The coupled mechanism of oxidizing phosphate.

. NameThe co-online theology of oxidation
phosphate
has been studied many times, the current co-online theology of oxidation phosphate is not completely clear, slater and Lehninger put forward the the theorization of chemical association in the 1950s, and in 1964 Boear put forward the the theor of the association of structural changes, the experimental basis of these two theorists is not much, the people who support these two views are not many. Most people now support the the thesis of chemical permeation, which was put forward by P. Mitchell, a British
biochemical
scientist, in 1961, when it was not taken seriously, and which he gradually perfected in 1966 on the basis of accumulated experimental evidence and advances in biofilm research.The basic point of view ofchemical permeation theory of oxidizing phosphorylation is: 1. The electron transmission in the endometrium of the mitochondrial is coupled with the release of H-plus by the mitochondrial, i.e. the energy released by the respiratory chain in the transmission of electrons continuously pumps the H-plus inverse concentration gradient out of the membrane in the mitochondrial substate, and the molecular structure of this process is not very clear (see Figure 6-14).6-14 Electron transfer and proton transfer coupled (Note: Complex II. not shown) 2.H-plus can not freely pass through the mitochondrial membrane, resulting in a higher concentration of the outer side of the membrane in the mitochondrial body H-plus concentration The concentration of H-plus in the substitut is reduced, a proton cross-membrane gradient is formed on both sides of the membrane in the mitochondrial body, the outer side of the membrane in the mitochondrial is positively charged, and the inner membrane is negatively charged, which is the transfilm potential ψ. Due to the different concentrations of H-plus on both sides of the membrane in mitochondrials, there is also a pH gradient pH on both sides of the inner membrane, pH on the outside of the membrane is about 1.0 units lower than the substrate pH, the free ψ energy released during the substrate oxidation process is stored in the pH, if the total proton movement force is represented by p, then the relationship between the three can be expressed in the following way:P ψ. -59 pH . Outside the mitochondrial body, H-plus can enter the mitochondrial substitut by following the three molecules on the membrane of the mitochondrial body along the H-concentration gradient, which is equivalent to a specific proton channel, the free energy released by the movement of the H-plus gradient direction is used for ATP synthesis, oligonomics can bind to OSCP, specifically blocking this H-channel, thereby inhibiting ATP synthesis. The molecular mechanism of ATP synthesis is not yet clear.. 4. The role of the anti-coupled agent is to promote the passive diffusion of H-plus through the mitochondrial membrane, that is, to enhance the permeability of the mitochondrial membrane to H-plus, the anti-coupled agent can eliminate the proton gradient on both sides of the membrane in the mitochondrial body, so it can no longer be synthesized ATP., the thesis of chemical permeability holds that the factor that couples oxidation with phosphate is the cross-membrane gradient of H-plus.each pair of H-plus can be returned to the mitochondrial substation via a tri-molecular body to produce a molecule ATP. As a substrate, the electrons are transmitted along the respiratory chain to form three circuits in the membrane of the online granules, so 3 molecules ATP are generated. With FADH2 as the substrate, its electrons are transmitted along the amber acid oxidation respiratory chain to form two circuits in the membrane of the in vivo of the mitochondrial, so two ATP molecules are generated.since Mitchell proposed the thesis of chemical permeable, it has verified a large number of experimental results and provided an experimental basis for this thesis.the United States, Cohen et al. used the complete
rat
liver cells as experimental materials in 1978 for nuclear magnetic resonance,
NMR
) method directly observed that there is an H-plus trans-membrane gradient between the cytostomal fluid and the mitochondrial substitum in the complete cell, the pH of the cell fluid is 0.3 units lower than the pH of the mitochondrial substitum, treated with an anti-coupled agent, or nitrogen instead of oxygen to cut off the supply of oxygen, then the pH gradient between the cell fluid and the mitochondrial substitial disappears.the halobacterium haloblum, a bacteria that grows in high-concentration salt solutions, has a combination of
protein
, called bacteriorhodopsin, which converts light energy into chemical energy. Some people use salt-phile bacteria for experiments, in the absence of O2 with light exposure to salt-like bacteria, although no oxidation effect, the bacteria still maintain a certain concentration of ATP in the body, if added to the anti-coupled agent or added phosphorylation inhibitor DCC, then the concentration of ATP in the bacteria The addition of respiratory inhibitors inhibits electron transfer, i.e. does not affect ATP synthesis, and the ATP concentration remains unchanged, indicating that electron transmission and H-plus motion can be studied separately, and salt-free bacteria provide an ideal model for the study of the theory of chemical permeability of H-plus motion. Thus, someone isolates the bacteria purple of the salt-eating bacteria, and recombines it in the artificial lipid body, and then irradiates with light, the cross-membrane potential can be measured to 120mV (inner negative external positive), while the concentration of the outer side of the membrane increases, the inside and outside of the membrane pH is about 1.8 units, can calculate the total proton movement force is about P-120m V-59×1.8mV- 226mV, if the bovine heart mitochondrial membrane recombination in this lipid body, lighting can make ADP-Pi generate ATP, which indicates that proton transfilm gradient can pass through the mitochondrial membrane of the three molecules of the H-plus trans-membrane gradient to convert the energy stored in the ATP molecule into chemical energy in the ATP molecule.
.
.