Exam 3: Proteins I

Which of the following structures shows the prevalent form of histidine at pH 5?

The predominant noncovalent interaction seen in $\alpha$ helices and $\beta$ sheets is _____.

During the initial synthesis of collagen molecules, _____ and _____ are most often incorporated into the growing protein.

Which one of the representations describes the oligopeptide shown below?

Which of the following atoms would be considered a hydrogen-bond donor in an $\alpha$ helix?

At pH 3, how many charged groups are present in the pentapeptide Ala-Asp-His-Ser-Lys?

The side chain of serine could interact with the side chain of _____ using a(n) _____.

In the following figure, which bond would be unable to rotate?

At a pH above its pK_a, the phenolic group of tyrosine is _____.

Which of the following interactions would be involved in quaternary structure?

At a pH above its pK_a, the R-group of Asp is _____.

The amino acid _____ is commonly phosphorylated.

Lysine can form a salt bridge by interacting with the side chain of _____.

Leucine has a _____ side chain; glutamate has a _____ side chain.

Proteins such as hemoglobin are known as _____ proteins because binding of a molecule to one site alters binding to other sites.

Which of the following amino acids has a positively charged side chain at pH 7.4?

Which of the following amino acids is generally absent from an $\alpha$ helix?

Which of the following structures shows the prevalent form of glutamic acid at pH 3? A. B. C. D.

Which of the following amino acids has a thiol group in its side chain?

The only observable regular secondary structures are $\alpha$ helices and $\beta$ sheets.