InterPro is an integrated database of predictive protein "signatures" used for the classification and automatic annotation of proteins and genomes. InterPro classifies sequences at superfamily, family and subfamily levels, predicting the occurrence of functional domains, repeats and important sites. InterPro adds in-depth annotation, including GO terms, to the protein signatures.
The Protein database is a collection of sequences from several sources, including translations from annotated coding regions in GenBank, RefSeq and TPA, as well as records from SwissProt, PIR, PRF, and PDB. Protein sequences are the fundamental determinants of biological structure and function.
PROSITE consists of documentation entries describing protein domains, families and functional sites as well as associated patterns and profiles to identify them.
Image: Molecular structure of protein registered with 1jy6 code. Jawahar Swaminathan and MSD staff at the European Bioinformatics Institute. Public Domain. Wikimedia Commons.