The participation of an enzyme-bound oxygen group in a coenzyme A transferase reaction.
نویسندگان
چکیده
A well supported mechanism for succinyl-CoA:3-ketoacid coenzyme A transferase (EC 2.8.3.5) involving an enzymeCoA intermediate requires the participation of an oxygen atom of the enzyme or of the CoA moiety. Measurements of loss of 180 from acetoacetate show that CoA oxygens do not participate. An oxygen-containing group on the enzyme is reversibly labeled from succinateJ*O in the presence of acetoacetyl-Cob or succinyl-CoA. The IsO-labeled enzyme does not contain succinyl or CoA moieties. A binding of acetoacetate-14C to the enzyme preparation does not appear to reflect an anhydride precursor to the enzyme-CoA form.
منابع مشابه
The Journal of Biological Chemistry
A well supported mechanism for succinyl-CoA:3-ketoacid coenzyme A transferase (EC 2.8.3.5) involving an enzymeCoA intermediate requires the participation of an oxygen atom of the enzyme or of the CoA moiety. Measurements of loss of 180 from acetoacetate show that CoA oxygens do not participate. An oxygen-containing group on the enzyme is reversibly labeled from succinateJ*O in the presence of a...
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 244 9 شماره
صفحات -
تاریخ انتشار 1969