unilamellar lipid vesicles by detergent dialysis. Vesicles prepared in the presence or absence of potassium allowed to study two different transport modes: the (physiological) Na,K-mode in buffers containing Na+ and K+ and the Na-only mode in buffers containing Na+ but ... More
An anion binding site that regulates the glutamate transporter of synaptic vesicles.
AuthorsHartinger J, Jahn R
JournalJ Biol Chem
PubMed ID8226829
'Glutamate, the major excitatory neurotransmitter of the mammalian central nervous system, is stored in synaptic vesicles and released by exocytosis upon depolarization of the presynaptic nerve terminal. Synaptic vesicles possess an active glutamate-specific transporter that is driven by an electrochemical proton gradient across the vesicle membrane and requires chloride for ... More
Characterization of a P-type Na+-ATPase of a facultatively anaerobic alkaliphile, Exiguobacterium aurantiacum.
AuthorsUeno S, Kaieda N, Koyama N
JournalJ Biol Chem
PubMed ID10799538
'A facultatively anaerobic alkaliphile, Exiguobacterium aurantiacum, possesses a P-type Na(+)-stimulated ATPase in the membrane (Koyama, N. (1999) Curr. Microbiol. 39, 27-30). In this study, we attempted to purify and characterize the enzyme. The ATPase appears to consist of a single polypeptide with an apparent molecular mass of 100 kDa. The ... More
Oxonol VI as an optical indicator for membrane potentials in lipid vesicles.
AuthorsApell HJ, Bersch B
JournalBiochim Biophys Acta
PubMed ID2444259
'Experiments with large unilamellar dioleoylphosphatidylcholine vesicles were carried out in order to study the effect of membrane potential on the fluorescence of Oxonol VI. A partition equilibrium of dye between membrane and water was found to exist with a partition coefficient gamma identical to c lipid/c water of about 19,000 ... More
Voltage-sensitive oxonol dyes are novel large-conductance Ca2+-activated K+ channel activators selective for beta1 and beta4 but not for beta2 subunits.
'The large-conductance Ca(2+)-activated K(+) (BK) channel is activated by both the increase of intracellular Ca(2+) concentration and membrane depolarization. The BK channel plays crucial roles as a key molecule in the negative feedback mechanism regulating membrane excitability and cellular Ca(2+) in various cell types. Here, we report that a widely ... More
Proton-motive force stimulates the proteolytic activity of FtsH, a membrane-bound ATP-dependent protease in Escherichia coli.
AuthorsAkiyama Y
JournalProc Natl Acad Sci U S A
PubMed ID12034886
'FtsH is a membrane-bound, ATP-dependent metalloprotease in Escherichia coli that degrades some integral membrane proteins and cytoplasmic proteins. In this study, we show that FtsH-dependent degradation of both membrane-bound and soluble proteins is retarded when cells are treated with carbonyl cyanide-3-chlorophenylhydrazone or 2,4-dinitrophenol uncouplers, which dissipate the proton-motive force. In ... More
Protein-independent lead permeation through myelin lipid liposomes.
AuthorsDíaz RS, Monreal J
JournalMol Pharmacol
PubMed ID7723737
'We have investigated the permeability of protein-free myelin lipid liposomes to inorganic lead by using the fluorescent probes fura-2, oxonol V, pyranine, and carboxyfluorescein. Inorganic lead readily crossed the lipid bilayer, as detected with fura-2, to an extent that depended on the external pH and the total nominal lead concentration ... More
Generation of a membrane potential by sodium-dependent succinate efflux in Selenomonas ruminantium.
AuthorsMichel TA, Macy JM
JournalJ Bacteriol
PubMed ID2307654
'When Selenomonas ruminantium HD4 was grown in a chemostat, maximal succinate production and the highest molar growth yield values were both observed at a dilution rate of roughly 0.2 h-1. To determine the possible relationship between succinate efflux and high molar growth yields, the generation of a membrane potential by ... More
Electrochemical potential and ion transport in vesicles of yeast plasma membrane.
AuthorsCalahorra M, Ramírez J, Clemente SM, Peña A
JournalBiochim Biophys Acta
PubMed ID2883994
'Vesicles from yeast plasma membrane were prepared according to Franzusoff and Cirillo [1983) J. Biol. Chem. 258, 3608), with slight modifications. When Mg-ATP was added, this preparation was able to generate a membrane potential, that was sensitive to inhibitors of the yeast H+-ATPase and uncouplers, and could be decreased by ... More
Electrogenic pump current of sarcoplasmic reticulum Ca(2+)-ATPase reconstituted at high lipid/protein ratio.
AuthorsCornelius F, Møller JV
JournalFEBS Lett
PubMed ID1829418
'When Ca(2+)-ATPase from sarcoplasmic reticulum was reconstituted with excess phospholipid (at a 1:800 weight ratio) in a monomeric state and activated by Ca2+ and ATP a transmembrane potential developed which could be continuously recorded by the fluorochrome oxonol VI. The results demonstrate the electrogenicity of active Ca2+ transport during continuous ... More
Regulatory volume decrease of cultured human fibroblasts involves changes in intracellular amino-acid pool.
AuthorsDall'Asta V, Rossi PA, Bussolati O, Gazzola GC
JournalBiochim Biophys Acta
PubMed ID8312358
'Regulatory volume decrease (RVD) has been studied in cultured human fibroblasts incubated in a complete growth medium at low osmolality (215 mosmolal). After the initial swelling induced by hypotonic treatment, cells recover their volume almost completely within about 60 min. This RVD is associated with comparable losses of cell potassium ... More
Na+/H+ exchange activity in the plasma membrane of Arabidopsis.
'In plants, Na+/H+ exchangers in the plasma membrane are critical for growth in high levels of salt, removing toxic Na+ from the cytoplasm by transport out of the cell. The molecular identity of a plasma membrane Na+/H+ exchanger in Arabidopsis (SOS1) has recently been determined. In this study, immunological analysis ... More
Proton translocating ATPase in lysosomal membrane ghosts. Evidence that alkaline Mg2+-ATPase acts as a proton pump.
AuthorsMoriyama Y, Takano T, Ohkuma S
JournalJ Biochem (Tokyo)
PubMed ID6146604
'Membrane ghosts were prepared from purified lysosomes (tritosomes) of rat liver by hypo-osmotic treatment. Mg2+-ATP-driven acidification was observed in the membrane ghosts using acridine orange as a fluorescent probe of the transmembrane pH gradient (delta pH). Its properties were the same as those of intact lysosomes reported previously (Ohkuma, S., ... More
Oxonol dyes as monitors of membrane potential. Their behavior in photosynthetic bacteria.
AuthorsBashford CL, Chance B, Prince RC
JournalBiochim Biophys Acta
PubMed ID103582
'The reponses of oxonol dyes to single and multiple single turnovers of the photosynthetic apparatus of photosynthetic bacteria have been studied, and compared with the responses of the endogenous carotenoid pigments. The absorbance changes of the oxonols can be conveniently measured at 587 nm, because this is an isosbestic point ... More
Oxonol dyes as monitors of membrane potential: the effect of viruses and toxins on the plasma membrane potential of animal cells in monolayer culture and in suspension.
AuthorsBashford CL, Alder GM, Gray MA, Micklem KJ, Taylor CC, Turek PJ, Pasternak CA
JournalJ Cell Physiol
PubMed ID3988810
'Optical indicators of the cationic, cyanine and anionic oxonol classes were used to evaluate the plasma membrane potential of animal cells in suspension and in monolayer culture. The optical signals were calibrated by using diffusion potentials either of K+ (in the presence of valinomycin) or of H+ (in the presence ... More
Glycolysis and glutamate accumulation into synaptic vesicles. Role of glyceraldehyde phosphate dehydrogenase and 3-phosphoglycerate kinase.
AuthorsIkemoto A, Bole DG, Ueda T
JournalJ Biol Chem
PubMed ID12488440
'Glucose is the major source of brain energy and is essential for maintaining normal brain and neuronal function. Hypoglycemia causes impaired synaptic transmission. This occurs even before significant reduction in global cellular ATP concentration, and relationships among glycolysis, ATP supply, and synaptic transmission are not well understood. We demonstrate that ... More
Membrane energization at subzero temperatures: calcium uptake and oxonol-V responses.
AuthorsChance B, Nakase Y, Itshak F
JournalArch Biochem Biophys
PubMed ID518090
The behavior of oxonol dyes in phospholipid dispersions.
AuthorsBashford CL, Chance B, Smith JC, Yoshida T
JournalBiophys J
PubMed ID263685
Dye indicators of membrane potential.
AuthorsWaggoner AS
JournalAnnu Rev Biophys Bioeng
PubMed ID383007
Kinetics of the association of potential-sensitive dyes with model and energy-transducing membranes: implications for fast probe response times.
AuthorsSmith JC, Frank SJ, Bashford CL, Chance B, Rudkin B
JournalJ Membr Biol
PubMed ID7401166
Potential-sensitive molecular probes in membranes of bioenergetic relevance.
AuthorsSmith JC
JournalBiochim Biophys Acta
PubMed ID2178682
The use of optical probes to monitor membrane potential.
AuthorsBashford CL, Smith JC
JournalMethods Enzymol
PubMed ID459857
Optical measurement of membrane potential in cells, organelles, and vesicles.
AuthorsFreedman JC, Novak TS
JournalMethods Enzymol
PubMed ID2747524
ATPase activity and ATP-dependent proton translocation in plasma membrane vesicles of turtle bladder epithelial cells.
AuthorsYoumans SJ, Worman HJ, Brodsky WA
JournalBiochim Biophys Acta
PubMed ID6219707
ATP-induced quenching of fluorescence of acridine orange (a pH probe) or Oxonol V (a potential difference probe) is evoked in turtle bladder membrane vesicles in suspending media of appropriate ionic composition and is insensitive to oligomycin, valinomycin, and ouabain. These effects are ascribed to a membrane-bound, ouabain-resistant ATPase which mediates ... More
Generation of plasma membrane potential by the Na+-pump coupled to proton extrusion.
AuthorsBashford CL, Pasternak CA
JournalEur Biophys J
PubMed ID2412812
Lettré cells maintain a plasma membrane potential near -60 mV, yet are scarcely depolarized by 80 mM Rb+ and are relatively impermeable to 86Rb+. They are depolarized by ouabain without a concomitant change in intracellular cation content. Addition of K+ to cells suspended in a K+ free medium, or of ... More
Experimental verification of a sequence-based prediction: F(1)F(0)-type ATPase of Vibrio cholerae transports protons, not Na(+) ions.
AuthorsDzioba J, Häse CC, Gosink K, Galperin MY, Dibrov P
JournalJ Bacteriol
PubMed ID12511516
The membrane energetics of the intestinal pathogen Vibrio cholerae involves both H(+) and Na(+) as coupling ions. The sequence of the c subunit of V. cholerae F(0)F(1) ATPase suggested that this enzyme is H(+) specific, in contrast to the results of previous studies on the Na(+)-dependent ATP synthesis in closely ... More
Plasma membrane potential of neutrophils generated by the Na+ pump.
AuthorsBashford CL, Pasternak CA
JournalBiochim Biophys Acta
PubMed ID2408670
The plasma membrane potential of human neutrophils was monitored using the anionic dye oxonol-V. The cells maintain a potential of -75 +/- 17 mV when suspended in physiological saline solutions. The cells are scarcely depolarized by extracellular K+ and the depolarization induced by the chemotactic peptide fMet-Leu-Phe is of similar ... More
Metabolic modulation of transport coupling ratio in yeast plasma membrane H(+)-ATPase.
AuthorsVenema K, Palmgren MG
JournalJ Biol Chem
PubMed ID7642655
The plasma membrane proton pump (H(+)-ATPase) of yeast energizes solute uptake by secondary transporters and regulates cytoplasmic pH. The addition of glucose to yeast cells stimulates proton efflux mediated by the H(+)- ATPase. A > 50-fold increase in proton extrusion from yeast cells is observed in vivo, whereas the ATPase ... More
The mechanism of potassium movement across the liposomal membrane.
AuthorsCooper CE, Wrigglesworth JM, Nicholls P
JournalBiochem Biophys Res Commun
PubMed ID2268307
Addition of potassium to sodium-loaded asolectin liposomes induces an internal alkalinization even in the absence of ionophores. Most of the K+ entry is electrogenic, as shown by fluorescent changes in the potential-sensitive probe Oxonol V. The major part of the proton efflux observed must therefore be electrophoretic. However, in the ... More
Sodium cotransport systems and the membrane potential difference.
AuthorsEddy AA
JournalAnn N Y Acad Sci
PubMed ID2418734
Studies with membrane vesicles and with whole cell preparations have shown clearly that the electrochemical gradient of Na+ acting across the cell membrane is closely coupled to the influx and efflux of amino acids or carbohydrates through their cellular pumps. It has been less clear (1) just how tightly solute ... More
Charge shift optical probes of membrane potential. Theory.
AuthorsLoew LM, Bonneville GW, Surow J
JournalBiochemistry
PubMed ID708694
The chromophores of a series of known and unknown probes of membrane potential are subjected to molecular orbital calculations. These calculations are used to characterize the charge distribution and excitation-induced shift of electron density in the chromophores. This is used to predict or rationalize the magnitude of an electrochromic response ... More
Oxonol-V as a probe of chromaffin granule membrane potentials.
AuthorsScherman D, Henry JP
JournalBiochim Biophys Acta
PubMed ID7397145
The dye, oxonol-V (bis(3-phenyl-5-oxoisoxazol-4-yl)pentamethine oxonol), can be used to estimate the transmembrane potential of chromaffin granules. The potentials result either from a resting-state Donnan equilibrium (inside negative at pH 6.6) or from an ATP-driven proton pump. The fluorescence and absorption changes generated by ATP addition depended on the pH of ... More
The plasma membrane potential of human neutrophils. Role of ion channels and the sodium/potassium pump.
AuthorsMajander A, Wikström M
JournalBiochim Biophys Acta
PubMed ID2539191
Calcium-depleted human neutrophils are depolarised when suspended in calcium-free media containing sodium ions, and are repolarised by extracellular replenishment of Ca2+. The depolarisation is due to a high inward sodium current, which is blocked by calcium and by several other divalent cations, but not by barium. Addition of calcium results ... More
A stopped-flow kinetic study of the interaction of potential-sensitive oxonol dyes with lipid vesicles.
AuthorsClarke RJ, Apell HJ
JournalBiophys Chem
PubMed ID2611347
The interaction of the dyes oxonol V and oxonol VI with unilamellar dioleoylphosphatidylcholine vesicles was investigated using a fluorescence stopped-flow technique. On mixing with the vesicles, both dyes exhibit an increase in their fluorescence, which occurs in two phases. According to the dependence of the reciprocal relaxation time on vesicle ... More
The Escherichia coli multidrug transporter MdfA catalyzes both electrogenic and electroneutral transport reactions.
AuthorsLewinson O, Adler J, Poelarends GJ, Mazurkiewicz P, Driessen AJ, Bibi E
JournalProc Natl Acad Sci U S A
PubMed ID12578981
The resistance of cells to many drugs simultaneously (multidrug resistance) often involves the expression of membrane transporters (Mdrs); each recognizes and expels a broad spectrum of chemically unrelated drugs from the cell. The Escherichia coli Mdr transporter MdfA is able to transport differentially charged substrates in exchange for protons. This ... More
Ratiometric fluorescence measurements of membrane potential generated by yeast plasma membrane H(+)-ATPase reconstituted into vesicles.
AuthorsHoloubek A, Vecer J, Opekarová M, Sigler K
JournalBiochim Biophys Acta
PubMed ID12507760
Potential-sensitive fluorescent probes oxonol V and oxonol VI were employed for monitoring membrane potential (Delta(psi)) generated by the Schizosaccharomyces pombe plasma membrane H(+)-ATPase reconstituted into vesicles. Oxonol VI was used for quantitative measurements of the Delta(psi) because its response to membrane potential changes can be easily calibrated, which is not ... More
Voltage sensitivity of H+/Ca2+ antiport in higher plant tonoplast suggests a role in vacuolar calcium accumulation.
AuthorsBlackford S, Rea PA, Sanders D
JournalJ Biol Chem
PubMed ID2351660
The electrogenicity of H+/Ca2+ exchange in vacuolar membrane (tonoplast) vesicles from Beta was studied to elucidate the role of this transport system in vacuolar Ca2+ accumulation. To overcome the inherently high proton permeability of tonoplast vesicles, the pH difference established by the primary H(+)-ATPase was titrated to a uniform value ... More
As(III) and Sb(III) uptake by GlpF and efflux by ArsB in Escherichia coli.
AuthorsMeng YL, Liu Z, Rosen BP
JournalJ Biol Chem
PubMed ID14970228
The toxicity of the metalloids arsenic and antimony is related to uptake, whereas detoxification requires efflux. In this report we show that uptake of the trivalent inorganic forms of arsenic and antimony into cells of Escherichia coli is facilitated by the aquaglyceroporin channel GlpF and that transport of Sb(III) is ... More
Quantitative measurement of cationic fluxes, selectivity and membrane potential using liposomes multilabelled with fluorescent probes.
AuthorsVenema K, Gibrat R, Grouzis JP, Grignon C
JournalBiochim Biophys Acta
PubMed ID8382957
Liposomes of egg PC/PG (8:2, mol/mol) were multilabelled with PBFI, pyranine and oxonol VI, fluorescent probes for, respectively, K+, H+ and membrane potential. Monitoring fluorescence with a multichannel photoncounting spectrofluorometer during K+ filling experiments allowed to measure K+ influx, the associated H+ efflux and the membrane potential, continuously and simultaneously. ... More
Fluorescence quenching studies on the characterization of energy generated at the NADH:quinone oxidoreductase and quinol oxidase segments of marine bacteria.
AuthorsKim YJ, Mizushima S, Tokuda H
JournalJ Biochem (Tokyo)
PubMed ID1907969
Generation of membrane potential (inside-positive) and delta pH (inside-acidic) at two kinds of NADH:quinone oxidoreductase segments, the Na(+)-motive segment and another segment, of Vibrio alginolyticus was examined by monitoring the quenching of fluorescence of oxonol V and that of quinacrine, respectively, with inside-out membrane vesicles. Transient generation of membrane potential ... More
Inositol 1,4,5-trisphosphate receptor/Ca2+ channel modulatory role of chromogranin A, a Ca2+ storage protein of secretory granules.
AuthorsYoo SH, Jeon CJ
JournalJ Biol Chem
PubMed ID10748130
The secretory granules of neuroendocrine cells, which contain large amounts of Ca(2+) and chromogranins, have been demonstrated to release Ca(2+) in response to inositol 1,4,5-trisphosphate (IP(3)), indicating the IP(3)-sensitive intracellular Ca(2+) store role of secretory granules. In our previous study, chromogranin A (CGA) was shown to interact with several secretory ... More
A mechanism for tamoxifen-mediated inhibition of acidification.
AuthorsChen Y, Schindler M, Simon SM
JournalJ Biol Chem
PubMed ID10373441
Tamoxifen has been reported to inhibit acidification of cytoplasmic organelles in mammalian cells. Here, the mechanism of this inhibition is investigated using in vitro assays on isolated organelles and liposomes. Tamoxifen inhibited ATP-dependent acidification in organelles from a variety of sources, including isolated microsomes from mammalian cells, vacuoles from Saccharomyces ... More
Use of oxonol V as a probe of membrane potential in proteoliposomes containing cytochrome oxidase in the submitochondrial orientation.
AuthorsCooper CE, Bruce D, Nicholls P
JournalBiochemistry
PubMed ID2162199
Absorbance changes in the anionic dye bis[3-phenyl-5-oxoisoxazol-4-yl]pentamethineoxonol (oxonol V) can be used to monitor the membrane potential of liposomes and cytochrome c containing cytochrome oxidase proteoliposomes (c-loaded COV). Diffusion potentials (positive inside the vesicles) cause an increase in the dye extinction, with a maximum at 640 nm. A similar increase ... More
Electrogenic H+ translocation by the plasma membrane ATPase of Neurospora. Studies on plasma membrane vesicles and reconstituted enzyme.
Fluorescent probes have been used to measure electrogenic proton pumping by the plasma membrane ATPase of Neurospora. In isolated plasma membrane vesicles, greater than 85% of which are inverted, ATP hydrolysis is accompanied by the formation of an inside acid pH gradient (delta pH) which can be detected by acridine ... More
The behavior of the fluorescence lifetime and polarization of oxonol potential-sensitive extrinsic probes in solution and in beef heart submitochondrial particles.
AuthorsSmith JC, Hallidy L, Topp MR
JournalJ Membr Biol
PubMed ID7253009
The fluorescence polarization and lifetime of the extrinsic potential-sensitive probes oxonols V and VI have been investigated both for the dyes free in aqueous and ethanol solutions and in the presence of beef heart submitochondrial particles under resting and energy-transducing conditions. The emission lifetime of the dyes appears to be ... More
Lipopolysaccharide priming of human neutrophils for an enhanced respiratory burst. Role of intracellular free calcium.
Lipopolysaccharide (LPS) pretreatment "primes" neutrophils to release increased amounts of superoxide anion (O2-) when stimulated. We investigated the molecular basis of this enhanced activity. Comparison of kinetic parameters of the respiratory burst NADPH oxidase in unstimulated LPS-primed and control neutrophils disclosed a similar Km for NADPH and no difference was ... More
Studies of the mechanism of activation of HIT-T15 cells by lactate.
AuthorsLynch AM, Trebilcock R, Tomlinson S, Best L
JournalBiochim Biophys Acta
PubMed ID1995073
L-Lactate, D-lactate, propionate and acetate (all 20 mM) caused a marked intracellular acidification in HIT-T15 cells loaded with 2'7'-bis(carboxyethyl)-5'(6')-carboxyfluorescein (BCECF), followed by recovery to more alkaline values. The effects of L- and D-lactate, but not propionate or acetate, were inhibited by 5 mM alpha-fluorocinnamate. Both L- and D-lactate caused a ... More
Synthesis, structure determination, spectral properties, and energy-linked spectral responses of the extrinsic probe oxonol V in membranes.
AuthorsSmith JC, Russ P, Cooperman BS, Chance B
JournalBiochemistry
PubMed ID990268
The direct synthesis of bis]3-phenyl-5-oxoisoxazol-4-yl]pentamethineoxonol, which is shown to be the fluorescent probe OX-V (formerly MC-V), is described. The emission lifetime (0.9 +/- 0.1 ns) and the spectral properties of this dye in a number of systems are presented as well as the relative polarizations associated with the transition moments ... More
Inositol trisphosphate-dependent and -independent Ca2+ mobilization pathways at the vacuolar membrane of Candida albicans.
AuthorsCalvert CM, Sanders D
JournalJ Biol Chem
PubMed ID7706267
Vacuolar membrane vesicles were isolated from Candida albicans protoplasts, and marker enzyme assays were employed to identify the membranes as vacuolar in origin. The mechanisms of Ca2+ uptake and Ca2+ release at the vacuolar membrane were investigated. Ca2+ accumulation by vacuolar membrane vesicles can be generated via H+/Ca2+ antiport. The ... More
Variable selection and multivariate methods for the identification of microorganisms by flow cytometry.
AuthorsDavey HM, Jones A, Shaw AD, Kell DB
JournalCytometry
PubMed ID10554172
BACKGROUND: When exploited fully, flow cytometry can be used to provide multiparametric data for each cell in the sample of interest. While this makes flow cytometry a powerful technique for discriminating between different cell types, the data can be difficult to interpret. Traditionally, dual-parameter plots are used to visualize flow ... More
The adenine nucleotide translocase modulates oligomycin-induced quenching of pyranine fluorescence in submitochondrial particles.
AuthorsZiegler M, Penefsky HS
JournalJ Biol Chem
PubMed ID8244963
Incorporation of the fluorescent, nonpermeant pH indicator pyranine into submitochondrial particles (pyranine-SMP) permitted monitoring of intravesicular pH changes brought about by proton translocation due to oxidation of respiratory chain substrates or to hydrolysis of ATP. Addition of oligomycin to beef heart pyranine-SMP was followed by a pH-independent quenching of pyranine ... More
Inhibition by linoleic acid hydroperoxide of alveolar macrophage superoxide production: effects upon mitochondrial and plasma membrane potentials.
AuthorsForman HJ, Kim E
JournalArch Biochem Biophys
PubMed ID2552924
Linoleic acid hydroperoxide (LOOH) is a naturally occurring product of lipid peroxidation. Incubation of rat alveolar macrophages with LOOH produced alterations of membrane properties and function at concentrations of LOOH as low as 0.1 microM. These included phorbol myristate acetate (PMA)-stimulated superoxide production, mitochondrial membrane potential, and plasma membrane potentials. ... More
Positively charged cyclic hexapeptides, novel blockers for the cardiac sarcolemma Na(+)-Ca2+ exchanger.
AuthorsKhananshvili D, Shaulov G, Weil-Maslansky E, Baazov D
JournalJ Biol Chem
PubMed ID7608184
Positively charged cyclic hexapeptides have been synthesized and tested for their effects on the cardiac sarcolemma Na(+)-Ca2+ exchange activities with a goal to identify a potent blocker. The cyclic hexapeptides, having the different amino acid sequence, contain two arginines (to retain a positive charge), two phenylalanines (to control hydrophobicity), and ... More
Identification and characterization of ATP-dependent proton transport by rat liver multivesicular bodies.
Multivesicular bodies (MVB), prelysosomal organelles in the endocytic pathway, were prepared from estrogen-treated rat livers and examined for the presence of ATP-dependent proton transport. Vesicle acidification, assessed by acridine orange fluorescence quenching, was ATP dependent (ATP much greater than GTP, UTP), was enriched 25-fold over homogenate, was abolished by pretreatment ... More
Vesicular L-glutamate transporter in microvesicles from bovine pineal glands. Driving force, mechanism of chloride anion activation, and substrate specificity.
AuthorsMoriyama Y, Yamamoto A
JournalJ Biol Chem
PubMed ID7673214
Pinealocytes, endocrine cells that synthesize and secrete melatonin, possess a large number of synaptic-like microvesicles (MVs) containing the L-glutamate transporter (Moriyama, Y., and Yamamoto, A. (1995) FEBS Lett., 367, 233-236). In this study, the L-glutamate transporter in MVs isolated from bovine pineal glands was characterized as to its driving force, ... More
Time-resolved monitoring of electrogenic Na+-Ca2+ exchange in the isolated cardiac sarcolemma vesicles by using a rapid-response fluorescent probe.
AuthorsBaazov D, Wang X, Khananshvili D
JournalBiochemistry
PubMed ID9931008
As a major Ca exit system in myocytes, the electrogenic Na+-Ca2+ exchange is exposed to rapid changes of regulatory factors (e.g., cytosolic Ca) during the excitation-contraction coupling. The dynamic aspects of the exchanger response to regulatory factors have not been resolved in the past due to technical limitations. Here, we ... More
Anion inhibition of the proton pump in rat liver multivesicular bodies.
AuthorsVan Dyke RW
JournalJ Biol Chem
PubMed ID3023335
Rat liver multivesicular bodies (MVB), as well as other hepatic subcellular organelles, are acidified by an electrogenic ATP-dependent proton pump that requires Cl- for maximal acidification (Van Dyke, R. W., Hornick, C. A., Belcher, J., Scharschmidt, B. F., and Havel, R.J. (1985) J. Biol. Chem. 260, 11021-11026), suggesting that Cl- ... More
Glutamate transport into synaptic vesicles. Roles of membrane potential, pH gradient, and intravesicular pH.
AuthorsTabb JS, Kish PE, Van Dyke R, Ueda T
JournalJ Biol Chem
PubMed ID1353494
Glutamate, the major excitatory neurotransmitter in the mammalian central nervous system, is transported into bovine synaptic vesicles in a manner that is ATP dependent and requires a vesicular electrochemical proton gradient. We studied the electrical and chemical elements of this driving force and evaluated the effects of chloride on transport. ... More
The interaction of the potential-sensitive molecular probe merocyanine 540 with phosphorylating beef heart submitochondrial particles under equilibrium and time-resolved conditions.
AuthorsSmith JC, Graves JM, Williamson M
JournalArch Biochem Biophys
PubMed ID6732242
The interaction of the potential-sensitive extrinsic molecular probe merocyanine 540 ( M540 ) with phosphorylating submitochondrial particles has been investigated under equilibrium and time-resolved conditions. The addition of ATP to a M540 -membrane suspension produces oligomycin and CCCP-sensitive spectral changes with absolute maxima near 490, 530, and 565 nm; a ... More
Slow fluorescent indicators of membrane potential: a survey of different approaches to probe response analysis.
AuthorsPlásek J, Sigler K
JournalJ Photochem Photobiol B
PubMed ID8691353
Basic tenets related to the use of three main classes of potentiometric redistribution fluorescent dyes (carbocyanines, oxonols, and rhodamines) are discussed in detail. They include the structure/function relationship, formation of nonfluorescent (H-type) and fluorescent (J-type) dimers and higher aggregates, probe partitioning between membranes and medium and binding to membranes and ... More
Regulation of glutamate transport into synaptic vesicles by chloride and proton gradient.
AuthorsWolosker H, de Souza DO, de Meis L
JournalJ Biol Chem
PubMed ID8662610
Glutamate uptake into synaptic vesicles is driven by an electrochemical proton gradient formed across the membrane by a vacuolar H+-ATPase. Chloride has a biphasic effect on glutamate transport, which it activates at low concentrations (2-8 mM) and inhibits at high concentrations (>20 mM). Stimulation with 4 mM chloride was due ... More
Structure and vectorial properties of proteoliposomes containing cytochrome oxidase in the submitochondrial orientation.
AuthorsCooper CE, Nicholls P
JournalBiochemistry
PubMed ID2162200
Cytochrome oxidase proteoliposomes were prepared from bovine heart oxidase. Size distributions determined by quasi-elastic light scattering (QELS) showed that there was a small population of large vesicles (120-200-nm diameter) and a large population of small vesicles (50-100-nm diameter). Trapping cytochrome c inside the proteoliposomes did not significantly alter this size ... More
Regulation of vacuolar Na+/H+ exchange in Arabidopsis thaliana by the salt-overly-sensitive (SOS) pathway.
AuthorsQiu QS, Guo Y, Quintero FJ, Pardo JM, Schumaker KS, Zhu JK
JournalJ Biol Chem
PubMed ID14570921
For plants growing in highly saline environments, accumulation of sodium in the cell cytoplasm leads to disruption of metabolic processes and reduced growth. Maintaining low levels of cytoplasmic sodium requires the coordinate regulation of transport proteins on numerous cellular membranes. Our previous studies have linked components of the Salt-Overly-Sensitive pathway ... More
The interaction of potential-sensitive molecular probes with dimyristoylphosphatidylcholine vesicles investigated by 31P-NMR and electron microscopy.
AuthorsBammel BP, Brand JA, Simmons RB, Evans D, Smith JC
JournalBiochim Biophys Acta
PubMed ID3801465
The effect of a number of commonly employed potential-sensitive molecular probes on the 31P-NMR properties of dimyristoylphosphatidylcholine vesicles at two field strengths has been investigated in order to obtain information on the location and effect of these probes on the membrane bilayer. In comparison to the control dye-free vesicle spectrum, ... More
Reconstitution of transport function of vacuolar H(+)-translocating inorganic pyrophosphatase.
AuthorsBritten CJ, Zhen RG, Kim EJ, Rea PA
JournalJ Biol Chem
PubMed ID1328246
A procedure for reconstitution of the transport function of the vacuolar H(+)-translocating inorganic pyrophosphatase (H(+)-PPase; EC 3.6.1.1) prepared from etiolated hypocotyls of Vigna radiata (mung bean) is described. The method entails sequential extraction of isolated vacuolar membrane (tonoplast) vesicles with deoxycholate and CHAPS (3-[(3-cholamidopropyl)-dimethylammonio]-1-propanesulfonate), combination of CHAPS-solubilized protein with phospholipid-cholesterol ... More
Association of Helicobacter pylori vacuolating toxin (VacA) with lipid rafts.
AuthorsSchraw W, Li Y, McClain MS, van der Goot FG, Cover TL
JournalJ Biol Chem
PubMed ID12121984
A variety of extracellular ligands and pathogens interact with raft domains in the plasma membrane of eukaryotic cells. In this study, we examined the role of lipid rafts and raft-associated glycosylphosphatidylinositol (GPI)-anchored proteins in the process by which Helicobacter pylori vacuolating toxin (VacA) intoxicates cells. We first investigated whether GPI-anchored ... More
Existence of an adenosine 5'-triphosphate dependent proton translocase in bovine neurosecretory granule membrane.
AuthorsScherman D, Nordmann J, Henry JP
JournalBiochemistry
PubMed ID6462172
The addition of ATP to bovine neurohypophysial secretory granules suspended in isotonic sucrose medium induces a positive polarization, delta psi, of their interior without affecting their internal pH. In KCl-containing media, ATP failed to generate large delta psi but induced a pH gradient (delta pH; interior acidic). These observations are ... More
The effect of potential-sensitive molecular probes on the thermal phase transition in dimyristoylphosphatidylcholine preparations.
AuthorsFumero J, Bammel BP, Hopkins HP, Smith JC
JournalBiochim Biophys Acta
PubMed ID3179288
Differential scanning calorimetry (DSC) has been employed to determine the effect of five commonly employed extrinsic potential-sensitive probes on phase transitions of multilamellar suspensions of L-alpha-dimyristoylphosphatidylcholine (DMPC). At mol% values of less than five, the effect of these probes on the excess heat capacity curve in the vicinity of the ... More
A vacuolar-type proton pump in a vesicle fraction enriched with potassium transporting plasma membranes from tobacco hornworm midgut.
AuthorsWieczorek H, Weerth S, Schindlbeck M, Klein U
JournalJ Biol Chem
PubMed ID2472389
Mg-ATP dependent electrogenic proton transport, monitored with fluorescent acridine orange, 9-aminoacridine, and oxonol V, was investigated in a fraction enriched with potassium transporting goblet cell apical membranes of Manduca sexta larval midgut. Proton transport and the ATPase activity from the goblet cell apical membrane exhibited similar substrate specificity and inhibitor ... More
ATP-dependent proton transport by isolated brain clathrin-coated vesicles. Role of clathrin and other determinants of acidification.
AuthorsVan Dyke RW, Scharschmidt BF, Steer CJ
JournalBiochim Biophys Acta
PubMed ID2857093
We have systematically investigated certain characteristics of the ATP-dependent proton transport mechanism of bovine brain clathrin-coated vesicles. H+ transport specific activity was shown by column chromatograpy to co-purify with coated vesicles, however, the clathrin coat is not required for vesicle acidification as H+ transport was not altered by prior removal ... More