Many Biological macromloecules undergo a transtition called denaturation. Denatu
ID: 978999 • Letter: M
Question
Many Biological macromloecules undergo a transtition called denaturation. Denaturation is a process whereby a structred, biological active molecule, called the native form, unfolds or becomes unstructured and biologically inactive, The equilibrium is native (folded) riversible denatured (unfolded) For a protein at P^H - 2 the enthalpy change at 298 K associated with denaturation is delta H^degree =418.0KJ mol^-1 and the entropy change at 298 K is delta S^degree = 1.30 KJ^-1 mol^-1. Calculate the Gibbs energy change for the denaturation of the protein at P^H = 2 and T = 310. K. Assume the enthaply and entropy are temperature-independent between 298 K and 303 K. Calculate the equilibrium constant for the denatruation of the protein at P^H 2 and T = 310 .K. Based on your answer for parts (a) and (b), is the protein structurally stable at P^H 2 and T = 310. K.Explanation / Answer
a)
delta G = delta H - T* delta S
=418 - 310*1.3
= 15 KJ/mol
Answer: 15 KJ/mol
b)
delta G = 15 KJ/mol = 15000 J/mol
use:
delta G = -R*T*ln Kc
15000 = -8.314* 310 * ln Kc
Kc = 2.96*10^-3
Answer: 2.96*10^-3
c)
since delta G is positive and also Kc is less than 1, the given reaction is not favourable.
So native (fold) form is more stable
yes protein is structurally stable