ID 3.4.21.67 DE endopeptidase So. AN E.coli cytoplasmic proteinase. CA Hydrolysis of proteins, but not Bz-Tyr-OEt, Ac-Phe-beta-naphthylester, CA or Bz-Arg-OEt. CC -!- Cytoplasmic peptidase. CC -!- Inhibited by Tos-Phe-CH2Cl, but not by Tos-Lys-CH2Cl. CC -!- Formerly EC 3.4.4.16 and EC 3.4.21.14. //