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UniProtKB Accession Number(s)

Search for structures by UniProtKB Accession Number, the unique identifier of an entry in the UniProtKB sequence database.

The UniProt Knowledgebase (UniProtKB) is the central database for sequences and functional annotations of proteins. The UniProtKB accession number is the unique alphanumeric identifier of each entry in UniProtKB.

A PDB structure may contain several chains, i.e. several separate macromolecules, and UniProtKB annotations in the PDB are provided at the chain level. The vast majority of protein chains in the PDB are annotated with a UniProtKB accession number. A search of the PDB by UniProtKB accession numbers is a query for structures that contain a chain that has been annotated with one of the accession numbers.

One or more UniProtKB accession numbers can be typed or copied and pasted in the search box. Multiple accession numbers can be separated by commas or white space, including line breaks.


  1. Enter P69905 into the text box. Press "Result Count" to preview the number of chains in the PDB that have been annotated with this UniProtKB accession number. Press "Submit Query" to retrieve the results. On the Query Results Browser page, click on the PDB ID, thumbnail image, or title of any structure to load its Structure Summary page. The UniProtKB accession number can be found on the "Sequence" tab.