Stability in a folded protein is a balance between the stabilising (mainly hydrophobic) interactions and the tendency towards destabilisation caused by the loss of conformational entropy as the protein adopts the unfolded form.                what is the meaning of these sentences?what is meant by hydrophobic interactions and conformational entropy?hydrophobic interactions between what?

The entropy of a system is the measure of the degree of randomness or disorderliness in the system. When a molecule (protein in this case) undergoes a number of conformations (changes or rearrangements in shape by folding and unfolding), we term it as conformational entropy.

Proteins undergo hydrophobic (water-repelling) interactions to remain stable and biologically active. They play a role in the folding of proteins as they decrease their area and unwanted interaction with water. Hydrophobic interactions are between water and protein.

Both these factors- Conformational entropy and hydrophobic interaction together constitute stability in the folded protein.

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