In α – helix the bonding occurs between oxygen of carbonyl group of one amino acid and hydrogen of amino group of

In an α-helix structure, the bonding occurs between the oxygen atom of the carbonyl group of one amino acid and the hydrogen atom of the amino group of another amino acid. Here are the steps:

1. The α-helix is a common secondary structure in proteins. It is a right-handed coiled or spiral conformation, in which every backbone N-H group donates a hydrogen bond to the backbone C=O group of the amino acid located three or four residues earlier along the protein sequence.

2. The carbonyl (C=O) group of one amino acid is involved in this bonding. The carbonyl group is a super functional group present in all amino acids, peptides, and proteins. The carbonyl group consists of a carbon atom double-bonded to an oxygen atom.

3. The amino group (-NH2) of another amino acid, specifically the one located three or four residues earlier in the sequence, is also involved in the bonding. The amino group consists of a nitrogen atom attached by single bonds to hydrogen atoms.

4. A hydrogen bond forms between the oxygen atom of the carbonyl group of one amino acid and the hydrogen atom of the amino group of the other amino acid. This hydrogen bond is what holds the spiral α-helix structure together.

5. The specific pattern of hydrogen bonding produces a helix with the repeating pattern of backbone atoms, which is the characteristic of the α-helix structure.

6. This process repeats along the length of the polypeptide chain, causing it to take on a coiled, spring-like shape. This is the α-helix structure, one of the most common structures found in proteins.