EBIProteins Get Structural Features

Get secondary structure annotations for a protein from the EBI Proteins API. Returns helix, beta strand, and turn assignments mapped to the UniProt protein sequence. These are derived from experimental 3D structures and mapped to the canonical sequence, providing a comprehensive secondary structure profile. Example: P04637 (TP53) returns 40 structural features including helices (residues 19-29, 165-172, etc.), strands (residues 112-114, 141-143, etc.), and turns.