Hirudin (54-65), sulfated

This is amino acids 54 to 65 fragment of sulfated hirudin, a 65-residue peptide. Hirudin is found in the saliva of the leech Hirudo medicinalis. This sulfated peptide binds tightly to anion-binding exosite I of thrombin, but does not inhibit hydrolysis of synthetic peptide substrates.