RCSB Protein Data Bank: Member of the wwPDB curates and annotates PDB data according to agreed upon standards.
CATH: Hierarchical classification of protein domain structures.
Thornton Group Services: Provides a list of services like the Catalytic Site Atlas (documents enzyme active sites) and ProFunc (sequence- and structure-based methods to help identify protein functions).
CASTp: Provides identification and measurements of surface accessible pockets as well as interior inaccessible cavities, for proteins and other molecules.
ConSurf: Projection of evolutionary conservation scores of residues on protein structures.
PocketDepth: Depth based algortihm for identification of ligand binding sites.
eF-site: Database for molecular surfaces of proteins' functional sites, displaying the electrostatic potentials and hydrophobic properties together on the Connolly surfaces of the active sites, for analyses of the molecular recognition mechanisms.