Aldehyde dehydrogenase catalyses acetaldehyde formation from 4-nitrophenyl acetate and NADH.
نویسندگان
چکیده
Incubation of sheep liver cytoplasmic aldehyde dehydrogenase with the substrate 4-nitrophenyl [14C]acetate in the presence of NADH leads to the formation of 14C-labelled acetaldehyde. This observation strongly supports the idea that the esterase and dehydrogenase activities of the enzyme occur at the same site and involve the intermediacy of a common acyl-enzyme.
منابع مشابه
The action of cytoplasmic aldehyde dehydrogenase on methyl p-nitrophenyl carbonate and p-nitrophenyl dimethylcarbamate.
Cytoplasmic aldehyde dehydrogenase catalyses the hydrolysis of methyl p-nitrophenyl (PNP) carbonate at an appreciable rate that is markedly stimualted by NAD+ or NADH. The nuleotides accelerate the rate-limiting hydrolysis of the acyl-enzyme intermediate while slowing the observed burst of p-nitrophenoxide production. With PNP dimethylcarbamate the enzyme catalyses the slow release of approx. 1...
متن کاملFurther studies of the action of disulfiram and 2,2'-dithiodipyridine on the dehydrogenase and esterase activities of sheep liver cytoplasmic aldehyde dehydrogenase.
1. Pre-modification of cytoplasmic aldehyde dehydrogenase by disulfiram results in the same extent of inactivation when the enzyme is subsequently assayed as a dehydrogenase or as an esterase. 2. 4-Nitrophenyl acetate protects the enzyme against inactivation by disulfiram, particularly well in the absence of NAD+. Some protection is also provided by chloral hydrate and indol-3-ylacetaldehyde (i...
متن کاملStudies of the esterase activity of cytosolic aldehyde dehydrogenase with resorufin acetate as substrate.
Resorufin acetate is a very good substrate for sheep liver cytosolic aldehyde dehydrogenase, both from the point of view of practical spectrophotometry and in terms of information provided about the nature of the catalysis shown by this enzyme. p-Nitrophenyl (PNP) acetate competes against resorufin acetate for the enzyme's active site (although relatively weakly as the latter substrate has the ...
متن کاملHuman Liver Aldehyde Dehydrogenase
Human liver aldehyde dehydrogenase has been found to be capable of hydrolyzing p-nitrophenyl esters. Esterase and dehydrogenase activities exhibited identical ion exchange and affinity properties, indicating that the same protein catalyzes both reactions. Competitive inhibition of esterase activity by glyceraldehyde and chloral hydrate furnished evidence that p-nitrophenyl acetate was hydrolyze...
متن کاملHigh concentrations of aldehydes slow the reaction of cytoplasmic aldehyde dehydrogenase with thiol-group modifiers.
High concentrations of aldehydes slow the inactivation of cytoplasmic aldehyde dehydrogenase by disulfiram and also slow the reaction of the enzyme with 2,2'-dithiodipyridine. It is concluded that a low-affinity aldehyde-binding site is probably the site at which thiol-group modifiers react with aldehyde dehydrogenase, as well as being the active site for hydrolysis of 4-nitrophenyl acetate.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Biochemical journal
دوره 238 2 شماره
صفحات -
تاریخ انتشار 1986