Protein Viewer
Load proteins by PDB ID or upload `.pdb`, inspect amino-acid sequence, style individual chains, and right-click selected sequence regions to restyle or hide them.
Chains
Amino Acid Sequence
Drag across residues to select a region. Right-click selection to restyle or hide only that segment.
Exploring a protein structure
The Protein Data Bank (PDB) holds experimentally determined 3D structures of proteins, nucleic acids, and their complexes. Each entry has a four-character ID, for example 1CRN for crambin, a small plant protein often used in examples, or 4HHB for human deoxyhaemoglobin.
Choosing a display style
- Cartoon: shows secondary structure, with helices as ribbons or spirals and β-strands as arrows. Best for seeing the overall fold.
- Stick: shows individual bonds. Best for side chains, ligands, and active sites.
- Sphere: space-filling atoms that show shape and packing.
- Line: lightweight wireframe, useful for large structures.
Working with chains and sequences
Many structures contain several chains, for example haemoglobin's two α and two β chains. Style each chain differently to see how they pack together. Selecting a stretch of the amino-acid sequence and restyling it is a quick way to highlight a binding loop or a mutation site for a figure.
Tip: export PNG for slides, or PDB/XYZ/OBJ when you need the coordinates or a mesh in another program. To turn a bound ligand into SMILES, see PDB to SMILES.