Reaction: Release of an N-terminal L-arginine from a protein with only minimal activity against other amino acids. L-Arg-7-amido-4-methylcoumarin is the best artificial substrate.
Other name(s): arginyl aminopeptidase PH1704; PH1704; PfpI peptidase; C56.001 (Merops Identifier)
Comments: The enzyme from the archaeon Pyrococcus horikoshii OT3 is thermostable. In that enzyme Cys100 is the nucleophile responsible for the proteolytic activity, while Tyr120 regulates the catalytic conformation of Cys100 through a hydrogen bond, thereby affecting enzyme activity. The activity with L-Arginine is 90-300 times higher than with other N-terminal amino acids. The enzyme shows low endopeptidase activity.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:
References:
1. Du, X., Choi, I.G., Kim, R., Wang, W., Jancarik, J., Yokota, H. and Kim, S.H. Crystal structure of an intracellular protease from Pyrococcus horikoshii at 2-Å resolution. Proc. Natl. Acad. Sci. USA 97 (2000) 14079-14084. [PMID: 11114201]
2. Zhan, D., Han, W. and Feng, Y. Experimental and computational studies indicate the mutation of Glu12 to increase the thermostability of oligomeric protease from Pyrococcus horikoshii. J Mol Model 17 (2011) 1241-1249. [PMID: 20711794]
3. Zhan, D., Bai, A., Yu, L., Han, W. and Feng, Y. Characterization of the PH1704 protease from Pyrococcus horikoshii OT3 and the critical functions of Tyr120. PLoS One 9 (2014) e103902. [PMID: 25192005]