Oxygen diffusion-concentration in erythrocyte plasma membranes studied by the fluorescence quenching of anionic and cationic pyrene derivatives

Abstract

Fluorescence quenching by oxygen of cationic [pyrene-(CH2)nN(CH3)3+; n = 1, 4, and 11] and anionic [pyrene-(CH2)nCO2-, n = 3, 8, 11, and 15] probes was investigated in erythrocyte plasma membranes (leaky) in order to assess the ability of oxygen molecules to interact with solutes located at different positions in the membrane. The pseudounimolecular quenching rate constants measured increase, both for cationic and anionic probes, when n increases. These results are interpreted in terms of an increased oxygen solubility toward the center of the membrane interior, and imply that lateral diffusion contributes more than transverse diffusion to total oxygen mobility. For all of the probes considered, quenching rates increase when n-alkanols are added. The effect observed increases when n decreases and when the size of the n-alkanol alkyl chain increases. Arrhenius-type plots for the quenching rate constants show noticeable downward curvatures. Average (0-40 degrees C) activation energies are approximately 6 kcal/mol.

Direct Measurement of Nitric Oxide and Oxygen Partitioning into Liposomes and Low Density Lipoprotein

“…This value accounts for the entire bilayer, including polar phosphocholine headgroups. However, there is evidence indicating that O 2 , ⅐ NO, and other apolar molecules, are less favorably dissolved in this region of the membrane (33)(34)(35)40) and should therefore be excluded from the hydrophobic volume. We assumed a 0.75 bilayer hydrophobic fraction, thus the corrected K P from Smotkin et al (37) would be 4.9 Ϯ 0.8, which is in agreement within experimental errors with that found by ourselves (Table I).…”

Effect of Adriamycin treatment on the lifetime of pyrene butyric acid in single living cells

“…It is nowadays used for membrane fluidity detection [3] and oxygen sensing film [4]. Other pyrene derivatives allow measurement of oxygen concentrations in living cells by the detection of fluorescence intensity variations [5,6] or fluorescence lifetime changes [7]. Lifetime measurements are not dependent on the absolute intensity of the emitted light and, therefore, independent of the probe concentration.…”

Oxygen‐mediated cold‐acclimation in cucumber (Cucumis sativus) seedlings

“…Because acclimation‐induced increase in fatty acid desaturation (Fig. 3) leads to membrane fluidization (Thompson 1979), and an accompanying stimulation in cross‐membrane gas permeability (Zander 1976, Lissi and Caceres 1989), we examined whether acclimation may also enhance respiratory gas exchange. The results revealed that in acclimated cucumber seedlings (48 h at 12°C) there was a respiratory upsurge during the follow‐up warming period (Fig.…”

“…Cross-membrane permeability constrains oxygen diffusion to the cellular interior (Grinberg et al 1998) and this process is restrained further by chilling-induced membrane-lipid rigidification (Dumas et al 1997). Because acclimation-induced lipid re-tailoring leads to membrane-lipid fluidization (Thompson 1979(Thompson , 1983 and because membranelipid fluidity enhances gas permeability (Zander 1976, Lissi andCaceres 1989), we reasoned that cold acclimation might also lead to enhanced respiratory gas exchange in cucumber seedlings. The results show, accordingly, a higher respiratory gas exchange in acclimated compared with non-acclimated cucumber seedlings (Fig.…”

“…1997). Because acclimation‐induced lipid re‐tailoring leads to membrane‐lipid fluidization (Thompson 1979, 1983) and because membrane‐lipid fluidity enhances gas permeability (Zander 1976, Lissi and Caceres 1989), we reasoned that cold acclimation might also lead to enhanced respiratory gas exchange in cucumber seedlings. The results show, accordingly, a higher respiratory gas exchange in acclimated compared with non‐acclimated cucumber seedlings (Fig.…”