Magnesium enzyme

Younis, H.M., Weber, G. Boyer, J.S. (1983). Activity and conformational changes in chloroplast coupling factor induced by ion binding Formation of a magnesium-enzyme-phosphate complex. Biochemistry, 22, 2505-12. 

Magnesium Enzyme activator—DNA structure stabilization—Ribozymes... 

Let me sum up. A lot of magnesium enzymes are involved in energy production processes, and, many times, a phosphate-dominated molecule called ATP (adenosine triphosphate) and other cofactors are needed. Magnesium is also involved with enzymes in the metabolism of fatty acids, proteins, and carbohydrates. Magnesium is involved with heart health in the sense that it plays an important part in the interaction of... 

Further studies on this system with carbobenzoxyglycyl-L-phenylalanine (CGP) and carbobenzoxyglycyl-L-leucine (CGL) as the substrates led to the conclusion that orthophosphate, pyrophosphate, oxalate, citrate, and cyanide did not affect the initial rate of hydrolysis significantly (Neurath and de Maria, 1950). In the presence of these anions, competitive inhibition by the liberated amino acid was found to occur. These authors concluded that the anions had no effect on the enzymatic activation process and that the hypothesis that carboxypeptidase is a magnesium enzyme was devoid of experimental evidence. 

Enzymes often need for their activity the presence of a non-protein portion, which may be closely combined with the protein, in which case it is called a prosthetic group, or more loosely associated, in which case it is a coenzyme. Certain metals may be combined with the enzyme such as copper in ascorbic oxidase and selenium in glutathione peroxidase. Often the presence of other metals in solution, such as magnesium, are necessary for the action of particular enzymes. 

All organisms seem to have an absolute need for magnesium. In plants, the magnesium complex chlorophyll is the prime agent in photosynthesis. In animals, magnesium functions as an enzyme activator the enzyme which catalyses the ATP hydrolysis mentioned above is an important example. 

Mode of Action. The fluoride ion inhibits enzymes, such as enolase, which require Mg as a prosthetic group, by precipitating a complex magnesium fluorophosphate thus it prevents phosphate transfer in oxidative metaboHsm. 

HES is produced from 93—96% dextrose hydrolyzate that has been clarified, carbon-treated, ion-exchanged, and evaporated to 40—50% dry basis. Magnesium is added at a level of 0.5—5 mAf as a cofactor to maintain isomerase stabiUty and to prevent enzyme inhibition by trace amounts of residual calcium. The feed may also be deaerated or treated with sodium bisulfite at a level of 1—2-mAf SO2 to prevent oxidation of the enzyme and a resulting loss in activity. 

The Immobili dEn me System. The glucose isomerases used are immobilized and granulated to a particle size between 0.3 and 1.0 mm. The enzyme granulates must be rigid enough to withstand compaction when they are packed iato the column. Ca " acts as an inhibitor in the system, and therefore calcium salts need to be removed from the feed symp. Conversely, Mg " acts as an activator, and magnesium salts are added to the feed symp. 

In most animal, plant, and microbial cells, the enzyme that phosphorylates glucose is hexokinase. Magnesium ion (Mg ) is required for this reaction, as for the other kinase enzymes in the glycolytic pathway. The true substrate for the hexokinase reaction is MgATP. The apparent K , for glucose of the animal... 

Magnesium sulphate magnesium is an important cellular cation inorganic cofactor for many enzymatic reactions, induding those involving ATP functions in binding enzymes to substrate. 

Calcium carbonate or magnesium hydroxide antacids may decrease the effectiveness of the digestive enzymes. When administered concurrently with an iron preparation, the digestive enzymes decrease the absorption of oral iron preparations. 

Magnesium plays an important role in the transmission of nerve impulses. It is also important in the activity of many enzyme reactions, for example carbohydrate metabolism. Magnesium sulfate is used as replacement therapy in hypomagnesemia Magnesium sulfate (MgS04) is used in die prevention and control of seizures in obstetric patients with pregnancy-induced hypertension (PIH, also referred to as eclampsia and preeclampsia). It may also be added to TPN mixtures. 

CK catalyzes the reversible phosphorylation of creatine in the presence of ATP and magnesium. When creatine phosphate is the substrate, the resulting creatine can be measured as the ninhydrin fluorescent compound, as in the continuous flow Auto Analyzer method. Kinetic methods based on coupled enzymatic reactions are also popular. Tanzer and Gilvarg (40) developed a kinetic method using the two exogenous enzymes pyruvate kinase and lactate dehydrogenase to measure the CK rate by following the oxidation of NADH. In this procedure the main reaction is run in a less favorable direction. 

Figure 6, Magnesium in concentrations of 0.001-10 mM/l. produces no significant activation of alkaline phosphatase in EAE, DEA, or 2A2M1P buffers. It activates the enzyme in carbonate buffer but inhibits it in glycine buffer.

Reduced scavenger capacity is deduced from studies demonstrating low plasma and cellular levels of antioxidants such as glutathione, vitamin E, thiols, magnesium and ascorbic acid, as well as reduced levels of scavenger enzymes such as neutrophil glutathione peroxidase and red cell superoxide dismutase (Lyons, 1991 Sinclair /., 1992). 

The body s normal daily magnesium requirement is 300 to 350 mg/day to maintain a serum magnesium concentration of 1.5 to 2.4 mg/dL (0.75 to 1.2 mmol/L). Because magnesium is the second most abundant ICF cation, serum concentrations are a relatively poor measure of total body stores. Magnesium catalyzes and/or activates more than 300 enzymes, provides neuromuscular stability, and is involved in myocardial contraction. Magnesium is generally not part of standard chemistry panels, and therefore must be ordered separately.2,37,42 44,45... 

Magnesium is the second most abundant intracellular cation. Magnesium serves as an essential cofactor for numerous enzymes and in many biochemical reactions, including reactions involving adenosine triphosphate (ATP).17 Magnesium disorders can be multifactorial and can be related to renal function, disease... 

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