SWISS-PROT, provided by the Swiss Institute of Bioinformatics, is a "curated protein sequence database" that provides, with minimal redundancy and "a high level of integration with other databases," descriptions of "the function of a protein, its domains structure, post-translational modifications" and variants, as well as a host of other information. Access to the SWISS-PROT database is available via "description or identification (any word in the DE, OS, OG, GN and ID lines)," by accession number (AC line), author (RA line), citation (RL line), or full text search. Lengthy returns offer information in several dozen fields, including taxonomic hierarchy, journal references, and sequence information.