Biochemical characterization of the YBPCI miniprotein, the first carboxypeptidase inhibitor isolated from Yellow Bell Pepper (Capsicum annuum L). A novel contribution to the knowledge of miniproteins stability, Protein

COTABARREN, JULIANA; MARIANA TELLECHEA; FRANCESC X. AVILÉS; JULIA LORENZO; OBREGÓN, DAVID; OBREGÓN, W.D

PROTEIN EXPRESSION AND PURIFICATION

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2017

1046-5928

The cysteine-knot metallocarboxypeptidase inhibitors (MCPIs) arepeptides that contribute to control proteolytic activity, involved in storage,growth and maintenance of plants. Lately studies reported several MCPIs withpotential use in biomedical applications; as anti-cancer, anti-thrombotic, anti-malaricand anti-angiongenic agents. We report the isolation, purification, chemicalstability and biochemical characterization of a novel carboxypeptidase Ainhibitor (YBPCI) isolated from Capsicum annuum L. var. Yellow BellPepper, the first CKM of the species. We demonstrate the stability of YBPCI(IC50 = 0.40 µg/ml) to high temperatures, salt concentration and extreme pHvalues. MALDI-TOF/MS analysis detected a molecular weight of 4057 Da, and peptidemass fingerprint resulted in no matches with other protease inhibitors. In-vitro gastrointestinal digestionsubjecting YBPCI to pH 2 incubation and proteolytic attack resulted in completeinhibitory activity. To summarise, there are no reports to date ofCarboxypeptidase inhibitors in C. annuumspecies, giving our report much more relevance.