Adenosine 5 -triphosphate production

Mitochondrial heterogeneity leads to multiple simultaneous TCA cycles in astrocytes and neurons 546 Partial TCA cycles can provide energy in brain 546 Adenosine triphosphate production in brain is highly regulated 546 Phosphocreatine has a role in maintaining adenosine triphosphate levels in brain 546... 

The matrix of the phenomenological coefficients must be positive definite for example, for a two-flow system, we have Lq > 0, Ip > 0, and loTp-IopTpo > 0. Lq shows the influence of substrate availability on oxygen consumption (flow), and Lp is the feedback of the phosphate potential on ATP production (flow). The cross-coupling coefficient Lop shows the phosphate influence on oxygen flow, while Lpo shows the substrate dependency of adenosine triphosphate production. Experiments show that Onsagers s reciprocal relations hold for oxidative phosphorylation, and we have Lop = Lpo. 

Nicotinamide Adenine Dinucleotide Phosphate Adenosine Triphosphate Production Flavoprotein U = Ubiquinone... 

Figure 29.1 An overview of catabolic pathways for the degradation of food and the production of biochemical energy. The ultimate products of food catabolism are C02 and H2O, with the energy released in the citric acid cycle used to drive the endergonic synthesis of adenosine triphosphate (ATP) from adenosine diphosphate (ADP) plus phosphate ion, HOPO32-.

Thiamine can be considered to be the product of the quatemization of 4-methyl-5-(2-hydroxymethyl)thiazole (5) by an active derivative of 4-amino-5-(hydroxymethyl)-2-methyl pyrimidine (4) (Scheme 2). In living cells, pyramine can be activated by conversion into the diphosphate 7, via monophosphate 6, and the substrate of the enzyme responsible for the quatemization is not the thiamine thiazole, but its phosphate 8. The product of the condensation, thiamine phosphate (9), is finally converted into diphosphate 2—the biochemically active derivative—by hydrolysis to free thiamine, followed by diphosphorylation, or more directly, in some cases. Enzymes are known for all of the steps depicted in Scheme 2, and adenosine triphosphate (ATP) is, as usual, the phosphate donor. 

Enzymatic Assay. The enzymatic (luciferase) assay for adenosine triphosphate (ATP) is one of the methods applied to areas of biocidal control in oil production operation [1454]. A reliable method for the determination of ATP is the measurement of bioluminescence produced by the luciferin luciferase system. 

The process occurring in plants and algae by which water is oxidized to molecular oxygen and carbon dioxide is converted to carbohydrates in the presence of light is called photosynthesis. In addition to the products oxygen and carbohydrate, light energy is stored chemically in adenosine triphosphate (ATP) for later use for a variety of purposes. The production of... 

Such enzymes catalyse the condensation of specific compounds, accompanied by the breakdown of a pyrophosphate bond in adenosine triphosphate (10.64). Adenosine is the condensation product of a pentose (D-ribofuranose) and a purine (adenine). Scheme 10.15 shows the action of glutamine synthetase on a mixture of L-glutamic acid (10.65) and... 

Andre et al. [8] discuss the determination of adenosine-5 -triphosphate by luciferin-luciferase assay. This method was applied to the determination of adenosine-5 -triphosphate in bacterial colonies filtered from samples of polluted water after incubation for different periods. The adenosine-5 -triphosphate was extracted from the residue in the filter and the amount compared with the biochemical oxygen demand of the filtered water. The oxygen uptake rate and the rate of formation of adenosine-5 -triphosphate were then plotted against time, the two curves being similar in up to three to four days incubation, after which adenosine-5 -triphosphate production declined markedly, although oxygen uptake continued to increase. 

The energy released is used to transfer protons across the photosynthetic membrane and ultimately this energy acts as a driving force for the catalysed production of high-energy adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and inorganic phosphate. 

In some cases, enzymes require the assistance of coenzymes (cofactors) to ensure the reactions proceed. Coenzymes include vitamins, metal ions, acids, and bases. They can act as transporters or electron acceptors or be involved in oxidation-reduction reactions. At the completion of the reaction, coenzymes are released, and they do not form part of the products. For some reactions that are energetically unfavorable, an energy source provided by the compound adenosine triphosphate (ATP) is needed to ensure the reactions proceed, as shown in the following reactions ... 

Mitochondria are found in the cell body and all processes of the neuron. They possess a double membrane and their own DNA and they play a role in cellular respiration and energy synthesis. Mitochondria contain enzymes essential for energy production in the form of adenosine triphosphate (ATP). 

Note that equation 5.2 is irreversible and the product AMP will require two phosphorylation steps to reconstitute the high-energy adenosine triphosphate, ATP. Inositol 1,4,5-triphosphate is an important molecule in the cytosol, where it releases calcium ions from storage. It forms part of a series of inositol-phosphate species that mediate calcium ion concentrations inside and outside the cell. 

Adenosine triphosphate is utilized in portions of the cell other than the mitochondria and chloroplasts therefore, the utilization as well as the production of ATP is of importance to total adenylate status. As a result, it became important to consider total ATP content of plants. When detached pinto bean leaves were exposed to 1,0 yl/1 ozone for 30 min total ATP content of the leaf decreased (12), Since ozone altered leaf ATP content it could also alter the leaf s adenylate status we wished to determine if a correlation existed between alteration in adenylates and the change previously reported in photosynthesis and respiration. Since ATP is readily broken down by adenosine triphosphatases, a reliable method of extraction and quantitative method of ATP analysis was designed for the study (8),... 

Since active transport often requires energy in the form of adenosine triphosphate (ATP), compounds or conditions that inhibit energy production (e.g., iodoac-etate, fluoride, cyanide, anaerobiosis) will impair active transport. The transport of a given compound also can be inhibited competitively by the coadministration of other compounds of sufficient structural similarity that they can compete with the first substance for sites on the carrier protein. 

Adenosine (Adenocard) is an endogenous nucleoside that is a product of the metabolism of adenosine triphosphate. It is used for the rapid termination of supraventricular arrhythmias following rapid bolus dosing. 

The second messenger, cyclic adenosine monophosphate (cAMP), is thought to mediate the bronchodila-tor effects of the adrenomimetics. Adrenomimetics enhance the production of cAMP by activating adenylyl cyclase, the enzyme that converts adenosine triphosphate (ATP) to cAMP. This process is triggered by the interaction of the adrenomimetics with 2-(tdrenoceptors on airway smooth muscle. 

Subcellular membrane-bound enzymes activity. Oil, administered to male CFY weanling rats at a dose of 20% for 16 weeks, produced an increase of synaptosomal acetylcholinesterase activity in the coconut oil-fed group. The Mg -adenosine triphosphate (ATPase) activity was similar among all groups in all the brain regions Superoxide production inhibition. Seed oil, administered to rats at a concentration of 8% of diet, produced equivocal effect on macrophages. Capsaicin or curcumin enhanced effect . ... 

Mechanism of Action Aproton pump inhibitor that is converted to active metabolites that irreversibly bind to and inhibit hydrogen-potassium adenosine triphosphates, an enzyme on the surface of gastricparietal cells. Inhibits hydrogen ion transport into gastric lumen. Therapeutic Effect Increases gastricpH, reducing gastric acid production. 

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