Protein structure and function

Question 1

What types of bonds hold together secondary structure of a protein?

Answer 1

H-bonds, Van Der Waals interactions, and salt bridges.

Question 2

Where does hydrogen bonding occur in alpha helices and beta sheets?

Answer 2

in alpha helices it occurs between the amino and carbonyl groups of successive amino acids in the helix.

in beta sheets it occurs between adjacent amino and carbonyl groups

Question 3

How are multi-subunit proteins held together?

Answer 3

non-covalent bonding or covalent disulfide and isopeptide bonds.

Question 4

What are chaperone proteins and how do they work?

Answer 4

These proteins discourage inappropriate folding of proteins by reducing the local energy required (conformation energy dips and elevates on its way down) for protein to move on to its final lowest energy conformation.

Question 5

Why are disulfide bridges only found in the membrane or outside of the cell?

Answer 5

Because they are a result of oxidation and would be reduced by the reducing environment of the cytoplasm and nucleus.