Mechanism of Rhodanese Action: Isotopic Tracer Studies
نویسندگان
چکیده
منابع مشابه
Mechanism of rhodanese action: isotopic tracer studies.
In a previous publication (2) a double displacement mechanism for the catalytic activity of rhodanese (thiosulfate cyanide sulfurtransferase) was proposed on the basis of polarographic evidence. In addition it was concluded from the polarographic data that crystahine beef liver rhodanese is an enzyme-substrate intermediate containing two activated substrate sulfur atoms per molecule. This commu...
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Fructose consumption and its implications on public health are currently under study. This work reviewed the metabolic fate of dietary fructose based on isotope tracer studies in humans. The mean oxidation rate of dietary fructose was 45.0% ± 10.7 (mean ± SD) in non-exercising subjects within 3-6 hours and 45.8% ± 7.3 in exercising subjects within 2-3 hours. When fructose was ingested together ...
متن کاملStudies on the active site of rhodanese.
The complete loss of enzymic activity on reaction with alkylating agents, aromatic nitro compounds, or aliphatic mercaptans indicates the importance of sulfhydryl groups for catalysis. Analyses during the course of inactivation with any of these reagents revealed the loss of one of the two -SH groups in the rhodanese monomer when inactivation was complete. Amino acid analysis of iodoacetate-ina...
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The kinetic behavior of rhodanese (thiosulfate: cyanide sulfurtransferase, EC 2.8.1.1) was investigated at pH values from 5.0 to 10.8. The binding of thiosulfate was shown to be dependent upon a pK’ of 9.9, with the protonated enzyme binding the substrate much more strongly than the deprotonated form. An enzymic nucleophile displaces sulfite to form the sulfur-substituted enzyme. This reaction ...
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ژورنال
عنوان ژورنال: Journal of Biological Chemistry
سال: 1962
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(18)93959-1