Question

Part F Calculate the energy available from hydrolysis of ATP if the ATP/ADP ratio is 5:1, the inorganic phosphate concentration is 50 mM and the temperature is 37°C? (Assume AG' = -7.3 kcal/mol for ATP hydrolysis.) Express your answer as an integer. AG' = -10100 cal/mol Submi Previous Answers Correct

Answer 1

Part F: The hydrolysis of ATP gives ADP and Pi (inorganic phosphate) and free energy. The reaction of ATP hydrolysis is as follows: $ATP+H_{2}O\rightarrow ADP+Pi+energy$ .

Here the ratio of ATP to ADP is 5:1 and the concentration of inorganic phosphate is 50 mM= 5 $\times$ 10^-2 M. The standard free energy change, $\Delta G^{0'}$ = -7.3 kcal/mol = -7300 cal/mol, Temperature, T=37⁰C=(273+37)=310 K

So the free energy change from the hydrolysis of ATP is given by the equation,
AG = AGC + RT In (ADP][Pi] [АТР
or, $\Delta G^{'}=-7300+1.98\times 310\ln \frac{1\times 5\times 10^{-2}}{5}=-7300-2827=-10127 cal/mol$

Part I: The reaction of the synthesis of ATP requires the presence of ADP and Pi where ADP combines with Pi to form ATP. The reaction is as follows: $ADP+Pi+energy\rightarrow ATP+H_{2}O$ .

The ratio of ATP to ADP is 5:1; and the concentration of inorganic phosphate is 50 mM= 5 $\times$ 10^-2 M. The standard free energy change, $\Delta G^{0'}$ = -7.3 kcal/mol = -7300 cal/mol, temperature=25⁰C=(273+25)K=298 K.

So the free energy change for ATP synthesis is given by the equation,

$\Delta G^{'}=\Delta G^{0'}+RT\ln \frac{[ATP]}{[ADP][Pi]}$ or, $\Delta G^{'}=-7300+1.98\times 298\ln \frac{5}{1\times5\times 10^{-2}}=-7300+2717=-4583cal/mol$ .