4.3 Protein folding is driven by the formation of a hydrophobic core

hydrophobic core

When secondary structural elements pack against each other in folded proteins, they bring together the hydrophobic sidechains that form the _________ ______

stability

the _______ of the folded structure results primarily from the preference of the hydrophobic sidechains to be clustered together and away from water.

van der Waals, hydrogen, ionic

Smaller contributions to stability of the folded structure are made by the favorable _______ ________ ______ interactions between atoms in the folded state (see Section 6.16), as well as by _______ bonds and _____ interactions.

hydrophobic effect

the _________ _______, and not hydrogen-bond formation, is the dominant factor that drives the folding of protein molecules

secondary

In an unfolded protein chain the water molecules for hydrogen bonds with the backbone -NH and -C=O groups. The chains fold up to form a beta sheet or alpha helix. The hydrogen bonds with water are replaced by hydrogen bonds formed within the ______ structural elements

unfolded

One consequence of the importance of the hydrophobic effect in protein folding is that the individual secondary structural elements do not usually have a very stable structure by themselves when the protein is _____.

fragments

Isolated _______ of proteins do no usually have stable structures