ISSN:
1573-4943
Keywords:
Papain
;
photoreversible inhibitor
;
light-sensitive protecting group
;
1-(4,5-dimethoxy-2-nitrophenyl)-2-nitroethene
;
1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract 1-(4,5-Dimethoxy-2-nitrophenyl)-2-nitroethene (1) was shown to be an irreversible inhibitor of papain (EC 3.4.22.2), causing a complete inhibition (120 min preincubation, pH 8.0), assuming that it attached to Cys-25 at the active site of the enzyme (while a short preincubation time caused activation). Only partial inhibition of papain was achieved, however, with 1,1-dicyano-2-(4,5-dimethoxy-2-nitrophenyl)-ethene (2), a compound synthesized in this work, which is also an irreversible inhibitor of papain. Since both compounds 1 and 2, and in each case of the inhibited enzyme, were 2-nitrobenzyl derivatives, they and the modified enzyme were expected to be photosensitive. Indeed, irradiation of the inhibited enzyme in the presence of mercaptoethanol resulted in a full recovery of the enzyme activity following inactivation with compound 1 (similar to our previous finding with β-galactosidase) and up to 67% recovery following inhibition with compound 2.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007030532433
Permalink