Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Alpha helices are a type of secondary protein structure where the polypeptide chain is coiled like a spring, resembling a spiral staircase. This structure is stabilized by hydrogen bonds between amino acids in the chain.
Related terms
Hydrogen bonds: Weak chemical bonds formed between the positively charged hydrogen atom of one molecule and the negatively charged atom (usually oxygen or nitrogen) of another molecule.
Tertiary level of protein structure: The overall three-dimensional shape of a protein, formed by interactions between different regions of the polypeptide chain.
Quaternary level of protein structure: The arrangement and interaction of multiple polypeptide chains to form a functional protein complex.