1-Anilino-8-naphthalenesulfonate: A fluorescent probe of ion and ionophore transport kinetics and trans-membrane asymmetry

Haynes, Duncan H.; Simkowitz, Philip

doi:10.1007/bf01869512

Cited by 70 publications

(41 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results and the transport of calcium in depleted vesicles, suggest some electrogenic nature of calcium uptake. However, the use of ansyl as the probe for measuring membrane potential has been found to be questionable by others [37,38] and the data should be taken with caution.…”

Section: Discussionmentioning

confidence: 99%

Active Transport of Calcium in Membrane Vesicles from Mycobacterium phlei

1979

View full text Add to dashboard Cite

Active transport of calcium ions has been demonstrated in inside-out membrane vesicles from Mycobacterium phlei mediated by respiratory linked substrates as well as by ATP hydrolysis. The uptake of calcium exhibited an apparent K , of 80 pM and V of 16.6 nmol calcium uptake x min-' x mg protein-'. A fortyfold concentration gradient for calcium ions was calculated for both the ATP-induced and the respiration-induced transport of calcium. Removal of coupling-factor-latent ATPase resulted in the complete loss of ATP-driven Ca2+ transport whereas the respiration-driven uptake was reduced by 40-50 %. The uptake of calcium was inhibited by the proton conducting ionophores carbonylcyanide m-chlorophenylhydrazone and Gramicidin-D. The accumulated calcium was freely exchangeable with external calcium and was rapidly released by the addition of inhibitors of energy transduction, proton-translocating uncouplers or the ionophore A231 87. The uptake of the weak base, methylamine, upon the oxidation of respiratory-linked substrates or the hydrolysis of ATP showed the generation of a proton gradient (inside acidic) which was partially collapsed on the addition of calcium ions. These results suggest that a Ca2+/H+ antiport mechanism may be responsible for the transport of calcium.Electron transport particles prepared by the sonication of Mycobacteriurnphlei cells, are capable of oxidation with succinate or NAD+-linked substrates [I] and also exhibit phosphorylation coupled to the substrate oxidation. However, removal of coupling-factor-latent ATPase from the membrane vesicles by washing with 0.25 M sucrose, results in the formation of depleted vesicles which exhibit only substrate oxidation but no coupled phosphorylation [2,3]. The latent ATPase is activated by trypsin treatment and requires the presence of Mg2+ for the expression of its ATPase activity [4,5]. Unlike membrane-bound ATPase from Escherichiu coli [6] and Micrococcus lysodeikiticus [7], the M . phlei latent ATPase did not show any calciumstimulated ATPase activity [4]. Therefore, it was of interest to ascertain whether in spite of this, the membrane vesicles from M . phlei are capable of transportThis paper is dedicated to the 80th Birthday of Dr Fritz Lipmann.Abbreviations and Trivial Names. Membrane vesicles, electron transport particles; depleted vesicles, electron transport particles depleted of coupling-factor-latent ATPase; Hepes, 4-(2-hydroxyethyl)-l-piperazineethanesulfonic acid; ansyl, 8-aninlino-l-naphthalenesulfonic acid; Ph (NMez)2,N,N,N',N'-tetrarnethyl-p- [12]. It was also found desirable to study the mechanism of calcium transport and its effect on oxidative phosphorylation in M . phlei membrane vesicles.The present communication described the properties and characteristics of calcium transport in M . phlei membrane vesicles. It has been demonstrated that the oxidation of the respiratory-linked substrates or the hydrolysis of ATP generate a proton gradient of approximately 2.0 pH units across the membrane (inside acidic) which presumably provides th...

show abstract

Section: Discussionmentioning

confidence: 99%

Active Transport of Calcium in Membrane Vesicles from Mycobacterium phlei

1979

View full text Add to dashboard Cite

show abstract

“…These findings were rationalized in terms of the positive dipole potential in the region between the aqueous phase and interior of the membrane bilayer [43,44]. Regardless of whether or not these observations are broadly representative, the charged form of both anionic and cationic IOCs can be associated with counter-ions in the aqueous phase and therefore transport as an ion pair may be a more important consideration [45,46]. An additional uptake pathway for cationic substances in association with anionic phospholipids has also been proposed and included in a theoretical passive absorption model of the human gastrointestinal tract (GIT) [47].…”

Section: Absorptionmentioning

confidence: 93%

Development and evaluation of a mechanistic bioconcentration model for ionogenic organic chemicals in fish

Armitage

Arnot

Wania

et al. 2012

Enviro Toxic and Chemistry

159

241

View full text Add to dashboard Cite

Abstract-A mechanistic mass balance bioconcentration model is developed and parameterized for ionogenic organic chemicals (IOCs) in fish and evaluated against a compilation of empirical bioconcentration factors (BCFs). The model is subsequently applied to a set of perfluoroalkyl acids. Key aspects of model development include revised methods to estimate the chemical absorption efficiency of IOCs at the respiratory surface (E W ) and the use of distribution ratios to characterize the overall sorption capacity of the organism. Membranewater distribution ratios (D MW ) are used to characterize sorption to phospholipids instead of only considering the octanol-water distribution ratio (D OW ). Modeled BCFs are well correlated with the observations (e.g., r 2 ¼ 0.68 and 0.75 for organic acids and bases, respectively) and accurate to within a factor of three on average. Model prediction errors appear to be largely the result of uncertainties in the biotransformation rate constant (k M ) estimates and the generic approaches for estimating sorption capacity (e.g., D MW ). Model performance for the set of perfluoroalkyl acids considered is highly dependent on the input parameters describing hydrophobicity (i.e., log K OW of the neutral form). The model applications broadly support the hypothesis that phospholipids contribute substantially to the sorption capacity of fish, particularly for compounds that exhibit a high degree of ionization at biologically relevant pH. Additional empirical data on biotransformation and sorption to phospholipids and subsequent incorporation into property estimation approaches (e.g., k M , D MW ) are priorities with respect to improving model performance. Environ. Toxicol. Chem. 2013;32:115-128. # 2012 SETAC

show abstract

“…This indirect approach was adopted after finding other ionophore calibration methods unsuitable. Negatively charged dyes are known to interact with valinomycin-K + complexes (Gains and Dawson, 1975;Haynes and Simkowitz, 1977), resulting in enhanced fluorescence signals from dye present in hydrophobic environments. Such interactions have been reported for the two dyes used in this study (Russel et al, 1979;Tsien et al, 1982a) and were confirmed in preliminary experiments.…”

Section: Calibration Of Oxonol Fluorescence Signalsmentioning

confidence: 99%

Lymphocyte membrane potential and Ca²⁺‐sensitive potassium channels described by oxonol dye fluorescence measurements

Wilson

Chused

1985

Journal Cellular Physiology

170

View full text Add to dashboard Cite

A method is described for quantitative measurement of lymphocyte transmembrane electrical potential difference (psi) by flow cytometric recording of the oxonol dye fluorescence of single cells. Both the simultaneous collection and analysis of multiple optical parameters and the use of a negatively charged oxonol probe allowed more accurate measurement of psi than may be obtained by bulk cell suspension techniques employing cationic voltage indicators. Mouse spleen and human blood lymphocyte psi was calculated to be -70 mV. T and B lymphocytes maintain a constant psi as extracellular K+ is varied from 2 to 10 mM and the deviation from K+ equilibrium potentials (EK) is shown to result from Na+ permeability. At [K+]o values greater than 10 mM, lymphocytes behave as K+ electrodes. Examination of lymphocyte subsets showed that hyperpolarization induced by the Ca2+ ionophore A23187 occurs only in T cells. This response was identified as activation of a Ca2+-sensitive K+ channel by pharmacologic manipulations. Hence, T cells depolarized by 4-aminopyridine (4-AP, 10 mM) were observed to return to resting psi by A23187-induced elevation of [Ca2+]i. Cells depolarized by quinine (100 microM) were unaffected by A23187. The Ca2+-activated channel does not contribute to resting psi in T cells since it may be selectively blocked by quinine (20 microM) or modulated by calmodulin antagonists (5 microM trifluperazine) without affecting resting psi.

show abstract

1-Anilino-8-naphthalenesulfonate: A fluorescent probe of ion and ionophore transport kinetics and trans-membrane asymmetry

Cited by 70 publications

References 53 publications

Active Transport of Calcium in Membrane Vesicles from Mycobacterium phlei

Active Transport of Calcium in Membrane Vesicles from Mycobacterium phlei

Development and evaluation of a mechanistic bioconcentration model for ionogenic organic chemicals in fish

Lymphocyte membrane potential and Ca²⁺‐sensitive potassium channels described by oxonol dye fluorescence measurements

Contact Info

Product

Resources

About

1-Anilino-8-naphthalenesulfonate: A fluorescent probe of ion and ionophore transport kinetics and trans-membrane asymmetry

Cited by 70 publications

References 53 publications

Active Transport of Calcium in Membrane Vesicles from Mycobacterium phlei

Active Transport of Calcium in Membrane Vesicles from Mycobacterium phlei

Development and evaluation of a mechanistic bioconcentration model for ionogenic organic chemicals in fish

Lymphocyte membrane potential and Ca2+‐sensitive potassium channels described by oxonol dye fluorescence measurements

Contact Info

Product

Resources

About

Lymphocyte membrane potential and Ca²⁺‐sensitive potassium channels described by oxonol dye fluorescence measurements