Four levels of structure — hemoglobin, click through
One real structure throughout: PDB 4HHB, human deoxyhemoglobin (Fermi & Perutz, 1984). Levels 1–3 follow just the alpha chain (chain A); quaternary zooms out to reveal all four chains assembling around their heme groups. Transitions are animated — the camera and the representation both morph between levels.
Primary structurereal 4HHB
what you're looking at
The raw sequence — a string of amino acids with no folding information applied.
who works at this level
ESM, ProtBERT
This is hemoglobin's alpha chain (chain A of 4HHB) with all folding information stripped from the rendering — just the backbone trace in sequence order. Nothing about helices or the 3D pack is shown yet.