The effect of <scp>l</scp>-ascorbate on catecholamine biosynthesis (<i>Short Communication</i>)
Biochemical JournalPublished 1 March 1973Open access
K. J. Stone, B. H. Townsley
Citations32
SJR quartileQ1
SJR score2.06
SNIP0.98
Generate an AI Snapshot to get a quick, structured summary of this paper.
Study Snapshot
ObjectiveStudy objective
MethodsResearch methodology
PopulationPopulation studied
Sample sizeSample sizes
OutcomesStudy outcomes here
ResultsStudy results comes here
LimitationsResearch study limitations comes here
A concise AI-generated summary of the paper will appear here once you click Generate AI Snapshot.
TL;DR
L-Ascorbate stimulates the enzymic hydroxylation of phenylalanine in vitro by recycling tetrahydrobiopterin, which reduces O(2) utilized in the reaction.
Abstract
l-Ascorbate stimulates the enzymic hydroxylation of phenylalanine in vitro by recycling tetrahydrobiopterin, which reduces O(2) utilized in the reaction. It is suggested that ascorbate might have a similar function in vivo; this would explain the apparent regulation of tyrosine hydroxylase and tryptophan hydroxylase activities by this vitamin.
Keywords
Agricultural and Biological SciencesMedicine
Journal of Biological ChemistryPROTEIN MEASUREMENT WITH THE FOLIN PHENOL REAGENT
318,326 Citations1951OliverH. Lowry, NiraJ. Rosebrough +2 more
Procedures are described for measuring protein in solution or after precipitation with acids or other agents, and for the determination of as little as 0.2 gamma of protein.
Journal of Biological ChemistryTHE CHEMICAL ESTIMATION OF TYROSINE AND TYRAMINE
319 Citations1952Sidney Udenfriend, Jack R. Cooper
1-Nitroso-2-naphthol reacts with both tyrosine and tyramine to form a red-colored product which gradually changes to a stable yellow chromo- phore and has been isolated.
Journal of Biological ChemistryPurification and Some Physical Properties of Phenylalanine Hydroxylase from Rat Liver
160 Citations1970Seymour Kaufman, Daniel B. Fisher
Phenylalanine hydroxylase has been obtained from rat liver in a form that is 85 to 95% pure, and the dimers of each isozyme will dissociate to the monomeric forms by dilution of the enzyme or by increasing the temperature from 0 to 30°.
Journal of Biological ChemistryA Protein That Stimulates Rat Liver Phenylalanine Hydroxylase
117 Citations1970Seymour Kaufman
Kinetic data suggest that the stimulating protein in partially purified preparations of sepiapterin reductase influences a reversible association-dissociation of the hydroxylase.
Journal of Cellular PhysiologyPhenylalanine hydroxylase activity in mammalian cells
102 Citations1969Ara Tourian, Judy M. Goddard +1 more
Survey of twelve mouse tissues revealed the presence of appreciable phenylalanine hydroxylase activity in the pancreas and kidney as well as the liver but in no other of the tissues tested, and single cell suspensions of mouse liver were prepared by use of tetraphenylboron.
European Journal of BiochemistryRat Liver Phenylalanine Hydroxylase
77 Citations1969Klaus H. Nielsen
The activity of rat liver phenylalanine hydroxylase has been measured in systems which, in addition to the components necessary forhydroxylation, contained ascorbic acid and catalase and certain non-reducing inhibitors can also stabilize the enzyme.
Biochimica et Biophysica Acta (BBA) - EnzymologyA direct assay for liver phenylalanine hydroxylase
71 Citations1969Clark Bublitz
Dithiothreitol not only regenerates the tetrahydropteridine from dihydroptersidine but it also effectively destroys peroxide formed during the aerobic oxidation of the tetRahydrop teridine.
Analytical BiochemistryA simple radioisotope assay for phenylalanine hydroxylase cofactor
63 Citations1967Gordon Guroff, Carol A. Rhoads +1 more
Recovery studies indicate that the naturally occurring cofactor, tetrahydrobiopterin, can be accurately measured by this method and the advantages of the Pseudomonas phenylalanine hydroxylase for these measurements are presented.
Biochimica et Biophysica Acta (BBA) - General SubjectsPhenylalanine-hydroxylating system in the human fetus at different developmental ages
38 Citations1971Alexander Jakubovič
It is demonstrated that both phenylalanine hydroxylase and dihydropteridine reductase as well as the natural cofactor are present in the liver at an early stage of fetal development.
Biochemical and Biophysical Research CommunicationsConversion of tryptophan to 5-hydroxytryptophan by phenylalanine hydroxylase
34 Citations1961J Renson, Frederick K. Goodwin +2 more
THE JOURNAL OF VITAMINOLOGYEffect of Ascorbic Acid on Hydroxylase Activity
32 Citations1970Yoko Nakashima, Ryokuero Suzue +2 more
The results indicated that the activities of tyrosine hydroxyl enzyme and tryptophan-5-hydroxylase of the adrenal gland, liver and brain of the nonscorbutic guinea pig were higher than the values found in the scorbutic Guinea pig, although no significant change in the activity of dehydrogenase was observed in the tissues of the non-scorbutic and scorbuti guinea pigs.
Biochimica et Biophysica Acta (BBA) - EnzymologyPhenylalanine hydroxylase of Macaca irus. Purification of two components of the enzyme
14 Citations1971Richard G.H. Cotton
Phenylalanine hydroxylase has been purified up to 424-fold from the liver of the Cynomolgus monkey after stabilization of the enzyme during extraction and chromatography.
MetabolismDefect in synthesis of epinephrine in premature infants with tyrosinemia
4 Citations1971Irwin J. Light, James M. Sutherland +2 more
The relationship between elevated serum tyrosine levels and urinary catecholamine excretion was studied in premature infants and in one patient with tyrosinosis, suggesting that the decreased excretion of epinephrine in the premature infants with elevated serum Tyrosine is not a result of the increased serum tyosine level.
