rd
23 Congress of the International Union for Biochemistry and Molecular Biology
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44 Annual Meeting of the Brazilian Society for Biochemistry and Molecular Biology
th
th
Foz do Iguaçu, PR, Brazil, August 24 to 28 , 2015
TRYPSIN AS A MODEL FOR THE STUDY OF THERAPEUTIC PROTEASE
INHIBITORS
Teixeira, E. M. G. F. 1,2; Resende, G. O.3, Caldeira, A. S. P.1, Silva-López, R. E.1
1
Departamento de Produtos Naturais, Farmanguinhos, Fundação Oswaldo Cruz
(FIOCRUZ), Rio de Janeiro, Brazil;
2
3
Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Departamento de Química Orgânica, Instituto Federal do Rio de Janeiro (IFRJ),
Rio de Janeiro, Brazil
Introduction: Trypsin is the most studied protease in nature and is the major
representative of the serine protease class. Their activities are modulated by protease
inhibitors that bind specifically to the active site and regulate many physiological
processes as well as it can be used in the treatment of various diseases. Objectives:
Study the effect of synthetic and natural serine protease inhibitors on kinetic
characteristics of porcine and bovine trypsin activity. Material and Methods: Organic
compounds with tartaric acid and D/L valine isomers (T1 and T1´), arrays of valine and
leucine (PP69 and P70) or valine and phenylalanine (P71), benzamidine,
phenylmethanesulfonyl fluoride (PMSF) and N-tosyl-L-lysine chloromethyl ketone
(TLCK) were used as synthetic inhibitors in the reaction of trypsin and N--tosyl-Larginine methyl ester (L-TAME) as substrate. Results and Discussion: Tris-HCl pH
8.2, without calcium, was the best buffer for both porcine and bovine trypsin using LTAME as substrate. The calcium ions had a negative effect on enzymatic activity. The
KM values of trypsin using L-TAME as substrate were 1.148 to 1.785 mM. Bovin trypsin
is more responsive than porcine trypsin to tartaric derivates inhibitors and the
commercial synthetic serine protease inhibitors than porcine trypsin. The best inhibition
for both proteases was obtained using TLCK, which has a lysine residue at P1 site.
Conclusions: Trypsin-like serine proteases are the most studied proteases in the
nature, so their inhibitors are also. Synthetic and natural inhibitors have been employed
in treatment of many diseases or conditions. So, the present work showed some results
about trypsin inhibition and studies on natural products are being carrying out in this
direction.
Brazilian Society for Biochemistry and