This study reports the isolation and partial characterisation of the ostrich serpin, α2AP, and its target enzyme, ostrich plasmin, in its active and inactive proenzyme, namely plasminogen, forms. Ostrich α2AP was purified using L-lysine-Sepharose chromatography, ammonium sulfate fractionation, and SuperQ-650S and ostrich LBSI-Sepharose chromatographies. It revealed a Mr of 84 K (thousand) and had one and two N-terminal amino acids in common with 11 of those of human and bovine α2AP, respectively. It showed the largest inhibitory effect on ostrich plasmin, followed by bovine trypsin and plasmin, respectively, and much less plasmin inhibition than bovine aprotinin, but much more so than human α2AP, DFP and EACA. Ostrich plasminogen was highly purified after L-lysine-Sepharose chromatography and showed a Mr of 92 K, a total of 775 amino acids and its N-terminal sequence showed ∼53% identity with those of human, rabbit, cat, and ox plasminogens. Ostrich plasmin, obtained by the urokinase-activation of ostrich plasminogen, revealed a Mr of 78 K, a total of 638 amino acids, an N-terminal sequence showing two to four residues identical to five of those of human, cat, dog, rabbit, and ox plasmins, and pH and temperature optima of 8.0 and 40°C, respectively.
|Number of pages||12|
|Journal||Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology|
|Publication status||Published - 2001 Jan 1|
ASJC Scopus subject areas
- Molecular Biology