Pyrrolidone-carboxylate peptidase (EC 22.214.171.124) (PYRase) (also known as
pyroglutamyl peptidase) is the enzyme that selectively removes pyroglutamate
(pGlu) from the N-terminus of proteins and peptides.
In bacteria and archebacteria PYRase (gene pcp) is a protein of 22-25 kD. It
is a cysteine protease with a Cys-His-Glu catalytic triad [1,2]. We developed
two signature patterns that respectively include the glutamate and cysteine
active site residues.
These proteins belong to family C15 in the classification of peptidases
December 2004 / Pattern and text revised.
PROSITE methods (with tools and information) covered by this documentation:
Singleton M.R., Isupov M., Littlechild J.
X-ray structure of pyrrolidone carboxyl peptidase from the hyperthermophilic archaeon Thermococcus litoralis.
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