superimpose protein 3D structures Alphabet of protein structures. Display, analyse and superimpose protein 3D structures WWW-based course teaching elementary protein bioinformatics Critical Assessment of Structure Prediction (CASP) Structural Classification of Proteins (SCOP) CATH Protein Structure Classification DALI/FSSP software and database of superposed protein structures TOPOFIT-DB Invariant Structural Cores between proteins PDBWiki — PDBWiki Home Page – a website for community annotation of PDB structures. Protein structure 3