Ligand Expo Downloads

Chemical component dictionaries

SMILES/InChI data files:

Chemical component coordinate data files1:

PDB and chemical component identifier correspondences

Chemical component counting statistics

Downloading experimental coordinates for a particular chemical component1:

Since all chemical component dictionary entries follow a specific naming convention, you can easily skip searching and download the coordinates by entering the correct URL. The URL template is:



[1] Notes of files names: to uniquely identity experimental coordinate files the following underscore delimited coding scheme has been used:

PDB ID _ Component ID _ Model No. _ Chain ID _ Residue No. _ mmCIF Sequence No. _ mmCIF Asym ID _ Disorder Flag _

For example, the file name: 1pk8_ATP_1_B_801__R_D_.icif

Identifier Value
PDB ID 1PK8
Component/residue code  ATP
Model number1 (default)
Chain IDB
Residue number801
mmCIF sequence number   not applicable
mmCIF Asym ID R
Disorder FlagD (modeled with disorder)