Question

How are alpha helices stabilized?

Answer 1

Alpha helix structure is a secondary structure of the proteins, this structure is a coiled structure in the bond formed between the carbon atom of the one amino-acid and oxygen atom of another amino-acid.

Complete step-by-step answer: Proteins are a set of macromolecules in which the alpha-amino acids are the monomers. So, the arrangement of the monomers or alpha-amino acids is in different manners. There are four types of structures: primary structure, secondary structure, tertiary structure, and quaternary structure.
The Alpha-helix structure is one of the types of secondary structure. In this structure, the polypeptide chains assume a result of hydrogen bonding. Scientist Linus Pauling in 1951 gave this theoretical explanation of the secondary structure of the protein.
The polypeptide chain has coiled up into a spiral structure in the right-handed alpha-helix structure. When they coil up, there is the formation of hydrogen bonding between the layers of the coil. Since amino acids have both carboxylic acid and amino group, the hydrogen bonding from between the oxygen atom of the carboxylic group of the upper layer and the hydrogen atom of the amino group of the lower layer, which helps it to remain in the coiled or spiral form.
Due to this formation of hydrogen bonding, the alpha helices are stable. The distance between one layer of the secondary structure and the next layer of the secondary structure is 54 pm.

Note: This alpha-helix structure of the protein is present as alpha-keratin in hair, nail, wool, skin, claws, etc, and in muscles is also present as myosin. Another secondary structure of the protein is the beta-pleated structure.