Adenosine triphosphatase magnesium activated

Trentham, D.R., Bardsley, R.G., Eccleston, J.F., Weeds, G. (1972). Elementary processes of the magnesium ion-dependent adenosine triphosphatase activity of heavy meromyosin. Biochem. J. 126, 635-644. 

Thompson JD, Nechay BR. 1981. Inhibition by metals of a canine renal calcium, magnesium activated adenosine triphosphatase. J Toxicol Environ Health 7 901-908. 

Lai JC, Leung TK, Lim L, et al. 1991. Effects of chronic manganese treatment on rat brain regional sodium-potassium-activated and magnesium-activated adenosine triphosphatase activities during development. Metab Brain Dis 6 165-174. 

This enzyme activity has been observed in myosin and actomyosin, mitochondria, microsomes, and cell membranes. In some cases magnesium ions function as an activator, in others calcium ions, and in still others, both calcium and magnesium are requited. Another form of adenosine-triphosphatase is stimulated by sodium and potassium ions and is inhibited by ouabain. Some forms of the enzyme can hydrolyse inosine triphosphate and other nucleoside-5 -triphosphates. The substrate specificity may depend upon the activating divalent cation and on the presence of monovalent cations. These enzymes are probably important components of a system responsible for facilitating cation transfer in membranes. They should not be confused with adenosine triphosphate pyrophosphatase E.C. 3.6.1.8. 

The magnesium-activated membrane-bound adenosine triphosphatase is important in the chemoreception of divalent ions, e.g. Ca, Mg , Zn and Co " in E. coli and S. typhimurium. The cation receptor is part of the... 

Lai, J.C.K., Guest, J.F., Leung, T.K.C., Lim, L. and Davison, A.N. (1980) The effects of cadmium, manganese and aluminum on sodium-potassium-activated and magnesium-activated adenosine triphosphatase activity and choline uptake in rat brain synaptosomes. Biochem. Pharmacol. 29, 141-146. 

A low intake of magnesium may also contribute to a higher mortality of cardiovascular disease in soft water areas. Magnesium -and also calcium - are involved in enzyme systems in the heart muscle. Sealig (1972) (54) has shown for example that inadequate magnesium concentration interferes with the activation of adenosin-triphosphatase and causes a loss of potassium by myocardial cells. This might be responsible for sudden death from coronary artery disease. 

Nelson N, Nelson H and Packer E (1972) Partial resolution of enzymes catalyzing photophosphorylation Magnesium -adenosine triphosphatase properties of heat-activated coupling factor 1 from chloroplasts, J. Biol, Chem. 247, 6506-6510. 

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