Substrate specificity and physiological function of mammalian dipeptidases

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06997
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Functional biochemistry
• Research Institution: Osaka University
• Principal Investigator: Okumura Nobuaki 大阪大学, たんぱく質研究所, 准教授 (20224173)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: ジペプチド / カルノシン / ヒスチジン / βアラニン / 金属プロテアーゼ

Outline of Final Research Achievements

Dipeptides are produced and degraded in mammalian cells during protein turnover and digestion to obtain amino acids required for nutritional demands. In addition, some kinds of dipeptides such as carnosine are synthesized from amino acids in specific organs and play some specific roles as a bioactive molecule. We have previously found that a metallopeptidase CN2 hydrolyses several kinds of dipeptides including carnosine. In this study, we have determined the substrate specificity of CN2, and shown that CN2-Mn2+ and CN2-Zn2+ complexes have different substrate specificity. When substrate specificity in cultured cells was examined, it was more similar to that of the CN2-Zn2+ complex observed in in vitro enzyme assay. These results demonstrate the role of CN2 in the final step of protein and peptide breakdown.

Free Research Field

生化学