A second endopeptidase from?Scytalidium lignicolum?(see scytalidopepsin A) that is insensitive to pepstatin and methyl 2-diazoacetamidohexanoate. 1,2-Epoxy-3-(p-nitrophenoxy)propane reacts with Glu53, which replaces one of the aspartic residues at the active centre. One of the smallest aspartic endopeptidases active as the monomer, with?Mr?22,000. Similarly inhibitor-resistant endopeptidases are found in the basidiomycetes?Lentinus edodes?[1] and?Ganoderma lucidum?[3], and in?Polyporus tulipiferae?[4], a second endopeptidase distinct from polyporopepsin, but these are of typical aspartic endopeptidase size,?Mr?about 36,000. Type example of peptidase family?G1.
Cofactor
History
Reactions
Hydrolysis of proteins with broad specificity, cleaving 24-Phe-|-Phe-25, but not 15-Leu-|-Tyr-16 and 25-Phe-|-Tyr-26 in the B chain of insulin.
