Heliliste

Heliliste is a term used in structural biology and related fields to denote a curated catalog or database of helix-based structural motifs. In practice, a heliliste compiles instances of helical segments found in macromolecules such as proteins and nucleic acids, as well as in synthetic nanostructures, and provides standardized descriptors to enable cross-study comparison of their geometry and context.

Entries in a heliliste typically record the source molecule, the chain, the residue or nucleotide range, and geometric properties such as handedness (right- or left-handed), pitch, rise per turn, turn count, and helix type (alpha, 3-10, pi, or user-defined variants). Additional annotations may include backbone dihedral angles, solvent exposure, secondary-structure context, and functional notes.

First proposed in the late 1990s as structural data became more abundant, heliliste evolved into a general concept for organizing helical motifs. It is now maintained by community standards groups and sometimes by institutional databases, with cross-links to major structure repositories and file formats such as PDB and mmCIF.

Applications include comparative analysis of helices across protein families, annotation of structural databases, and guidance in protein design or nanostructure fabrication that relies on predictable helical geometry. Limitations include incomplete coverage for low-resolution structures, variability in motif definitions, and ongoing efforts to harmonize naming and classification standards.

See also: helix, protein structure, structural motif, structural biology databases, and helical nanostructures.