BIOL 3510 1st Edition Lecture 14 Outline of Last Lecture I Terms of Metabolism II Stages of Metabolism III Glycolysis IV The Citric Acid Cycle Outline of Current Lecture I Parts of the Mitochondria II Types of Electron Carriers III Oxidation Current Lecture Parts of the Mitochondria Outer membrane contains porin which forms large channels Intermembrane space contains many of the same molecules as the cytosol Innermembrane impermeable to ions and most molecules contains electron transport chain proteins forms cristae Matrix contains molecules selectively transported across the inner membrane Oxidative Phosphorylation is a chemiosmotic process Oxidative phosphorylation of ADP to create ATP using energy derived from the transfer of electrons to oxygen Chemiosmotic coupling is where the pH gradient drives an energy requiring process As electrons are transferred through three enzyme complexes H are transported to the intermembrane NADH donates electrons to the NADH dehydrogenase complex Types of Electron Carriers 1 Quinone ubiquinone in mitochondria small hydrophobic molecule that diffuses within the lipid bilayer accept 1 or 2 e from NADH or FADH2 2 Iron sulfur centers contains iron and sulfur molecules and are covalently attached to iron sulfur proteins Hold 1 e 3 Heme groups contain iron molecules and are covalently attached to cytochrome proteins hold 1 e These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute Electron Transfer Results in H Pumping Using Distinct Mechanisms 1 During reduction and oxidation electron carriers pick up an H on one side of the membrane and release it on the other 2 Electron Transport leads to sequential conformation changes that causes a protein to pump protons Cytochrome oxidase catalyzes the reduction of O2 to H2O coordinates the addition of 4e to 1 O2 The H gradient generated by the e transport chain is used to generate ATP Proton pumping generates a pH gradient and membrane potential across the inner membrane Proton pumping generates a pH gradient and membrane potential across the inner membrane ATP synthase uses protons flowing into the matrix to generate ATP and is reversible The H gradient and membrane potential area also used to transport molecules across the inner membrane of the mitochondria Pyruvate H and Pi H synporters move pyruvate and Pi into the matrix ADP and ATP are exchanged via an anti porter driven by the membrane potential Oxidation of one glucose molecule produces 30 ATP molecules Mitochondrial genomes and ribosomes are located in the matrix Mitochondrial and chloroplasts contain proteins encoded by nuclear and organelle genomes Mitochondrial encoded proteins and nuclear encoded proteins work together to accomplish mitochondrial functions They are dynamic they divide fuse and change shape
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