I gleaned the following from a very lengthy documentk perhaps 50 pages long. It adds the "HOW" to the picture.
Quote:
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58.What is a cytochrome? (Notes, 36) The cytochromes are electron acceptors which as a class are heme-containing proteins which mediate Fe+++/Fe++ one-electron transfers. There are five cytochromes with increasing electron accepting potentials. The heme in cytochromes b, c1, and c are Fe-protoporphyrin IX which is also the prosthetic group in myoglobin and hemoglobin. It is covalently attached to the protein in these cytochromes. 59.Which cytochrome is responsible for the reduction of molecular oxygen? (Notes, 36) Cytochrome oxidase. Contains cytochromes a and a3 as a complex, they are the terminal electron transport carriers. Each have a different prosthetic group, heme A, but th e same basic Fe-tetrapyrrole structure. It also contains two copper atoms which alternate between Cu++ and Cu+. Electron transfer through cytochrome oxidase is inhibited by cyanide or CO which appear to bind very tightly to the cytochrome a3 moiety. 60.Wha t type of structure is protoporphyrin IX? Where does it occur? (Notes, 36) The heme in cytochromes b, c1, and c are Fe-protoporphyrin IX which is also the prosthetic group in myoglobin and hemoglobin. It is covalently attached to the protein in these cytoc hromes. 61.What are several agents which inhibit electron transfer in the process of oxidative phosphorylation? (Notes, 33) It is of scientific and medical interest to note a number of chemicals which inhibit electron transport at different sites. The leth ality of cyanide and carbon monoxide depends upon the selective blockage of cytochrome oxidase. Cyanide binds to the ferric form of iron of the (a) cytochromes and carbon monoxide binds to the ferrous form. The antibiotic antimycin A blocks electron flow a t site two (cytochrome reductase), wheras rotenone and amytal block electron transfer within the NADH-Q reductase complex (below). Blockage at any site interrupts the generation of a proton gradient (below), and ATP synthesis is inhibited. Blockage sites: 62.Define the "uncoupling" of oxidative phosphorylation. What are several agents which uncouple oxidative phosphorylation? (Notes, 38) The chemiosmotic theory is supported by observations that compounds capable of disrupting a proton gradient across the in ner mitochondrial membrane effectively UNCOUPLE oxidative phosphorylation. "Uncoupling" means that electron flow and oxygen reduction proceeds without simultaneous formation of ATP. 2,4-dinitrophenol (DNP) and other phenolic compounds are effective uncoupl ers. These lipophilic compounds transfer protons across the inner mitochondrial membrane, breaking down the proton gradient. 63.How does cyanide inhibit oxidative phosphorylation? How does carbon monoxide inhibit oxidative phosphorylation? (Notes, 33) The lethality of cyanide and carbon monoxide depends upon the selective blockageof cytochrome oxidase. Cyanide binds to the ferric form of iron of the (a) cytochromes and carbon monoxide binds to the ferrous form. 64.Brifly describe the "Chemosmotic Hypotheses " of oxidative phosphorylation. (Notes, 37) The coupling of OXIDATION and PHOSPHORYLATION is indirect. Briefly stated: 1.protons are pumped from the inner to the outer side of the inner mitochondrial membrane during electron transport. 2.the inner membrane is not freely permeable to protons so an electromotive potential is established across this membrane. 3.a transmembrane multisubunit enzyme ATP synthetase (intrinsic to themitochondrial membrane) converts ADP to ATP as outermembrane protons re-enter themi tochondria through a channel coupled to ATP synthase. Supported by evidence of the pH gradient which exists across the inner mitochondrial membrane....
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I apologize for not providing the source. In my haste to report my find i forgot to save it. I have searched the web for it seveal times, but I cannot find it.
Anyway, add that to what you learned from
http://www.thesetimes.org/pointseven.html and then wonder why a cure has not been found already.