Question

PLEASE PROVIDE CALCULATIONS

A protein can fold into four different conformations.

A) If the states are iso-energetic, and the system has 1 mole of protein equally mixed between the four states, what is the entropy change of forcing it all into a single confirmation on a per mole basis? (This might occur for example during the process of crystallization.)

B) Instead imagine that states B, C, D have a +1 kbT, +2 kbT, and +3 kbT energy increase compared to state A, respectively. What is the probability of finding the protein in each of the states?

C) For the system in part (B), now what’s the entropy change (on a per mole basis) of forcing the equilibrium mixture all to state A?

Answer 1

Iso energetic means having the same or constant amount of energy. A protein can fold into three different conformations (structures).

A. If the states are iso-energetic, and the system has one mole of protein equally mixed between three states, the entropy change of forcing it all into a single conformation on a per mole basis is that The entropy (degree of disorder or randomness in the system) obviously decrease compared to the previous state of protein confirmation.

B. The probability of finding the protein in each of the states is gradually decreases because, the stability of the confirmation changes gradually decreases with increase of the temperature. In this case, protein in state A has lower energy compared to state-B and state-C.

C.The entropy change of forcing the equilibrium mixture all to state A is decreased gradually because of more the protein in the state-A has low amount of energy compared to remaining two states.