An -helix has the sequence: NH₃₊-Ser-Glu-Gly-Asp-Trp-Gln-Leu-His-Val-Phe-Ala-Lys-Val-Glu-COO-.The carbonyl oxygen (in the peptide bond) of the histidine residue is hydrogen bonded to the amide
Nitrogen of

Question

An

An -helix has the sequence: NH<sub>3+</sub>-Ser-Glu-Gly-Asp-Trp-Gln-Leu-His-Val-Phe-Ala-Lys-Val-Glu-COO-.The carbonyl oxygen (in the peptide bond) of the histidine residue is hydrogen bonded to the amide Nitrogen of A) Asp. B) Lys. C) Trp. D) Ala.

-helix has the sequence: NH₃₊-Ser-Glu-Gly-Asp-Trp-Gln-Leu-His-Val-Phe-Ala-Lys-Val-Glu-COO-.The carbonyl oxygen (in the peptide bond) of the histidine residue is hydrogen bonded to the amide
Nitrogen of

Quizplus · Accepted Answer

The question specifies that the carbonyl oxygen of histidine is hydrogen bonded to the amide nitrogen of another amino acid. The only amino acid in the sequence that has an amide nitrogen available for hydrogen bonding is lysine (Lys), which has an amide nitrogen in its side chain. Therefore, the best choice is B.

An -Helix Has the Sequence: NH3+-Ser-Glu-Gly-Asp-Trp-Gln-Leu-His-Val-Phe-Ala-Lys-Val-Glu-COO-

An -Helix Has the Sequence: NH₃₊-Ser-Glu-Gly-Asp-Trp-Gln-Leu-His-Val-Phe-Ala-Lys-Val-Glu-COO-