OSTRICH (STRUTHIO-CAMELUS) CARBOXYPEPTIDASE-A - PURIFICATION, KINETIC-PROPERTIES AND CHARACTERIZATION OF THE PANCREATIC-ENZYME

1. Carboxypeptidase A(beta) and carboxypeptidase A(tau)-type from the pancreas of the ostrich were purified by water extraction of acetone powder, aminobenzylsuccinic acid affinity and hydroxylapatite chromatography. 2. The final preparations were homogeneous when subjected to SDS-PAGE and PAGE. The M(r) values obtained from SDS-PAGE for CPA(beta) and CPA(tau)-type were 34,600 and 34,400, respectively. 3. The effects of inhibitors (1,10 phenanthroline and indole-3-acetic acid), pH and temperature on CPA activity were examined. K-i-values for CPI, PPA, D-phe, D-trp and aminobenzylsuccinic acid were determined. 4. K-m, k(cat) and k(cat)/K-m values were determined for hipp-phe, cbz-gly-phe, cbz-(gly)(2)-phe, cbz-gly-leu, cbz-(gly)(2)-leu and cbz-(gly)(2)-val. 5. N-terminal sequencing and amino acid analysis were performed for CPA(beta) and CPA(tau)-type.