Artigo
Primary structure of Dioclea glabra trypsin inhibitor, DgTI, a Bowman-Birk inhibitor
Fecha
1999-08-11Registro en:
Biochemical and Biophysical Research Communications. San Diego: Academic Press Inc, v. 261, n. 3, p. 838-843, 1999.
0006-291X
10.1006/bbrc.1999.1099
WOS:000082014900050
Autor
Bueno, N. R.
Fritz, H.
Auerswald, E. A.
Mentele, R.
Sampaio, M.
Sampaio, CAM
Oliva, MLV
Institución
Resumen
A novel serine proteinase inhibitor, DgTI, was purified from Dioclea glabra seeds by acetone precipitation, and ion-exchange and reverse phase chromatography. the inhibitor belongs to the Bowman-Birk family, and its primary sequence, determined by Edman degradation and mass spectrometry, of 67 amino acids is: SSGPCCDRCRCTKSEPPQCQCQDVRLNSC-HSACEACVCSHSMPGLCSCLDITHFCHEPCKSSGD- DED, Although two reactive sites were determined by susceptibility to trypsin (Lys(13) and His(40)), the inhibitory function was assigned only to the first site. the inhibitor forms a 1:1 complex with trypsin, and Ki is 0.5 x 10(-9) M. Elastase, chymotrypsin, kallikreins, factor Xa, thrombin, and plasmin were not inhibited. By its properties, DgTI is a Bowman-Birk inhibitor with structural and inhibitory properties between the class of Bowman-Birk type I (with a fully active second reactive site), and Bowman-Birk type II (devoid of second reactive site). (C) 1999 Academic Press.