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Tuyển tập các báo cáo nghiên cứu khoa học ngành y học tạp chí Medical Sciences dành cho các bạn sinh viên ngành y tham khảo đề tài: OXIDATIVE PHOSPHORYLATION: Kinetic and Thermodynamic Correlation between Electron Flow, Proton Translocation, Oxygen Consumption and ATP Synthesis under Close to In Vivo Concentrations of Oxygen. | Int. J. Med. Sci. 2008 5 143 Research Paper International Journal of Medical Sciences ISSN 1449-1907 www.medsci.org 2008 5 3 143-151 Ivyspring International Publisher. All rights reserved OXIDATIVE PHOSPHORYLATION Kinetic and Thermodynamic Correlation between Electron Flow Proton Translocation Oxygen Consumption and ATP Synthesis under Close to In Vivo Concentrations of Oxygen Baltazar D. Reynafarje1 and Jorge Ferreira2 1. Johns Hopkins University School of Medicine Department of Biological Chemistry Baltimore Maryland 21205 USA. 2. Programa de Farmacología Molecular y Clínica Facultad de Medicina Universidad de Chile Independencia 1027 Casilla 70000 Santiago-7 Chile. Correspondence to Jorge Ferreira Programa de Farmacología Molecular y Clínica Facultad de Medicina Universidad de Chile Independencia 1027 Casilla 70000 Santiago-7 Chile. E-mail jferreir@med.uchile.cl Fax 56 2 735 5580 Tel 56 2 978 6069. Received 2008.04.15 Accepted 2008.06.05 Published 2008.06.09 For the fist time the mitochondrialprocess of oxidative phosphorylation has been studied by determining the extent and initial rates of electron flow H translocation O2 Uptake and ATP synthesis under close to in vivo concentrations of oxygen. The following novel results were obtained. 1 The real rates of O2 uptake and ATP synthesis are orders of magnitude higher than those observed under state-3 metabolic conditions. 2 The phosphorylative process of ATP synthesis is neither kinetically nor thermodynamically related to the respiratory process of H ejection. 3 The ATP O stoichiometry is not constant but varies depending on all the redoX potential AEh the degree of reduction of the membrane and the relative concentrations of o2 ADP and protein. 4 The free energy ofelectron flow is not only used for the enzymatic binding and release of substrates and products but fundamentally for the actual synthesis of ATP from ADP and Pi. 5 The concentration of ADP that Ễroduces half-maximal responses of ATP synthesis EC50 is
