Isolation and preliminary characterization of a 22-kDa protein with trypsin inhibitory activity from toad Bufo andrewsi skin.
A novel trypsin inhibitor termed BATI was purified to homogeneity from the skin extracts of toad Bufo andrewsi by successive ion-exchange, gel-filtration and reverse-phase chromatography. BATI is basic single chain glycoprotein, with apparent molecular weight of 22 kDa in SDS-PAGE. BATI is a thermal stable competitive inhibitor and effectively inhibits trypsin's catalytic activity on peptide substrate with the inhibitor constant (K(i)) value of 14 nM and shows no inhibitory effect on chymotrypsin, thrombin and elastase. The N-terminal sequence of BATI is EKDSITD, which shows no similarity with other known trypsin inhibitors.
Zhao
Yu
Y
Department of Animal Toxinology, Kunming Institute of Zoology, The Chinese Academy of Sciences, 32 East Jiao Chang Road, Kunming, Yunnan 650223, People's Republic of China.
Jin
Yang
Y
Lee
Wen-Hui
WH
Zhang
Yun
Y
D000818:Animals; D002025:Bufonidae; D002384:Catalysis; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D008970:Molecular Weight; D011485:Protein Binding; D012867:Skin / Q000737:chemistry*; D014361:Trypsin Inhibitors / Q000737:chemistry / Q000302:isolation & purification*
D014361:Trypsin Inhibitors