Computer simulation of cytoplasmic pH regulation mediated by the F-type H+-ATPase.
Cytoplasmic pH regulation mediated by the H(+)-ATPase was examined with the aid of computer simulation. The data obtained with our simulation model were consistent with the experimental data and the simulation clarified the following points that may be difficult to be clarified with experimental studies. (1) The change in the enzyme amount controlled by cytoplasmic pH was essential for the pH regulation. (2) No significant change in internal pH was observed in acidic surroundings even if the proton transport activity of the H(+)-ATPase changed greater than sixfold. (3) The cytoplasmic pH homeostasis can be maintained even when the biosynthetic rate of the enzyme decreased by 50%. These results suggested that this regulatory system has an ability to maintain the pH in homeostasis even under harsh conditions that decrease cellular metabolic activities.
Kobayashi
Hiroshi
H
Graduate School of Pharmaceutical Sciences, Chiba University, 1-33, Yayoi-cho, Inage, Chiba 263-8522, Japan. hiroshi@p.chiba-u.ac.jp
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D003198:Computer Simulation; D006706:Homeostasis; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008954:Models, Biological
D000251:Adenosine Triphosphatases