Identify proteins using BLAST searches for peptide fragment sequencesGo to the National Ce...

Identify proteins using BLAST searches for peptide fragment sequences

Go to the National Center for Biotechnology Information web site at http://www.ncbi.nlm.nih.gov/. From the menu of Popular Resources on the right hand side, click on “BLAST”. Under the Basic BLAST heading on the new page that comes up, click on “protein blast”. In the Enter Query Sequence box at the top of the page that comes up enter the following sequence: NGMMKSSRNLTKDRCK. Confirm that the database under “Choose Search Set” is set on “nr” (nonredundant protein sequences), then click the BLAST button at the bottom of the page to see the results of your search. Next, enter this sequence from a different protein: SLQTASAPDVYAIGECA. Identify the protein from which this sequence was derived.