Adenosine triphosphate , biological

A naturally occurring sulfonium salt S adenosylmethionme (SAM) is a key sub stance in certain biological processes It is formed by a nucleophilic substitution m which the sulfur atom of methionine attacks the primary carbon of adenosine triphosphate dis placing the triphosphate leaving group as shown m Figure 16 7... 

Adenosine triphosphate (ATP) is a key compound m biological energy storage and delivery... 

R. W., and Veech, R. L., 1973. The cqnitibrimn constants of the adenosine triphosphate hydrolysis and the aelenosine triphos-phate-eitrate lyase rc<7cfions. Journal of Biological Chemisti y 2A%i6966- 6972.)... 

The most common example of this process in living organisms is the reaction of the amino acid methionine with adenosine triphosphate (ATP Section 5.8) to give S-adenosylmethionine. The reaction is somewhat unusual in that the biological leaving group in this SN2 process is the triphosphate ion rather than the more frequently seen rliphosphate ion (Section 11.6). 

Today, bioluminescence reactions are used as indispensable analytical tools in various fields of science and technology. For example, the firefly bioluminescence system is universally used as a method of measuring ATP (adenosine triphosphate), a vital substance in living cells Ca2+-sensitive photoproteins, such as aequorin from a jellyfish, are widely utilized in monitoring the intracellular Ca2+ that regulates various important biological processes and certain analogues... 

Aguilar-Bryan L, Bryan J (1999) Molecular biology of adenosine triphosphate-sensitive potassium channels. Endocr Rev 20 101-135... 

Adenosine triphosphate (ATP) is an extremely important molecule in biological systems. Consult standard reference sources in your library to describe how this molecule is used in energy transfer to facilitate nonspontaneous processes necessary for life. 

Phosphate also plays a central role in the transmission and control of chemical energy within the cells primarily via the hydrolysis of the terminal phosphate ester bond of the adenosine triphosphate (ATP) molecule (Fig. 14-3b). In addition, phosphate is a necessary constituent of phospholipids, which are important components in cell membranes, and as mentioned before, of apatite, which forms structural body parts such as teeth and bones. It is not surprising, therefore, that the cycling of P is closely linked with biological processes. This connection is, in fact, inseparable as organisms cannot exist without P, and their existence controls, to a large extent, the natural distribution of P. 

Vinyl alcohol copolymer gel is hydrophilic and has been developed for aqueous-phase size-exclusion liquid chromatography however, it is less polar than the polysaccharides. Its specificity permits the direct injection of a biological sample without deproteinization. For example, blood serum from a patient suffering from chronic nephritis has been injected directly as a measure of the degree of dialysis (Figure 3.17). Adenosine triphosphate, adenosine diphosphate, and adenosine monophosphate in red blood cells have also been separated directly (Figure 3.18). Theophylline in blood serum has been... 

F -ATPase Driven Nanomotors. Another type of biological driven engine is that of Fi-adenosine triphosphate synthease (Fi-ATPase) which hydrolyzes the ATP in the surrounding medium. Kinosita Jr. et al. observed the rotation of an actin filament attached to the Fi - ATPase motor. Later, Montemagno followed with the incorporation of a nickel nanorod with the Fi-ATPase motor. The outcome was the rotation of the... 

Similarly, specific catalysts called enzymes are important factors in determining what reactions occur at an appreciable rate in biological systems. For example, adenosine triphosphate is thermodynamically unstable in aqueous solution with respect to hydrolysis to adenosine diphosphate and inorganic phosphate. Yet this reaction proceeds very slowly in the absence of the specific enzyme adenosine triphosphatase. This combination of thermodynamic control of direction and enzyme control of rate makes possible the finely balanced system that is a hving cell. 

The hydrolysis of adenosine triphosphate (ATP), an exergonic reaction [Equation (7.89)], is frequently used in biologic systems to drive endergonic reactions. The value of AGmfor this reaction is —29,3001 mol ... 

Phosphate ion is a major participant in the biological energy cycle through the reactions of mono-, di-, and triphosphates, including one of the most important of these reactions, producing adenosine diphosphate from adenosine triphosphate (see structures in Section 2.3.1, Table 2.2) ... 

Phosphorus is one of the inorganic macronutrients in all known forms of life. Inorganic phosphorus in the form of phosphate (PO/ ) plays a major role in vital biological molecules, such as DNA and RNA. Living cells also utilize phosphate to transport cellular energy via adenosine triphosphate (ATP). Phospholipids are the main structural components of all cellular membranes. Calcium phosphate salts are... 

Magnesium ions are also involved in biological processes and occur in cells at millimolar concentrations [315]. Magnesium can be estimated based on the chemical shift difference of the resonances of adenosine triphosphate (ATP) using P NMR [316-318], though P NMR has intrinsically low signal-to-noise, exacerbated under many pathophysiological conditions, such as ischemia. 

Biological chemistry takes place in the aqueous environment of the body of an animal or plant. Therefore, in spite of the fact that the molecules involved are largely organic in nature, the chemistry is essential acid-base chemistry and therefore a good candidate for the application of the bond valence model, as the example of adenosine triphosphate discussed in the previous section (Section 13.5.4) shows. This section illustrates a number of other ways in which the model has been used in biological systems. 

Monosaccharides also form phosphate esters with phosphoric acid. Monosaccharide phosphate esters are important molecules in biological system. For example, in the DNA and RNA nucleotides, phosphate esters of 2-deoxyribose and ribose are present, respectively. Adenosine triphosphate (ATP), the triphosphate ester at C-5 of ribose in adenosine, is found extensively in living systems. 

An important tetradentate ligand is adenosine triphosphate (ATP), which binds to divalent metal ions (such as Mg2+, Mn2+, Co24, and Ni2+) through four of their six coordination positions (Figure 12-2). The fifth and sixth positions are occupied by water molecules. The biologically active form of ATP is generally the Mg2+ complex. 

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