Results 121 to 130 of about 1,181 (159)
Some of the next articles are maybe not open access.
New Pathway of Conversion of Pyridoxal to 4-Pyridoxic Acid
Enzyme, 2017The only enzyme demonstrated so far to catalyze the formation of 4-pyridoxic acid, the final excretory product of vitamin B(6), was aldehyde oxidase. In this paper we have presented an evidence that another enzyme, NAD^+-dependent aldehyde dehydrogenase, is capable of catalyzing this reaction. Rat mutants with high, low and no aldehyde oxidase activity
M, Stanulović +3 more
openaire +2 more sources
Neurochemical Research, 1985
Previous studies from this laboratory have shown that pyridoxal-5'-sulphate, the synthetic analogue of pyridoxal phosphate, causes epileptic seizures including tonic-clonic convulsions. These seizure activities are prevented or reversed by GABA or muscimol.
M, Ebadi, A, Earle, S, Wilt
openaire +2 more sources
Previous studies from this laboratory have shown that pyridoxal-5'-sulphate, the synthetic analogue of pyridoxal phosphate, causes epileptic seizures including tonic-clonic convulsions. These seizure activities are prevented or reversed by GABA or muscimol.
M, Ebadi, A, Earle, S, Wilt
openaire +2 more sources
A synthesis of the lactone of 5‐pyridoxic acid
Recueil des Travaux Chimiques des Pays-Bas, 1959AbstractThe reduction of dimethyl 2‐methyl‐3‐hydroxypyridine 4,5‐dicarboxylate (I) with sodium borohydride and aluminium chloride gives no pyridoxol but a precursor i.e. the lactone II, corresponding to 5‐pyridoxic acid. No isomeric lactone (III) corresponding to 4‐pyridoxic acid was isolated.
H. M. Wuest +4 more
openaire +1 more source
The American Journal of Clinical Nutrition, 1986
A high-performance liquid chromatography method for quantitation of urinary 4-pyridoxic acid excretion is presented. Urine samples were treated with HCl to form 4-pyridoxic acid lactone. Acid-treated urine samples were diluted and analyzed by cation-exchange chromatography involving post-column alkalinization and fluorescence detection.
J B, Ubbink +3 more
openaire +2 more sources
A high-performance liquid chromatography method for quantitation of urinary 4-pyridoxic acid excretion is presented. Urine samples were treated with HCl to form 4-pyridoxic acid lactone. Acid-treated urine samples were diluted and analyzed by cation-exchange chromatography involving post-column alkalinization and fluorescence detection.
J B, Ubbink +3 more
openaire +2 more sources
Russian Journal of General Chemistry, 2008
The mechanism of chemical transformations of pyridoxal and pyridoxal 5′-phosphate condensation products with amino acids is studied by kinetic measurements. The Schiff bases are shown to be fairly stable in neutral media. In acid media, the Schiff bases are hydrolyzed into the initial components. In alkaline media, cleavage of α-hydrogen from the amino
F. V. Pishchugin, I. T. Tuleberdiev
openaire +1 more source
The mechanism of chemical transformations of pyridoxal and pyridoxal 5′-phosphate condensation products with amino acids is studied by kinetic measurements. The Schiff bases are shown to be fairly stable in neutral media. In acid media, the Schiff bases are hydrolyzed into the initial components. In alkaline media, cleavage of α-hydrogen from the amino
F. V. Pishchugin, I. T. Tuleberdiev
openaire +1 more source
Interaction of pyridoxal-5′-phosphate and acetohydroxy acid isomeroreductase
Biochemical and Biophysical Research Communications, 1971Summary Acetohydroxy acid isomeroreductase is irreversibly inactivated upon binding approximately 8 moles of pyridoxal-5′-phosphate (PLP) followed by reduction with NaBH4. Various analogs of PLP cause little or no inactivation. Inactivation is both more rapid and occurs at lower PLP concentrations in the presence of the specific cofactor NADPH, but ...
E M, Shematek, S M, Arfin
openaire +2 more sources
Assay of pyridoxal-5'-phosphate, pyridoxal and pyridoxic acid in biological material.
International journal for vitamin and nutrition research. Internationale Zeitschrift fur Vitamin- und Ernahrungsforschung. Journal international de vitaminologie et de nutrition, 1990The two vitamin B6-vitamers having an aldehyde function are oxidised to the corresponding acids and subjected to an HPLC separation on an RP 18 phase with a solvent consisting of 5% methanol in phosphate buffer at pH 3.5. The detection is carried out by fluorometry with excitation at 318 nm and emission at 418 nm.
D, Hess, J P, Vuilleumier
openaire +1 more source
Stereochemistry of pyridoxalamino acid model systems
Inorganica Chimica Acta, 1983Abstract Pyridoxal phosphate is the essential cofactor for most of the enzymic reactions undergone by amino acids during metabolism [1]. All these reactions proceed through the formation of a Schiff base, such as I, followed by cleavage of one of the bonds to the amino acid α-carbon atom.
Luigi Casella, Michelle Gullotti
openaire +1 more source
Stereochemistry of condensation and transaldimination of amino acids by pyridoxal
Russian Journal of General Chemistry, 2013The stereochemistry of the products of condensation and transaldimination of L-α- and D-α- alanines with pyridoxal has been studied. Structure of intermediate amino alcohols, aminals, and of the final Schiff’s bases depends on their fragments location with respect to the pyridine ring plane.
F. V. Pishchugin, I. T. Tuleberdiev
openaire +1 more source