BIOL2056 - Williamson - Lecture 1 PDF

BIOL2056: Cell Biology: Mitochondria & Bioenergetics Dr Philip T.F. Williamson [email protected] Overview Mitochondria The anatomy and structure of a mitochondria Chemiosmotic Coupling Principle of chemiosmotic coupling Electron Transport Chain How do high energy elec...

BIOL2056: Cell Biology: Mitochondria & Bioenergetics Dr Philip T.F. Williamson [email protected] Overview Mitochondria The anatomy and structure of a mitochondria Chemiosmotic Coupling Principle of chemiosmotic coupling Electron Transport Chain How do high energy electrons get used to generate an electrochemical gradient Understand at the molecular level how the reaction complexes function to couple the transport of an electron across the bilayer to the pumping of protons ATP Generation How does the ATPase, convert and electrochemical gradient into ATP  Where do cells get their energy? Sugar Fatty Acids Amino Acids Sunlight Methane Eukaryotes Prokaryotes Mitochondria Chloroplasts Bacterial Membrane ?? Adenosine Triphosphate (ATP) Mitochondria Origins of the Mitochondria Endosymbiotic event: Double membrane cDNA Mitochondrial specific transcription/translation Human mitochondrial DNA (16 kbp), encodes: 13 respiratory chain proteins rRNA : large and small ribosomal subunits tRNA to support translation Michael W. Gray et al. Science 1999;283:1476-1481 Mitochondria derive from ancestor of Rickettsia prowazekii What are Mitochondria? Mitochondrial Matrix Reactions: TCA Cycle NADH b-oxidation of fatty acids But also: Urea cycle Amino acid synthesis Mitochondrial Protein Synthesis The TCA cycle produces biosynthetic precursors The TCA cycle provides starting materials for: Amino acids Porphyrins (haem, chlorophyll) Purines and Pyrimidines Synthesis occurs: TCA Cycle In the mitochondrial matrix e.g. porphyrins Following export of starting material to cytoplasm e.g. fatty acid biosynthesis Mitochondria Membranes Mitochondrial Membranes Membrane Composition: Phospholi OMM IMM pid PC 54 40 PE 29 34 PI 13 5 IMM is rich in proteins metabolically active PS 2 3 Both IMM and OMM are poor in CL