What type of hydrogen bonds are found in antiparallel β-sheets?

Antiparallel β-sheets are characterized by the arrangement of polypeptide chains running in opposite directions, which allows for the formation of more efficient hydrogen bonds between the backbone amide and carbonyl groups of the polypeptide strands. In these structures, the hydrogen bonds formed are predominantly linear in nature. This linearity is crucial because it allows for optimal overlap between the electron clouds of the donor and acceptor groups, leading to stronger and more stable hydrogen bonds.

The linear hydrogen bonding pattern is a key factor in the stability and regularity of the antiparallel β-sheet structure, as it maximizes the energy favorable interactions. Such hydrogen bonds are typically formed between a hydrogen atom bonded to a nitrogen atom (from the amide group) and the oxygen atom of the carbonyl group in the adjacent strand. This arrangement is essential for the integrity of protein secondary structures and impacts the overall folding and function of proteins.

The other types of bonds mentioned, such as bent or covalent hydrogen bonds, do not properly describe the nature of hydrogen bonds in antiparallel β-sheets. Bent hydrogen bonds occur in other contexts where there is less optimal alignment. Covalent bonds are a different type of interaction entirely, involving the sharing of electrons rather than