The Universal Protein Resource (UniProt), a collaboration between the European Bioinformatics Institute (EBI), the SIB Swiss Institute of Bioinformatics, and the Protein Information Resource (PIR), is comprised of three databases, each optimized for different uses. The UniProt Knowledgebase (UniProtKB) is the central access point for extensively curated protein information, including function, classification and cross-references. The UniProt Reference Clusters (UniRef) combine closely related sequences into a single record to speed up sequence similarity searches. The UniProt Archive (UniParc) is a comprehensive repository of all protein sequences, consisting only of unique identifiers and sequences.
The UniProt Knowledgebase (UniProtKB) has been created from Swiss-Prot, TrEMBL and PIR-PSD. It consists of two parts, one containing fully manually annotated records and another one with computationally analysed records awaiting full manual annotation. The two sections will be referred to as the Swiss-Prot section of the UniProt Knowledgebase (UniProtKB/Swiss-Prot) and TrEMBL section of the UniProt Knowledgebase (UniProtKB/TrEMBL), respectively. PIR-PSD release 80.0 of 31-Dec-2004 has been fully integrated into these sections. This was the last release of PIR-PSD.
UniProt (database directory location with all files included in the release, and commonly used database files in FASTA format)