Estimation of membrane potential deltapsi in reconstituted plasma membrane vesicles using a numerical model of oxonol VI distribution.
A model of membrane potential-dependent distribution of oxonol VI to estimate the electrical potential difference deltapsi across Schizosaccharomyces pombe plasma membrane vesicles (PMV) has been developed. deltapsi was generated by the H+-ATPase reconstituted in the PMV. The model treatment was necessary since the usual calibration of the dye fluorescence changes by diffusion potentials (K+ + valinomycin) failed. The model allows for fitting of fluorescence changes at different vesicle and dye concentrations, yielding deltapsi in ATP-energized PMV of 80 mV. The described model treatment to estimate deltapsi may be applicable for other reconstituted membrane systems.
Portele
A
A
Botanisches Institut, Universität Bonn, Germany.
Lenz
J
J
Höfer
M
M
D002462:Cell Membrane; D005456:Fluorescent Dyes / Q000378:metabolism*; D007555:Isoxazoles / Q000378:metabolism*; D008564:Membrane Potentials; D008954:Models, Biological; D015233:Models, Statistical; D012568:Schizosaccharomyces / Q000502:physiology*
D005456:Fluorescent Dyes; D007555:Isoxazoles; C031184:oxonol VI