Reaction: Cleavage of amide substrates following the basic amino acids Arg or Lys at the P1 position, with a preference for Arg over Lys
Other name(s): KLK8; PRSS19; human kallikrein 8; hK8; mK8; ovasin; tumor-associated differentially expressed gene 14; TADG-14; NP; neuropsin
Comments: The enzyme is activated by removal of an N-terminal prepropeptide [2,4]. The highest amidolytic activity is observed using Boc-Val-Pro-Arg7-amido-4-methylcoumarin, which is a substrate of α-thrombin [2,4]. Substrates lacking basic amino acids in the P1 position are not cleaved . The enzyme degrades casein, fibronectin, gelatin, collagen type IV, fibrinogen, and high-molecular-mass kininogen  and is associated with diseases such as ovarian cancer and Alzheimer's disease . Belongs in peptidase family S1A.
Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 171715-15-4
1. Chen, Z.L., Yoshida, S., Kato, K., Momota, Y., Suzuki, J., Tanaka, T., Ito, J., Nishino, H., Aimoto, S., Kiyama, H. and Shiosaka, S. Expression and activity-dependent changes of a novel limbic-serine protease gene in the hippocampus. J. Neurosci. 15 (1995) 5088-5097. [PMID: 7623137]
2. Shimizu, C., Yoshida, S., Shibata, M., Kato, K., Momota, Y., Matsumoto, K., Shiosaka, T., Midorikawa, R., Kamachi, T., Kawabe, A. and Shiosaka, S. Characterization of recombinant and brain neuropsin, a plasticity-related serine protease. J. Biol. Chem. 273 (1998) 11189-11196. [PMID: 9556608]
3. Rajapakse, S., Ogiwara, K., Takano, N., Moriyama, A. and Takahashi, T. Biochemical characterization of human kallikrein 8 and its possible involvement in the degradation of extracellular matrix proteins. FEBS Lett. 579 (2005) 6879-6884. [PMID: 16337200]
4. Kishi, T., Cloutier, S.M., Kündig, C., Deperthes, D. and Diamandis, E.P. Activation and enzymatic characterization of recombinant human kallikrein 8. Biol. Chem. 387 (2006) 723-731. [PMID: 16800733]