9 chapter Bioenergetics and Metabolism.pptx BSN

Bioenergetics

1. Bioenergetics and Metabolism Roshan Ali Assistant Professor IBMS, KMU

2. Course contents Definition of Bioenergetics Free Energy Biogenetic Metabolism Biological Oxidation Oxidation Electron transport chain Electron Carriers Biological Redox Reaction Role of ATP in linking Catabolism and Anabolism

3. Bioenergetics Bioenergetics  is the part of biochemistry concerned with the energy involved in making and breaking of chemical bonds in the molecules found in biological organisms. It can also be defined as the study of energy relationships and energy transformations in living organisms . https:// en.wikipedia.org/wiki/Bioenergetics December 9, 2015

4. Free Energy the energy in a physical system that can be converted to do work, in particular:

5. Metabolism Metabolism is a term that is used to describe all chemical reactions involved in maintaining the living state of the cells and the organism. Metabolism can be conveniently divided into two categories: Catabolism - the breakdown of molecules to obtain energy Anabolism - the synthesis of all compounds needed by the cells By Dr Ananya Mandal, MD http:// www.news-medical.net/health/What-is-Metabolism.aspx December 9, 2015

6. Biological Oxidation All reactions which involve electron flow are considered oxidation-reduction reactions. The basic definition can be defined as: One reactant is oxidized (loses electrons), while another is reduced (gains electrons). The flow of electrons is a vital process that provides the necessary energy for the survival of all organisms. The primary source of energy that drives the electron flow in nearly all of these organisms is the radiant energy of the sun, in the form of electromagnetic radiation or Light. Through a series of nuclear reactions, the sun is able to generate thermal energy (which we can feel as warmth) from electromagnetic radiation (which we perceive as light). 

7. Electron transport chain An electron transport chain (ETC) is a series of compounds that transfer electrons from electron donors to electron acceptors via redox reactions, and couples this electron transfer with the transfer of protons (H+ ions) across a membrane . https:// en.wikipedia.org/wiki/Electron_transport_chain December 9, 2015 https://upload.wikimedia.org/wikipedia/commons/8/89/Mitochondrial_electron_transport_chain%E2%80%94Etc4.svg

8. https:// i.ytimg.com/vi/VER6xW_r1vc/maxresdefault.jpg December 9, 2015

9. Electron Carriers I (NADH-ubiquinone oxidioreductase ): An integral protein that receives electrons in the form of hydride ions from NADH and passes them on to ubiquinone II (Succinate-ubiquinone oxidioreductase aka succinate dehydrogenase from the TCA cycle): A peripheral protein that receives electrons from succinate (an intermediate metabolite of the TCA cycle) to yield fumarate and [FADH2]. From succinate the electrons are received by [FAD] (a prosthetic group of the protein) which then become [FADH2]. The electrons are then passed off to ubiquinone. Q (Ubiquinone/ ubiquinol ): Ubiquinone (the oxidized form of the molecule) receives electrons from several different carriers; from I, II, Glycerol-3-phosphate dehydrogenase, and ETF. It is now the reduced form ( ubiquinol ) which passes its electron off to III. III ( Ubiquinol -cytochrome c oxidioreductase ): An integral protein that receives electrons from ubiquinol which are then passed on to Cytochrome c IV (Cytochrome c oxidase):An integral protein that that receives electrons from Cytochrome c and transfers them to oxygen to produce water within the mitochondria matrix. ATP Synthas : An integral protein consisting of several different subunits. This protein is directly responsible for the production of ATP via chemiosmotic phosphorolation . It uses the proton gradient created by several of the other carriers in the ETC to drive a mechanical rotor. The energy from that rotor is then used to phosphorolate ADT to ATP.

10. Role of ATP in linking Catabolism and Anabolism Catabolic pathways = Metabolic pathways that release energy ( ATP) by breaking down complex molecules to simpler compounds (e.g., cellular respiration which degrades glucose to carbon dioxide and water; provides energy (ATP) for cellular work). Anabolic pathways = Metabolic pathways that consume energy ( ATP) to build complicated molecules from simpler ones (e.g., photosynthesis which synthesizes glucose from CO2 and H2O; any synthesis of a macromolecule from its monomers). Metabolic reactions may be coupled, so that energy released from a catabolic reaction can be used to drive an anabolic one. ( HERE also there is the role of ATP observed ). https:// answers.yahoo.com/question/index?qid=20080716151534AANfps8 December 9, 2015

11. Thank You