Ostrich pancreatic secretory trypsin inhibitor was isolated and purified using acid extraction, salt fractionation, SP-Sephadex C-50 and QAE-Sephadex A-25 chromatography and RP-HPLC. The amino acid sequence of ostrich PSTI showed it is a single peptide chain containing 69 amino acid residues with the highest homology between ostrich and chicken PSTI. The molecular weight, as determined by electronspray mass spectrometry and from amino acid sequence data, is 7650 Da. The isoelectric point of ostrich PSTI was found to be 5.7. Ostrich PSTI specifically inhibited ostrich and commercial bovine trypsin with K(i) values of 8.0 x 10-9 and 2.4 x 10-7 M, respectively, while no inhibitory effects were observed with other serine proteases.
|Number of pages||8|
|Journal||International Journal of Peptide and Protein Research|
|Publication status||Published - 1996|
- Amino acid sequence
- Kazal inhibitor
- Pancreatitic secretory trypsin inhibitor
ASJC Scopus subject areas