Adenosine triphosphate reactions

FIGURE 16 7 Nucleophilic substitution at the primary carbon of adenosine triphosphate (ATP) by the sulfur atom of methionine yields S adenosylmethionme (SAM) The reaction is catalyzed by an enzyme... 

Adenosine triphosphate (ATP) Common energy-donating molecule in biochemical reactions. Also an important compound in transfer of phosphate groups. 

Ill these simultaneous reactions, die energy released when the complex molecule AB is broken down is immediately used to build a molecule of adenosine triphosphate (ATP) from a molecule of adenosine diphosphate (ADP) and an inorganic phosphate (P,). ATP is a high energy compound. It is called the energy currency of the body because once it is formed, it provides energy that the body can spend later to drive vital reactions in cells (Figure 1). 

Sometimes, particularly in biochemistry, reactive substances that undergo highly exothermic reactions, such as ATP adenosine triphosphate), are referred... 

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). 

In fatty-acid biosynthesis, a carboxylic acid is activated by reaction with ATP to give an acyl adenylate, which undergoes nucleophilic acyi substitution with the — SH group or coenzyme A. (ATP = adenosine triphosphate AMP = adenosine monophosphate.)... 

The energy released in catabolic pathways is used in the electron-transport chain to make molecules of adenosine triphosphate, ATP. ATP, the final result of food catabolism, couples to and drives many otherwise unfavorable reactions. 

Adenosine triphosphate, coupled reactions and. 1128-1129 function of, 157, 1127-1128 reaction with glucose, 1129 structure of, 157, 1044 S-Adenosylmethionine, from methionine, 669 function of, 382-383 stereochemistry of, 315 structure of, 1045 Adipic acid, structure of, 753 ADP, sec Adenosine diphosphate Adrenaline, biosynthesis of, 382-383 molecular model of, 323 slructure of, 24... 

ADP (adenosine diphosphate) and ATP (adenosine triphosphate) are complex organic molecules (Fig. 17.9) that, in essence, differ only hy the presence of an extra phosphate group in ATP. In the coupled reaction with glucose, about 38 mol of ATP are synthesized for every mole of glucose consumed. This gives an overall free energy change for the coupled reaction of... 

McElroy, W. D., and Strehler, B. L. (1949). Factors influencing the response of the bioluminescent reaction to adenosine triphosphate. Arch. Biochem. 22 420-433. 

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... 

The relative strengths of bonds are important for understanding the way that energy is used in bodies to power our brains and muscles. For instance, adenosine triphosphate, ATP (35), is found in ever)- living cell. The triphosphate part of this molecule is a chain of three phosphate groups. One of the phosphate groups is removed in a reaction with water. The P O bond in ATP requires only 276 kjmol-1 to break and the new P—O bond formed in H2P04 releases 350 kj-mol-1 when it forms. As a result, the conversion of ATP to adenosine diphosphate, ADP, in the reaction... 

C13-0024. Nucleotides can contain more than one phosphate group. One example is energy-storing adenosine triphosphate (ATP), which is discussed in Chapter 14. An ATP molecule is formed in two sequential condensation reactions between phosphoric acid and the phosphate group of AMP ... 

Phosphate condensation reactions play an essential role in metabolism. Recall from Section 14.6 that the conversion of adenosine diphosphate (ADP) to adenosine triphosphate (ATP) requires an input of free energy ADP -I-H3 PO4 ATP +H2O AG° — +30.6kJ As also described in that section, ATP serves as a major biochemical energy source, releasing energy in the reverse, hydrolysis, reaction. The ease of interchanging O—H and O—P bonds probably accounts for the fact that nature chose a phosphate condensation/hydrolysis reaction for energy storage and transport. 

A remarkable feature of the bioenergetic oxidation reactions of nutrients in cells is the fact that they are always coupled to another reaction, that of synthesis of the energy-rich chemical substance adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and phosphate (oxidative phosphorylation Engelgardt and Ljubimova, 1939) ... 

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... 

In the processes that require regeneration of cofactors such as nicotinamide adenine dinucleotide phosphate (NAD(P)H) and adenosine triphosphate (ATP), whole-cell biotransformations are more advantageous than enzymatic systems [12,15]. Whole cells also have a competitive edge over the isolated enzymes in complex conversions involving multiple enzymatic reactions [14]. 

Figure 1. The separation of the half reaction in the chloroplast of the photosynthetic plant cell. The dark reaction (left) and the light-driven reactions (right) are shown. Key NADP oxidized form of nicotinamide adenine dinucleotide phosphate ATPf adenosine triphosphate and Pit inorganic phosphate.

Although already in 1947 McElroy discovered that adenosine triphosphate (ATP) and magnesium were essential for the BL reactions by which fireflies produce... 

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