Concept explainers
It is observed that as temperature is increased, most protein molecules go from their defined, folded state into a random-coil, denatured state that exposes more hydrophobic surface area than is exposed in the folded state.
a. Given what you have learned so about
b. Sometimes, however, proteins as temperature is decreased. How might this be explained? (Hint: Consider Problem 8)
7. Assume that some protein molecule, in its folded native state, has one favored conformation. But when it is denatured, it becomes a “random coil,” with many possible conformations.
a. If we only consider the entropy for the protein, what must be the sign of
b. How will the contribution of
8. When a hydrophobic substance like a hydrocarbon is dissolved in water, a clathrate cage of ordered water molecules is formed about it (see Figure 2.14). If we consider only the effects on water, what do you expect the sign of
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