Adenosine triphosphate, coupled reactions hydrolysis

The positive standard free energy implies nonspontaneity for reaction (1). To generate glucose-6-phosphate, reaction (1) is coupled with (2), the hydrolysis of adenosine triphosphate (ATP) to yield adenosine diphosphate (ADP). Reaction (2) has a favorable AG,° < 0 value spontaneous)-. 

In all eukaryotic cells, the eflEcient use of carbohydrate, fat or protein as an energy source depends on the complete oxidation of constituent carbon atoms to carbon dioxide. The energy available from these oxidations is conserved through the coupled synthesis of adenosine triphosphate (ATP) from adenosine diphosphate (ADP) and phosphate (Pi) and used to drive the kinetic, biosynthetic and homeostatic processes of the cell through numerous concerted reactions involving the hydrolysis of ATP back to ADP. 

However, the hydrolysis of adenosine triphosphate can pump the ions only if some degrees of coupling exist between the reaction velocity and the mass flow. The efficiency of energy conversion for pumping a substrate with the help of a chemical reaction may be related to the degree of coupling by using Eqn (9.57)... 

The role of adenosine triphosphate (ATP) in cells is to act as the short-term energy source. The function of the hydrolysis of ATP is to couple with non-spontaneous reactions, for example polymerization, and provide sufficient free energy to make them spontaneous (Chapter 24 on the accompanying website). 

Ligases Formation of C-C, C-S, C-0, and C-N bonds by condensation reactions, coupled to hydrolysis of ATP (adenosine triphosphate)... 

An important feature of biochemical reactions of metabolism and respiration is the coupling of pairs of reactions, which can result in the driving of a nonspontaneous reaction by the progress of a spontaneous reaction. The hydrolysis of adenosine triphosphate (abbreviated by ATP) to form adenosine diphosphate (abbreviated by ADP) and phosphoric acid (abbreviated by P) is shown in Figure 7.3. This is a spontaneous reaction that drives a number of usehil reactions in various organisms. 

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