Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.21.1 (
chymotrypsin
)
10,938
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The metal content of carboxypeptidase Y was analyzed by the atomic absorption method. After exhaustive dialysis against an EDTA solution, the enzyme showed no loss of activity nor any significant content of metals (Zh,Mg,Ca,Cu,Mn,Ni,Fe, and Co). The activity was, however, rather sensitive to preincubation with various metals. The reactivity of a serine residue of the enzyme was also reevaluated.
Diisopropyl fluorophosphate
(
DFP
) and phenylmethanesulfonyl fluoride (PMSF) stoichiometrically and irreversively inhibited the enzyme. The rate of inactivation with
DFP
was much faster than that for typsin [EC 3.4.21.4] and
chymotrypsin
[
EC 3.4.21.1
.], while the rate with PMSF was one-fifteenth of that for
chymotrypsin
. The pH-dependence of the inactivation by
DFP
was similar to that of the enzymatic hydrolysis of acetylphenylalanine ethyl ester. The present results indicate that carboxypeptidase Y is free of metals and has a serine residue with a vital role in the catalytic process, though the functional role of this SH group remains to be clarified.
...
PMID:Further confirmation of carboxypeptidase Y as a metal-free enzyme having a reactive serine residue. 0 4
