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Hepatic Phenylalanine Hydroxylase and PKU
1975The conversion of phenylalanine to tyrosine in mammalian tissues is catalyzed by a complex enzyme system composed of several essential enzymes and cofactors. All of these components have been assayed in liver biopsy samples from patients with the classic form of PKU.
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A simple radioisotope assay for phenylalanine hydroxylase
Analytical Biochemistry, 1967Abstract An isotopic assay for phenylalanine hydroxylase activity has been devised. The assay involves incubation of the enzyme with p -tritio- l -phenylalanine followed by the addition of N -iodosuccinimide to iodinate the tyrosine produced. The tritium released by this combination appears as tritiated water and is proportional to the amount of ...
G, Guroff, A, Abramowitz
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A specific kinetic assay for phenylalanine hydroxylase
Analytical Biochemistry, 1973Abstract An assay procedure is given which is speedy, accurate, and specific, permitting direct recording of velocities, and obviating the use of reagents other than those necessary for the enzymatic reaction itself. The method is suitable for the study of enzyme mechanism and inhibition and also offers distinct advantages when used for other ...
J, Ayling +3 more
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The mechanism of phenylalanine hydroxylase.
Federation proceedings, 1982The site of oxygen binding during phenylalanine hydroxylase (PAH)-catalyzed turnover of phenylalanine to tyrosine has been tentatively identified as the 4a position of the tetrahydropterin cofactor, based on the spectral characteristics of an intermediate generated from both 6-methyltetrahydropterin and tetrahydrobiopterin during turnover. The rates of
R A, Lazarus +6 more
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Regulation of the activity of hepatic phenylalanine hydroxylase
Advances in Enzyme Regulation, 1986Rat liver phenylalanine hydroxylase catalyzes the tetrahydropterin-dependent oxidation of phenylalanine to tyrosine, according to equation 1. In addition to the naturally-occurring coenzyme, tetrahydrobiopterin (BH4), certain synthetic analogs of BH4 such as 6-methyltetrahydropterin (6MPH4) have high cofactor activity.
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A direct assay for liver phenylalanine hydroxylase
Biochimica et Biophysica Acta (BBA) - Enzymology, 1969Abstract 1. 1 An assay for liver phenylalanine hydroxylase ( l -phenylalanine, tetrahydropteridine: O2 oxidoreductase (4-hydroxylating), EC 1.14.3.1) based on the nonenzymatic regeneration of 2-amino-4-hydroxy-6,7-dimethyltetrahydropteridine from 2-amino-4-hydroxy-6,7-dimethyldihydropteridine (quinonoid form) by dithiothreitol is described ...
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Effects of phenylalanine on phenylalanine hydroxylase separation and stability
Biochemical Medicine, 1985R D, Crawford, E C, Layne, S P, Bessman
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On the mechanism of action of phenylalanine hydroxylase
Biochemical Society Transactions, 1985S, Benkovic +6 more
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The Mechanism of Action of Phenylalanine Hydroxylase
Annals of the New York Academy of Sciences, 1986S J, Benkovic +5 more
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