Please explain in detail how to determine the answer If a p

Please explain in detail how to determine the answer :

If a part of a protein has sequence of GLEDKSA and forms one continuous -helix, which amino acid is the carbonyl of glycine non-covalently boned to?

Solution

Answer:

Amino group of K(lysine) is bonded to carbonyl of glycine by hydrogen bond.

In the alpha helix the N-H group of an amino acid forms a hydrogen bond with the C=O group of the amino acid four residues earlier. This is the most prominent characteristic of an -helix.