Chapter 6 Energy Generation in Mitochondria and Chloroplasts (1)Mitochondria: in all eukaryotic cells The relationship between the structure and function of mit. (2)Chloroplasts: in plant cells The relationship between the structure and function of chl. Mit: Oxidative phosphorylation- ATP Chl: Photosynthesis→ATP+ NADPH→ Sugar
Energy Generation in Mitochondria and Chloroplasts Chapter 6 (1) Mitochondria: in all eukaryotic cells The relationship between the structure and function of mit. (2) Chloroplasts: in plant cells The relationship between the structure and function of chl. Mit: Oxidative phosphorylation→ ATP Chl: Photosynthesis→ ATP+NADPH→ Sugar
Photosynthesis Aerobic respiration Chloroplast CHOH Mitochondrion C2+H20 CO2+ H2O Carbohydrate ATP(contains high energy electrons NADH ADP NADP+ NAD+ chemical energy (ATP) Light energy H20 (contains low energy electrons Figure 6.4 An overview of the energetics of photosynthesis and aerobic respiration
Mitochondria and oxidative phosphorylation A. Mitochondrial structure and function The size and number of mitochondria reflect the energy requirements of the cell. mitochondria contractile ③0 CARDIAC MUSCLE CELL SPERM TAIL
A. Mitochondrial structure and function vThe size and number of mitochondria reflect the energy requirements of the cell. 1. Mitochondria and oxidative phosphorylation
nner and outer mitochondrial membranes enclose two spaces: the matrix and intermembrane space
vInner and outer mitochondrial membranes enclose two spaces: the matrix and intermembrane space
Outer membrane. Contains channel-forming protein, called porin Permeable to all molecules of 5000 daltons or less Inner membrane(Impermeability) Contains proteins with three types of functions (1)Electron-transport chain: Carry out oxidation reactions 2)ATP synthase: Makes ATP in the matrix; (3) Transport proteins: Allow the passage of metabolites Intermembrane space: Contains several enzymes use ATP to phosphorylate other nucleotides Matrix: Enzymes; Mit DNA, Ribosomes, etc
Outer membrane: Contains channel-forming protein, called Porin. Permeable to all molecules of 5000 daltons or less. Inner membrane (Impermeability): Contains proteins with three types of functions: (1) Electron-transport chain: Carry out oxidation reactions; (2) ATP synthase: Makes ATP in the matrix; (3) Transport proteins: Allow the passage of metabolites Intermembrane space: Contains several enzymes use ATP to phosphorylate other nucleotides. Matrix: Enzymes; Mit DNA, Ribosomes, etc
B Specific functions localized within the Mit by disruption of the organelle and fractionation INTACT matrix transfer to a medium of high MITOCHONDRION outer membrane osmolarity causes shrinkage inner membrane ntermem brane in medium of low osmolarity the influx of water causes the mitochondrion to swell and the outer membrane to rupture, releasing density-gradient centrifugation the contents of the intermembrane separates the outer membrane space; the inner membrane remains from the dense matrix and its intact surrounding membrane disruption and centrifugation separate inner membrane from matrix components centrifugation leaves the contents of the intermembrane space in the nonsedimenting fraction INNER MATRIX OUTER MEMBRANE MEMBRANE INTERMEMBRANE
B. Specific functions localized within the Mit by disruption of the organelle and fractionation
Localization of meta bolic functions within the mitochondrion Outer membrane. Inner membranes Phospholipid synthesis Electron transport fatty acid desaturation Oxidative phosphorylation Fatty acid elongation Metabolite transport Mark: monoamine oxidase Cardiolipin/TPL(20%) Matrix Mark: cytochrome oxidase Pyruvate oxidation Intermembrane space TCA cycle Nucleotide phosphorylation B oxidation of fats Mark: adenylate kinase DNA replication, RNa transcription Protein translation Mark: MDh
Localization of metabolic functions within the mitochondrion Outer membrane: Phospholipid synthesis fatty acid desaturation Fatty acid elongation Mark:monoamine oxidase Inner membrane: Electron transport Oxidative phosphorylation Metabolite transport Cardiolipin/TPL(20%) Mark:cytochrome oxidase Intermembrane space Nucleotide phosphorylation Mark: adenylate kinase Matrix Pyruvate oxidation TCA cycle ß oxidation of fats DNA replication, RNA transcription, Protein translation Mark: MDH
2. Molecular basis of oxidative phosphorylation outer mitochondrial membrane inner mitochondrial membrane 2H20 ATP OUT ATP NAD NADH O ADP ADP+Pi citrIc OUL.CO acetyl CoA
2. Molecular basis of oxidative phosphorylation
A. Molecular basis of oxidation: Electron transport chain Intermembrane space ⅣaC e-S Matrⅸx 2H+ Succinate NADH 1/202+2H Complex I Complex Ill Complex ll ComplexⅣ NADH Cytochrome bcl Succinate Cytochrome c enyarogenase dehydrogenase Oxidase SUBUNITS Mammalian mtDNA 3 nDNA 10 13
A. Molecular basis of oxidation: Electrontransport chain
B. Molecular basis of phosphorylation: ATP synthase The structure of the atP synthase FI particle is the catalytic subunit; The Fo particle attaches to Fi and is embedded in the inner membrane F: 5 subunits in s the ratio 3∞:3:ly:18:l F.1a:2b:12c aO Matrix 0.01m a Intermembrane space UU
B. Molecular basis of phosphorylation: ATP synthase v The structure of the ATP synthase F1 particle is the catalytic subunit; The F0 particle attaches to F1 and is embedded in the inner membrane. F1: 5 subunits in the ratio 3:3:1:1:1 F0: 1a：2b：12c