Helical wheel

Content sourced from Wikipedia, licensed under CC BY-SA 3.0.

A helical wheel is a simple circular diagram used to study alpha helices in proteins. It places the amino acids of a helical region around a circle, with about 100° between consecutive residues, so you’re effectively looking down the helix axis. The chart shows whether hydrophobic amino acids cluster on one side and polar, hydrophilic ones on the other. This amphipathic pattern is common in globular proteins, where one face points to the hydrophobic core and the opposite face faces the solvent. Helical wheels can also reveal patterns related to folding and docking, such as leucine zipper regions and coiled coils. The diagram is often called the Edmundson wheel, after its inventor. You can draw helical wheels with tools like HelixVis (R), HeliQuest (R), or the HELIQUEST web server.