Biochemical aspects of a serine protease from Caesalpinia echinata Lam. (Brazilwood) seeds: a potential tool to access the mobilization of seed storage proteins.
Several proteins have been isolated from seeds of leguminous, but this is the first report that a protease was obtained from seeds of Caesalpinia echinata Lam., a tree belonging to the Fabaceae family. This enzyme was purified to homogeneity by hydrophobic interaction and anion exchange chromatographies and gel filtration. This 61-kDa serine protease (CeSP) hydrolyses H-D-prolyl-L-phenylalanyl-L-arginine-p-nitroanilide (K(m) 55.7 μM) in an optimum pH of 7.1, and this activity is effectively retained until 50 °C. CeSP remained stable in the presence of kosmotropic anions (PO(4) (3-), SO(4) (2-), and CH(3)COO(-)) or chaotropic cations (K(+) and Na(+)). It is strongly inhibited by TLCK, a serine protease inhibitor, but not by E-64, EDTA or pepstatin A. The characteristics of the purified enzyme allowed us to classify it as a serine protease. The role of CeSP in the seeds cannot be assigned yet but is possible to infer that it is involved in the mobilization of seed storage proteins.
Department of Biochemistry, Universidade Federal de São Paulo, 04044-020 São Paulo, Brazil.
Priscila
P
Praxedes-Garcia
Ilana
I
Cruz-Silva
Andrezza Justino
AJ
Gozzo
Viviane
V
Abreu Nunes
Ricardo José
RJ
Torquato
Aparecida Sadae
AS
Tanaka
Rita de Cássia
Rde C
Figueiredo-Ribeiro
Yamile Gonzalez
YG
Gonzalez
Mariana da Silva
Mda S
Araújo
D004789:Enzyme Activation; D004795:Enzyme Stability; D055314:Seed Storage Proteins / Q000032:analysis / Q000737:chemistry*; D012639:Seeds / Q000201:enzymology*; D057057:Serine Proteases / Q000032:analysis / Q000737:chemistry*
D055314:Seed Storage Proteins; D057057:Serine Proteases