Simulations of the active transport of a neutral solute based on a kinase-channel-phosphatase topology.
Simulations of coupled interactions involving two opposite enzymatic reactions, solute diffusions, and electrostatic interactions between membrane charges and charged solutes were conducted under a fixed kinase-channel-phosphatase (KCP) topology oriented from the outside to the inside of a porous membrane structure. Depending on the kinase and phosphatase locations, we recently demonstrated that an active transport of a phosphorylated substrate may occur via the opposite topology, that is, a PCK topology. The present analysis demonstrates that, under a KCP membrane topology, which also behaves as a specific ATP-dependent transporter, the active transport of a neutral substrate may occur. This analogous active transport appears to be dependent on the phosphatase location and on the membrane surface potentials. A broad analysis of the role played by the main parameters taken into account in the model was conducted in order to define precisely the physico-chemical conditions and the membrane topology needed for the highest active transports within the shortest time.
Fiaty
K
K
Laboratoire d'Automatique et de Génie des Procédés, UMR-CNRS 5007, CPE Lyon, Université Claude Bernard Lyon 1, Bat 308 G, 43 Bd du 11 novembre 1918, 69622 Villeurbanne cedex, France.
Charcosset
C
C
Perrin
B
B
Couturier
R
R
Maïsterrena
B
B
D001693:Biological Transport, Active; D003198:Computer Simulation; D007473:Ion Channels / Q000737:chemistry* / Q000378:metabolism; D008564:Membrane Potentials; D008954:Models, Biological; D010744:Phosphoric Monoester Hydrolases / Q000737:chemistry* / Q000378:metabolism; D010770:Phosphotransferases / Q000737:chemistry* / Q000378:metabolism
D007473:Ion Channels; D010770:Phosphotransferases; D010744:Phosphoric Monoester Hydrolases