WATER INSOLUBLE DERIVATIVES OF PROTEINS WITH BIOLOGICAL ACTIVITY.
Final rept. 1 Jul 67-30 Jun 68,
WEIZMANN INST OF SCIENCE REHOVOTH (ISRAEL) DEPT OF BIOPHYSICS
Pagination or Media Count:
A series of compounds were prepared and their properties as substrates of Chymotrypsin were investigated. A comparison of values of kinetic parameters for the various series, led to an estimate of the effect of side-chain length n of the polyfunctional ester substrates series a, on the individual rate constants of the chymotrypsin catalyzed hydrolysis of these compounds. A systematic study of the kinetic behavior of chymotrypsin, polyglutamyl chymotypsin PGCH and polyornithyl-polyornithylochymotrypsin POOCH using acetyl-L-tyrosine ethyl ester as substrate were carried out. The values of kcat for POOCH were lower and for PGCH higher as compared to the kcat calues of native chymotrypsin. The values of KMapp for POOCH were higher by about one order of magnitude as compared to the native enzyme. The values of KMapp for PGCH were similar to KMapp of chymtypsin. The kinetic data was interpreted in terms of specific nearest neighbor effects of the charged side-chains on the groups involved in the deacylation step, and perturbation of the binding constant, Ks, in the case of POOCH. Author