Dual function macrocyclase-peptidase involved in the biosynthesis of the highly toxic amanitin toxin family of macrocycles (PubMed:20889720). Cleaves peptide bonds on the C-terminal side of prolyl residues (By similarity). The enzyme first removes 10 residues from the N-terminus of a 35-residue substrate (By similarity). Conformational trapping of the 25 amino-acid peptide forces the enzyme to release this intermediate rather than proceed to macrocyclization (By similarity). The enzyme rebinds the 25 amino-acid peptide in a different conformation and catalyzes macrocyclization of the N-terminal eight residues (By similarity). Hydrolysis of Pro-|-Xaa >> Ala-|-Xaa in oligopeptides. Monomer. Expressed in the pileus (cap) and lamellae where it colocalizes with amanitin (PubMed:20889720). Belongs to the peptidase S9A family.