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(1989) A perspective of the bindingchange mechanism for ATP synthesis. FASEB J.3, 2164-2178.An article on the historical development and current state of the binding-change model, by its principal architect.Futai, M., Noumi, T., & Maeda, M. (1987) Molecular biological studies on structure and mechanismof proton translocating ATPase (H+-ATPase, FoFi).Adv. Biophys. 23, 1-37.Insight into the mechanism of ATP synthase fromstudies of the genes that encode its subunits.Pedersen, P.L. & Carafoli, E. (1987) Ion motiveATPases. I. Ubiquity, properties, and significanceto cell function. Trends Biochem. Sci. 12,145-150.II. Energy coupling and work output. Trends Biochem. Sci.
12, 186-189.Two short reviews that place ATP synthase withinthe family of ATP-dependent proton pumps; include their general mechanisms.Douce, R. & Neuburger, M. (1989) The uniqueness of plant mitochondria. Annu. Rev. Plant Physiol. Plant MoL Biol. 40, 371-414.A focus on the features of plant mitochondria thatdistinguish them from mitochondria of animalcells.Penefsky, H.S. & Cross, R.L. (1991) Structureand mechanism of F0Fi-type ATP synthases andATPases.
Adv. Enzymol. Relat. Areas Mol. Bio. 64,173-214.An advanced discussion.Hinkle, P.C. & McCarty, R.E. (1978) How cellsmake ATP. Sci. Am. 238 (March), 104-123.Although not recent, this is an excellent, readable,and well-illustrated description of oxidative phosphorylation.Ricquier, D., Casteilla, L., & Bouillaud, F. (1991)Molecular studies of the uncoupling protein.FASEB J. 5, 2237-2242.A discussion of the protein and its role in thermogenesis.Lehninger, A.L., Reynafarje, B., Alexandre, A.,& Villalobo, A. (1980) Respiration-coupled H +ejection by mitochondria.
Ann. N. Y. Acad. Sci. 341,585-592.The methods and problems in measuring protonefflux stoichiometry.Senior, A.E. (1988) ATP synthesis by oxidativephosphorylation. Physiol. Rev. 68, 177-231.An advanced but very clear review, with an emphasis on the mechanism of ATP synthase.Malmstrom, B.G. (1989) The mechanism of protontranslocation in respiration and photosynthesis.FEBS Lett. 250, 9-21.Comparative review of the electron-transferringcomplexes of mitochondria and chloroplasts.Brand, M.D. & Murphy, M.P. (1987) Control ofelectron flux through the respiratory chain in mitochondria and cells.
Biol. Rev. Cambridge Phil. Soc.62, 141-193.An advanced description of respiratory control.Trumpower, B.L. (1990) The protonmotive Q cycle:energy transduction by coupling of proton translocation to electron transfer by the cytochrome beicomplex. J. Biol. Chem. 265, 11409-11412.Short, clear description of the Q cycle and electronflow through Complex III.Harris, D.A. & Das, A.M. (1991) Control of mitochondrial ATP synthesis in the heart. Biochem.
J.280, 561-573.An advanced discussion of regulation of the ATPsynthase by Ca2+ and other factors.Regulation of MitochondrialPhosphorylationOxidative594Part III Bioenergetics and MetabolismPhotosynthesis: Harvesting Light EnergyGreen, B.R., Pichersky, E., & Kloppstech, K.(1991) Chlorophyll a/6-binding proteins: an extended family. Trends Biochem. Sci. 16, 181-186.An intermediate-level description of the proteinsthat orient chlorophyll molecules in chloroplasts.Huber, R. (1990) A structural basis of light energyand electron transfer in biology.
Eur. J. Biochem.187, 283-305.The author's Nobel lecture, describing the physicsand chemistry ofphototransductions. An exceptionally clear and well-illustrated discussion, based oncrystallographic studies of reaction centers.Zuber, H. (1986) Structure of light-harvesting antenna complexes of photosynthetic bacteria, cyanobacteria and red algae.
Trends Biochem. Sci. 11,414-419.Light-Driven Electron FlowAndreasson, L.-E. & Vanngard, T. (1988) Electrontransport in photosystems I and II. Annu. Rev.Plant Physiol. Plant Mol. Biol. 39, 379-411.An advanced description of the path of electron flowin chloroplasts, studied with spectroscopic techniques.Blankenship, R.E. & Prince, R.C. (1985) Excitedstate redox potentials and the Z scheme of photosynthesis. Trends Biochem. Sci. 10, 382-383.A concise and lucid statement of the redox properties of excited states.Deisenhofer, J.
& Michel, H. (1991) Structures ofbacterial photosynthetic reaction centers. Annu.Rev. Cell Biol. 7, 1-23.The structure of the reaction center of purple bacteria, and implications for the function of bacterialand plant reaction centers.reaction centers: structure, organization, and function. Annu. Rev. Plant Physiol. 38, 11-45.An advanced description of the structure and function of reaction centers of green plants, cyanobacteria, and purple and green bacteria.Golbeck, J.H.
(1992) Structure and function ofphotosystem I. Annu. Rev. Plant Physiol. PlantMol. Biol. 43, 293-324.Govindjee & Coleman, W.J. (1990) How plantsmake oxygen. Sci. Am. 262 (February), 50-58.An exceptionally clear account of the water-splitting activity of photosystem II.Nitschke, W. & Rutherford, A.W. (1991) Photosynthetic reaction centres: variations on a commonstructural theme? Trends Biochem. Sci.
16, 241245.A comparison of the structure and function of photosystems I and II and the reaction centers of several photosynthetic bacteria.Coupling ATP Synthesis to Light-DrivenElectron FlowCramer, W.A., Widger, W.R., Herrmann, R.G., &Trebst, A. (1985) Topography and function of thylakoid membrane proteins. Trends Biochem. Sci.10, 125-129.Jagendorf, A.T. (1967) Acid-base transitions andphosphorylation by chloroplasts. Fed. Proc. 26,1361-1369.The classic experiment establishing the ability of aproton gradient to drive ATP synthesis in the dark.Youvan, D.C. & Marrs, B.L.
(1987) Molecularmechanisms of photosynthesis. Sci. Am. 256(June), 42-48.An excellent description of the chemical basis forlight reactions.Glazer, A.N. & Melis, A. (1987) PhotochemicalProblems1. Oxidation-Reduction Reactions The NADHdehydrogenase complex of the mitochondrial respiratory chain promotes the following series of oxidation-reduction reactions, in which Fe 3+ and Fe 2+represent the iron in iron-sulfur centers, UQ isubiquinone, UQH2 is ubiquinol, and E is the enzyme:(1) NADH + H- + E-FMN -> NAD+ + E-FMNH2(2) E-FMNH2 + 2Fe3+ -> E-FMN + 2Fe2+ + 2H~(3) 2Fe2+ + 2H+ + UQ -> 2Fe3+ + UQH2Sum: NADH + H + UQ -> NAD+ + UQH2For each of the three reactions catalyzed by theNADH dehydrogenase complex, identify (a) theChapter 18 Oxidative Phosphorylation and Photophosphorylationelectron donor, (b) the electron acceptor, (c) theconjugate redox pair, (d) the reducing agent, and(e) the oxidizing agent.2.
Standard Reduction Potentials The standardreduction potential of any redox couple is definedfor the half-cell reaction (or half-reaction):Oxidizing agent + n electrons>reducing agentThe standard reduction potentials of the NAD+/NADH and pyruvate/lactate redox pairs are-0.320 and -0.185 V, respectively.(a) Which redox pair has the greater tendencyto lose electrons? Explain.(b) Which is the stronger oxidizing agent? Explain.(c) Beginning with 1 M concentrations of eachreactant and product at pH 7, in which directionwill the following reaction proceed?Pyruvate + NADH + H+lactate + NAD+(d) What is the standard free-energy change,AG°', at 25 °C for this reaction?(e) What is the equilibrium constant for thisreaction at 25 °C?3.
Energy Span of the Respiratory Chain Electrontransfer in the mitochondrial respiratory chainmay be represented by the net reaction equationNADH + H+iO2H2O + NAD+(a) Calculate the value of the change in standard reduction potential, AEb, for the net reactionof mitochondrial electron transfer.(b) Calculate the standard free-energy change,AG°', for this reaction.(c) How many ATP molecules could theoreticallybe generated per molecule of NADH oxidized bythis reaction, given a standard free energy of ATPsynthesis of 30.5 kJ/mol?(d) How many ATP molecules could be synthesized under typical cellular conditions (see Box13-2)?4. Use of FAD Rather Than NAD+ in the Oxidationof Succinate All the dehydrogenation steps in glycolysis and the citric acid cycle use NAD+ {E'Q forNAD+/NADH = -0.32 V) as the electron acceptorexcept succinate dehydrogenase, which uses covalently bound FAD (Ed for FAD/FADH2 in this enzyme = 0.05 V).
Why is FAD a more appropriateelectron acceptor than NAD+ in the dehydrogenation of succinate? Give a possible explanationbased on a comparison of the Ed values of the fumarate/succinate pair (Ed = 0.03), the NAD+/NADHpair, and the succinate dehydrogenase FAD/FADH2 pair.5. Degree of Reduction of Electron Carriers in theRespiratory Chain The degree of reduction of eachelectron carrier in the respiratory chain is determined by the conditions existing in the mitochondrion. For example, when the supply of NADH and595O2 is abundant, the steady-state degree of reduction of the carriers decreases as electrons passfrom the substrate to O2. When electron transfer isblocked, the carriers before the block become morereduced while those beyond the block become moreoxidized (Fig. 18-7).
For each of the conditionsbelow, predict the state of oxidation of each carrierin the respiratory chain (ubiquinone and cytochromes b, Ci, c, and a + a3).(a) Abundant supply of NADH and O2 but cyanide added(b) Abundant supply of NADH but O2 exhausted(c) Abundant supply of O2 but NADH exhausted(d) Abundant supply of NADH and O26.
The Effect ofRotenone and Antimycin A on Electron Transfer Rotenone, a toxic natural productfrom plants, strongly inhibits NADH dehydrogenase of insect and fish mitochondria. Antimycin A, atoxic antibiotic, strongly inhibits the oxidation ofubiquinol.(a) Explain why rotenone ingestion is lethal tosome insect and fish species.(b) Explain why antimycin A is a poison.(c) Assuming that rotenone and antimycin Aare equally effective in blocking their respectivesites in the electron transfer chain, which would bea more potent poison? Explain.7. Uncouplers of Oxidative Phosphorylation Innormal mitochondria the rate of electron transferis tightly coupled to the demand for ATP.
Thuswhen the rate of utilization of ATP is relativelylow, the rate of electron transfer is also low. Conversely, when ATP is demanded at a high rate,electron transfer is rapid. Under such conditions oftight coupling, the number of ATP molecules produced per atom of oxygen consumed when NADHis the electron donor—known as the P/O ratio—isclose to 3.(a) Predict the effect of a relatively low and arelatively high concentration of an uncouplingagent on the rate of electron transfer and the P/Oratio.(b) The ingestion of uncouplers causes profusesweating and an increase in body temperature.Explain this phenomenon in molecular terms.What happens to the P/O ratio in the presence ofuncouplers?(c) The uncoupler 2,4-dinitrophenol was onceprescribed as a weight-reducing drug.
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