Reaction: Milk clotting activity. Preferential cleavage of Gly8Ser in B chain of insulin most rapidly, followed by Leu11Val, Cys(SO3H)19Gly and Phe24Phe. No action on Ac-Phe-Tyr(I)2.
Other name(s): Dictyostelium discoideum aspartic proteinase; Dictyostelium discoideum aspartic proteinase E; Physarum flavicomum aspartic proteinase; Physarum polycephalum acid proteinase; Physarum aspartic proteinase; physaropepsin
Comments: Belongs in peptidase family S53. From the slime mold Physarum polycephalum. Is not inhibited by pepstatin, but is blocked by methyl 2-diazoacetamidohexanoate. Closely similar enzymes are found in Dictyostelium discoideum and P. flavicomum. Formerly included in EC 18.104.22.168.
Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, CAS registry number: 94949-28-7
1. Henney, H.R. and Tavana, G. Purification and some properties of an intracellular acid (carboxyl) proteinase from differentiating haploid cells of Physarum flavicomum. Exp. Mycol. 6 (1982) 161-170.
2. Murakami-Murofushi, K., Hiratsuka, A. and Ohta, J. A novel acid protease from haploid amoebae of Physarum polycephalum, and its changes during mating and subsequent differentiation into diploid plasmodia. Cell Struct. Funct. 9 (1984) 311-315.
3. North, M.J. and Whyte, A. Purification and characterization of two acid proteinases from Dictyostelium discoideum. J. Gen. Microbiol. 130 (1984) 123-134.
4. Wlodawer, A., Li, M., Gustchina, A., Oyama, H., Dunn, B.M. and Oda, K. Structural and enzymatic properties of the sedolisin family of serine-carboxyl peptidases. Acta Biochim. Pol. 50 (2003) 81-102. [PMID: 12673349]
5. Nishii, W., Ueki, T., Miyashita, R., Kojima, M., Kim, Y.T., Sasaki, N., Murakami-Murofushi, K. and Takahashi, K. Structural and enzymatic characterization of physarolisin (formerly physaropepsin) proves that it is a unique serine-carboxyl proteinase. Biochem. Biophys. Res. Commun. 301 (2003) 1023-1029. [PMID: 12589815]