Final answer:
The formation of α-helices or β-sheets as a result of hydrogen bonding comprises a protein's between carbonyl and amino groups in the peptide backbone.
Step-by-step explanation:
Proteins can form alpha-helices or beta-sheets as a result of hydrogen bonding between carbonyl and amino groups in the peptide backbone. An alpha-helix is a secondary structure where the polypeptide chain twists into a helical shape, with hydrogen bonds forming between amide hydrogens and carbonyl oxygens.
The hydrogen bonds stabilize the structure and give it rigidity. On the other hand, a beta-sheet is a secondary structure where the polypeptide chain folds into a pleated shape, with hydrogen bonds forming between different segments of the chain. This arrangement allows for parallel or antiparallel alignment of the segments.
The formation of alpha-helices and beta-sheets is influenced by the amino acid sequence. Certain amino acids have a propensity to form alpha-helices, while others have a propensity to form beta-sheets. For example, alpha-helices are often formed by amino acids with small side chains, such as alanine and leucine, while beta-sheets are often formed by amino acids with larger side chains, such as valine and isoleucine.
In proteins, alpha-helices and beta-sheets play important structural roles. The alpha-helix provides stability and rigidity to the protein, while the beta-sheet allows for flexibility and the formation of binding sites. These secondary structures are commonly found in globular and fibrous proteins.
So therefore proteins can form alpha-helices or beta-sheets as a result of hydrogen bonding between carbonyl and amino groups in the peptide backbone. The formation of these structures is influenced by the amino acid sequence. Alpha-helices provide stability, while beta-sheets allow for flexibility and the formation of binding sites.