BCH4024 - Allen Lecture 27 - 28

BCH4024 - Allen Lecture 27 - 28 - Electron Transport and...

Info iconThis preview shows pages 1–7. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Electron Transport and Oxidative Phosphorylation Acetyl CoA Production Acetyl CoA Oxidation Electron Transfer p 602 Lehn p 691 Lehn This process is the mechanism by which cells convert the energy stored in reduced cofactors, NADH and FADH 2 into ATP. The electron transport system (ETS) consists of complexes containing about 44 polypeptides and 1 lipid (Coenzyme Q) and involves the transfer of reducing equivalents (hydride ions, hydrogen atoms or electrons) from the reduced cofactors to molecular O 2 . Electrons flow uni-directionally along an energy gradient; electrons move from a carrier of high reducing potential (i.e. greater tendency to donate electrons) toward a carrier with greater oxidizing potential ( i.e. greater tendency to accept electrons), successively through several carriers to O 2 . For example XH 2 NAD + carrier 1 red carrier 2 ox H 2 O X NADH carrier 1 ox carrier 2 red O 2 The energy drop from NADH E o ' = - 0.32 V to O 2 E o ' = +0.82 V E o ' = +1.14 V This corresponds to a free energy change of G o = -nF E o ' = -220 kJ/mole Since the G o ' for each ATP is -30.5 kJ/mole, this potential drop is sufficient for the synthesis of several ATPs due to the reduction of O 2 by NADH. Practically it appears that a maximum of 3 ATP can be synthesized for each pair of electrons transported. Our discussion will center on the character of the ETS and the coupling of electron transport with the synthesis of ATP. Key Constituents of the Electron Transport System Cytochromes b,c,c 1 , a, and a 3 are proteins containing heme (protoporphyrin) rings that have Fe bound to them. The iron undergoes reversible oxidation and reduction....
View Full Document

This note was uploaded on 03/15/2010 for the course BCH 4024 taught by Professor Allison during the Spring '08 term at University of Florida.

Page1 / 31

BCH4024 - Allen Lecture 27 - 28 - Electron Transport and...

This preview shows document pages 1 - 7. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online