Analysis of peptidase activities of a cathepsin B-like (TcoCBc1) from Trypanosoma congolense

Autor(es)

Oliveira, Lilian C. G. ^[1] ; Okamoto, Debora N. ^[1] ; Oliveira, Juliana R. ^[1] ; Kondo, Marcia Y. ^[1] ; Gouvea, Iuri E. ^[1] ; Biteau, Nicolas ^[2] ; Baltz, Theo ^[2] ; Murakami, Mario T. ^[3] ; Juliano, Luiz ^[1] ; Juliano, Maria A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Escola Paulista Med, Dept Biofis, BR-0444040 Sao Paulo - Brazil

^[2] Univ Bordeaux Segalen, CNRS, UMR 5234, F-33000 Bordeaux - France

^[3] Ctr Nacl Pesquisas Energia & Mat, Lab Nacl Biociencias, BR-13083970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS; v. 1844, n. 7, p. 1260-1267, JUL 2014.
• Citações Web of Science: 1

Resumo

The substrate specificity of TcoCBc1 was evaluated using two internally quenched fluorescent peptide libraries with randomized sequences designed to detect carboxydipeptidase (Abz-GXXZXK(Dnp)-OH) and endopeptidase (Abz-GXXZXXQ-EDDnp) activities at acidic and neutral pHs, respectively. All the data obtained with TcoCBc1 were compared with those of human cathepsin B, including the pH profiles of the hydrolytic reactions. The most relevant observation is the preference of TcoCBc1 for substrates with a pair of acidic amino acids at positions P-2 and P-1 for its carboxydipeptidase activity and the well acceptance for E and D at P-1 position for endopeptidase activity. These peculiar preferences for negatively charged groups of TcoCBc1 and its requirements for carboxydipeptidase activity were also observed on Abz labeled analogues of bradykinin (Abz-RPPG(down arrow)FSAFR-OH, Abz-RPPG(down arrow)FS(down arrow)AF-OH, Abz-RPPG(down arrow)DE(down arrow)AF-OH) and angiotensin I (Abz-DR(down arrow)VYIHAFHL-OH), where l indicates the cleavage site. TcoCBc1 was modeled based on the atomic coordinates of the cathepsin B from Trypanosoma brucei and the positively charged environment in TcoCBc1 catalytic site contrasts with the negatively charged environment in human cathepsin B. The preferences of S-1 and S-2 subsites of TcoCBc1 for acidic amino acids have to be taken into consideration for future studies of physiological roles of TcoCBc1 as for instance in apoptotic processes of Trypanosoma congolense. (C) 2014 Elsevier B.V. All rights reserved. (AU)

• Processo FAPESP: 12/50191-4 - Síntese, estudo cinético e aplicações de substratos e inibidores de enzimas proteolíticas
• Beneficiário: Maria Aparecida Juliano
• Modalidade de apoio: Auxílio à Pesquisa - Temático