Xanthine oxidase inactivation by reagents that modify thiol groups
نویسندگان
چکیده
منابع مشابه
Non-thiol reagents regulate ryanodine receptor function by redox interactions that modify reactive thiols.
The Ca(2+) release channel (CRC) from sarcoplasmic reticulum (SR) is rich in thiol groups, and their oxidation/- reduction by thiol reagents activates/inhibits the CRC. Most channel regulators are not thiol reagents, and the mechanism of their action is illusive. Here the authors show that many channel activators act as electron acceptors, while many channel inhibitors act as electron donors in...
متن کاملXanthine Oxidase. Vii. Inhibition by Amino Group Reagents.
In the previous paper (1) milk xanthine oxidase was reported to oxidize quaternary, heterocyclie compounds only at pH values above 9.6, whereas purines and aldehydes are most rapidly oxidized at neutral pH. This specificity change was attributed to an alteration in the substrate-binding site brought about by the titration of a group or groups with a pK, value of about 10.7. This suggestion prom...
متن کاملReversible Inactivation of Cytochrome Oxidase by Disulfide Bond Reagents.
Recent studies on the chemical nature of cytochrome oxidase (cytochrome c :02 oxidoreductase, EC 1.9.3.1) have been concerned largely with the structure of its iron-porphyrin prosthetic group (cj. (l)), the importance of copper as an integral component of the enzyme (e.g. (2-5)), and the possible role of a lipid factor (e.g. (6-8)). By contrast, little work has been done on the nature of the fu...
متن کاملPartial inactivation of cytochrome c oxidase by nonpolar mercurial reagents.
Purified beef heart cytochrome c oxidase is inactivated to the extent of 35 to 50% by the nonpolar mercurial reagents mercuric chloride and ethylmercuric chloride. The inactivation is complete within 5 min. In titrations of activity, the plateau level of inactivation is attained at added ethylmercuric chloride:heme a ratios of about 1:1. Up to 3 mercury atoms/heme a are bound to the oxidase, al...
متن کاملCholine acetyltransferase. Inhibition by thiol reagents.
Choline acetyltransferase (EC 2.3.1.6) catalyzes the reversible transfer of the acetyl group from acetyl coenzyme A to choline. Previous studies are consistent with the idea that an active site sulfhydryl group reacts with acetyl coenzyme A to form an acetyl-thioenzyme intermediate and coenzyme A (ROSKOSKI, R., JR. (1973) Biochemistry 12, 3709). Choline then reacts with the acetyl-enzyme to for...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Biochemical Journal
سال: 1967
ISSN: 0306-3283
DOI: 10.1042/bj1050585