Secondary Protein Structure Practice Problems

In terms of protein structure, what is a secondary structure, and which molecular bonds or interactions contribute to stabilizing this level of structure?

Fibrous proteins are insoluble in water, while globular proteins are soluble. Do you expect valine (Val), an amino acid, to be found on the surface of a fibrous or globular protein?

True or False: Globular proteins, unlike fibrous proteins, are water-insoluble and composed of compact, non-repeating structures.

True or false: In the β-sheet in the figure below, covalent bonding between specific atoms is the type of bonding responsible for the sheet formation.

Sketch the structural formula of the pentapeptide Tyr-Gly-Gly-Phe-Met in linear form and show the hydrogen bonding that stabilizes the structure if it forms an α-helix.

A protein has the primary structure Thr-His- Pro-Tyr-Pro-Leu-Pro-Pro -Glu-Thr. Which amino acid is responsible for its very kinked helix secondary structure?

True or false: The α-helix has 8 backbone carbon and nitrogen atoms included in the loop between the hydrogen atom of an amide and the carbonyl oxygen to which it is hydrogen bonded. Use the image of the α-helix below for reference.