Evolutionary Classification of Protein Domains

ECOD is a hierarchical classification of protein domains according to their evolutionary relationships. Only proteins with experimentally determined spatial structures from the PDB database are currently classified in ECOD. Compared with other classification databases, such as SCOP and CATH, ECOD emphasizes on distant evolutionary relationships and updates every week to include new structures released in PDB. Due to the delay of PDB FTP release and time needed to classify new domains, ECOD usually falls two to three weeks behind the PDB.