Phylogenetic Tree

Pacifastin inhibitor

Pacifastin is a family of serine proteinase inhibitors found in arthropods. Pacifastin inhibits the serine peptidases trypsin and chymotrypsin. All pacifastin members that have been characterized at the molecular level are precursor peptides composed of an N-terminal signal sequence followed by a precursor domain and a variable number of inhibitor domains.

--From Wikipedia