Finding matches for a specific peptide sequence is important for protein identification in proteomics studies. It is also important for sequence-based protein retrieval as peptide sequences can often be too short for effective BLAST search. The Protein Information Resource, a UniProt consortium partner, has hosted a Peptide match service for over a decade. This popular tool is now also available directly through the UniProt interface! It can be accessed from the 'Peptide search' link in the UniProt website header.
All you need to provide as input is a peptide sequence at least three amino acids long. Optionally, you can choose to restrict the search to a specific taxonomic group and/or you can specify whether you would like the tool to treat Isoleucine and Leucine as equivalent.
The Peptide search results display proteins that have exact match to the query sequence in a table with filters on the left hand side. The table contains an additional column titled 'Peptide search:...', which shoes the sequence matched and the sequence position where the match begins in the target sequence. Each peptide search job is assigned a unique identifier that can be used to retrieve the results back from UniProt for up to seven days by simple pasting it back into the main search box or by bookmarking the peptide search results URL.
Try out this new tool now and let us know what you think!