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7 Fluctuations of the Proton Electromotive Force Across Inner Mitochondrial. . .
7.8 Program 7.1, Fluctuations of the PMF, Matlab Code
% Fluctuational Domain size = 30 (nm)
%—–Assumes that TauBuffer = TauMembrane and calculates Racces
Nsteps = 700; N=Nsteps; w=(1:N)*0; PMFsqw=(1:N)*0;
RT = 2493;
kT = 4.143E-21; avogadro = 6.02E+23; faraday = 96500; pi = 3.1416;
electron = 1.602E-19; epszero = 8.85E-12; eps = 2; integral=0.;
diff = 1.E-07; % Diffusion coefficient of proton in m2/sec = 1 x 10-8
d = 7E-09; %Membrane width in meters
cubeside = 1.9E-08; % = Cube side in meters = intermembrane space
memarea = cubeside 2 %Membrane Area patch in m2
cubevolume = cubeside 3 ; %Cube volume in m3
Beta = 10; %Buffering capacitance – 10 Moles of acid added
%in 1 m3 = 1 unit change in pH
%From Lauger (Electrogenic ion pumps)
pH = 7.4; molarm3 = (10 ( − pH )) * 1000; %Concentration of protons in moles/m3
protonsm3 = molarm3 * avogadro; %Num. of protons/m3
numproton = cubevolume * protonsm3 ; %Number of protons in the cube
SCC = (molarm3 / (.000063)) * (1E-12); %Lauger, at pH aprox. = 7.2
%—-SCC is the single-channel cond. of the pump normalized for the given pH
Rm = 1 / SCC %Resistance of membrane patch in ohms
Cm = eps * epszero * (memarea / d)
Taum = Rm * Cm % seconds
Taubuff = Taum %Assumes that Taubuff = Taum
Cbuffer = (Beta * cubevolume * faraday * faraday) / (2.3 * RT)
Raccess = Taubuff / Cbuffer
%————-Frequencias inicial e final em Hz —–
freqinicial = .001; freqfinal = 1.E+06;
freqmedia = (freqfinal - freqinicial) / 2;
omegainicial = freqinicial * 2 * pi;
omegafinal = freqfinal * 2 * pi;
%Nsteps Number of steps in integration
deltaOmega = (omegafinal - omegainicial) / Nsteps %Pass of integration
di=1;
i=1;
for omega = omegainicial : deltaOmega : omegafinal
i=i+di;
frequency = omega / (2 * pi);
Domega1 = ((omega * Rm * Taum) / (1 + (omega * Taum) 2 )) + (Raccess / (omega
* Taubuff));
Domega2 = (Rm / (1 + (omega * Taum) 2 )) + Raccess;
domega = (Domega1 2 ) + (Domega2 2 ); %Eq. (7.8)
alfa1A = (omega * Rm * Taum) / (1 + (omega * Taum) 2 );
7 Fluctuations of the Proton Electromotive Force Across Inner Mitochondrial. . .
7.8 Program 7.1, Fluctuations of the PMF, Matlab Code
% Fluctuational Domain size = 30 (nm)
%—–Assumes that TauBuffer = TauMembrane and calculates Racces
Nsteps = 700; N=Nsteps; w=(1:N)*0; PMFsqw=(1:N)*0;
RT = 2493;
kT = 4.143E-21; avogadro = 6.02E+23; faraday = 96500; pi = 3.1416;
electron = 1.602E-19; epszero = 8.85E-12; eps = 2; integral=0.;
diff = 1.E-07; % Diffusion coefficient of proton in m2/sec = 1 x 10-8
d = 7E-09; %Membrane width in meters
cubeside = 1.9E-08; % = Cube side in meters = intermembrane space
memarea = cubeside 2 %Membrane Area patch in m2
cubevolume = cubeside 3 ; %Cube volume in m3
Beta = 10; %Buffering capacitance – 10 Moles of acid added
%in 1 m3 = 1 unit change in pH
%From Lauger (Electrogenic ion pumps)
pH = 7.4; molarm3 = (10 ( − pH )) * 1000; %Concentration of protons in moles/m3
protonsm3 = molarm3 * avogadro; %Num. of protons/m3
numproton = cubevolume * protonsm3 ; %Number of protons in the cube
SCC = (molarm3 / (.000063)) * (1E-12); %Lauger, at pH aprox. = 7.2
%—-SCC is the single-channel cond. of the pump normalized for the given pH
Rm = 1 / SCC %Resistance of membrane patch in ohms
Cm = eps * epszero * (memarea / d)
Taum = Rm * Cm % seconds
Taubuff = Taum %Assumes that Taubuff = Taum
Cbuffer = (Beta * cubevolume * faraday * faraday) / (2.3 * RT)
Raccess = Taubuff / Cbuffer
%————-Frequencias inicial e final em Hz —–
freqinicial = .001; freqfinal = 1.E+06;
freqmedia = (freqfinal - freqinicial) / 2;
omegainicial = freqinicial * 2 * pi;
omegafinal = freqfinal * 2 * pi;
%Nsteps Number of steps in integration
deltaOmega = (omegafinal - omegainicial) / Nsteps %Pass of integration
di=1;
i=1;
for omega = omegainicial : deltaOmega : omegafinal
i=i+di;
frequency = omega / (2 * pi);
Domega1 = ((omega * Rm * Taum) / (1 + (omega * Taum) 2 )) + (Raccess / (omega
* Taubuff));
Domega2 = (Rm / (1 + (omega * Taum) 2 )) + Raccess;
domega = (Domega1 2 ) + (Domega2 2 ); %Eq. (7.8)
alfa1A = (omega * Rm * Taum) / (1 + (omega * Taum) 2 );