OBSOLETE. Catalysis of the cleavage of peptides after specific recognition of a C-terminal tripeptide, Xaa-Yaa-Zaa, in which Xaa is preferably Ala or Leu, Yaa is preferably Ala or Tyr, and Zaa is preferably Ala. Cleavage is at a variable distance from the C-terminus; a typical cleavage is -Ala-Ala-Arg-Ala-Ala-Lys-Glu-Asn-Tyr-Ala-Leu-Ala-Ala.