Loading…
Protein Conjugates with Water-Soluble Poly(alkylene oxide)s Entrapped in Hydrated Reversed Micelles
Conjugates of α-chymotrypsin (ChT) with poly(ethylene glycol) (PEG) and block copolymers of ethylene and propylene oxides (proxanols) have been synthesized. The molecular mass of the polymers used was 2 kDa. The conjugates contained five to seven polymer chains per enzyme molecule. Hydrolysis of N-t...
Saved in:
Published in: | Bioconjugate chemistry 1997-09, Vol.8 (5), p.637-642 |
---|---|
Main Authors: | , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Conjugates of α-chymotrypsin (ChT) with poly(ethylene glycol) (PEG) and block copolymers of ethylene and propylene oxides (proxanols) have been synthesized. The molecular mass of the polymers used was 2 kDa. The conjugates contained five to seven polymer chains per enzyme molecule. Hydrolysis of N-trans-cinnamoylimidazole catalyzed by the conjugates of ChT with poly(alkylene oxide)s was studied in 0.05 M Tris-HCl buffer at pH 8.0 and in the system of the hydrated reversed micelles of aerosol OT (AOT) in octane at 25 °C. The deacylation rate constant k 3 for the conjugates in buffer solution was 1.5−1.8-fold higher than that for native ChT. The value of the [H2O]:[AOT] ratio corresponding to the maximum on k 3 versus [H2O]:[AOT] curves for the conjugates (ca. 16) allows the dimensions of their molecules to be evaluated. The radius of the conjugate molecules was found to be about 2.8 nm. The value of k 3 for the conjugate of ChT with PEG, as in the case of native ChT, remains constant when the concentration of AOT is varied. However, the deacylation rate constant for the conjugates of ChT with proxanols decreases with the increase in AOT concentration, which indicates that these conjugates are able to interact with the micellar matrix and therefore may be considered membranotropic compounds. |
---|---|
ISSN: | 1043-1802 1520-4812 |
DOI: | 10.1021/bc970041t |