Energy dissipation in slipping biological pumps.
We describe active transport in slipping biological pumps, using mesoscopic nonequilibrium thermodynamics. The pump operation is characterised by its stochastic nature and energy dissipation. We show how heating as well as cooling effects can be associated with pump operation. We use as an example the well studied active transport of Ca2+ across a biological membrane by means of its ATPase, and use published data to find values for the transport coefficients of the pump under various conditions. Most of the transport coefficients of the pump, including those that relate ATP hydrolysis or synthesis to thermal effects, are estimated. This can give a quantitative description of thermogenesis. We show by calculation that all of these coupling coefficients are significant.
Kjelstrup
Signe
S
Department of Chemistry, Faculty of Natural Science and Technology, Norwegian University of Science and Technology, Trondheim, 7491, Norway. signekj@phys.chem.ntnu.no
Rubi
J Miguel
JM
Bedeaux
Dick
D
D000251:Adenosine Triphosphatases / Q000737:chemistry; D000255:Adenosine Triphosphate / Q000737:chemistry*; D001692:Biological Transport; D001703:Biophysics / Q000379:methods; D002118:Calcium / Q000737:chemistry*; D002462:Cell Membrane / Q000378:metabolism*; D002627:Chemistry, Physical / Q000379:methods; D019277:Entropy; D006358:Hot Temperature; D006868:Hydrolysis; D007477:Ions; D008956:Models, Chemical; D015233:Models, Statistical; D013269:Stochastic Processes; D013816:Thermodynamics
D007477:Ions; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D002118:Calcium