Results 221 to 230 of about 6,229 (253)

Interaction of pyridoxal-5′-phosphate and acetohydroxy acid isomeroreductase

Biochemical and Biophysical Research Communications, 1971
Summary 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 ...
Stuart M. Arfin, Eleanor M. Shematek
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Kinetics and Mechanism of the Condensation of Pyridoxal with Amino Acids

Russian Journal of General Chemistry, 2005
The kinetics and mechanism of the condensation of amino acids with pyridoxal were studied in relation to the amino acid structure, solvent, pH, and temperature. A spectrophotometric study revealed several kinetically discernible reaction steps. The condensation rate as a function of pH passes through a maximum, which is caused by formation of two ...
F. V. Pishchugin, I. T. Tuleberdiev
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Stereochemistry of condensation and transaldimination of amino acids by pyridoxal

Russian Journal of General Chemistry, 2013
The 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
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Pyridoxal enzymes acting on D-amino acids

Pure and Applied Chemistry, 1994
Abstract
Nobuyoshi Esaki, Kenji Soda
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A simple, sensitive and reproducible assay for pyridoxal 5′-phosphate and 4-pyridoxic acid in human plasma

Clinica Chimica Acta, 1999
We describe a procedure for the measurement of pyridoxal 5'-phosphate and of 4-pyridoxic acid in human plasma samples. It is based on the conversion of pyridoxal 5'-phosphate to 4-pyridoxic acid 5'-phosphate by cyanide in alkaline medium, followed by a high pressure liquid chromatographic separation, with fluorescence detection at acid pH. The assay is
Christopher J. Bates, Kristina Pentieva, Andrew Macdonald, Neal Matthews   +3 more
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Pyridoxal phosphate. 5. 2-Formylethynylphosphonic acid and 2-formylethylphosphonic acid, potent inhibitors of pyridoxal phosphate binding and probes of enzyme topography

Journal of Medicinal Chemistry, 1976
AbstractAus Propargylaldehydacetal (Ia) erhält man über die Lithio= Verbindung (Ib) mit Diäthylphosphoresterchlorid den Phosphonester (II), der auch über das Bromid (Ic) mit dem entsprechenden Diesterphosphat in allerdings geringerer Ausbeute erhalten wird.
A. J. Rudinskas, T. L. Hullar
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Enantiomer Synthesis of Amino Acids with Pyridoxal Enzymes

1987
We here describe recent developments in the enzymatic synthesis of various optically active amino acids with pyridoxal enzymes including L-methionine γ-lyase, 0-acety1-homoserine (thiol)-lyase, D-amino acid aminotransferase, D-cysteine desulfhydrase, cystathionine γ-lyase, tryptophan synthase and amino acid racemases.
H. Tanaka, Kenji Soda, Nobuyoshi Esaki, Katsuyuki Tanizawa   +3 more
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ChemInform Abstract: CATALYTIC ACTIVITIES OF PYRIDOXAL ANALOGUES PART 1, THE CATALYTIC EFFECTS OF PYRIDOXAL, PYRIDOXAL METHOCHLORIDE, AND PYRIDOXAL N‐OXIDE ON THE RACEMIZATION OF L‐GLUTAMIC ACID

Chemischer Informationsdienst, 1975
AbstractIn einer verbesserten Synthese werden ausgehend von Pyridoxal ‐ HCl (I) a) über die Stufen (II) und (III), das Methochlorid (IV) bzw. b) über die Stufen (II) und (V) das N‐Oxid (VI) dargestellt.
Sakae Emoto, Makoto Ando
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A direct method for preparing pyridoxal and 4‐pyridoxic acid [PDF]

Journal of Heterocyclic Chemistry, 1967
H. Ahrens, W. Korytnyk
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A qualitative and quantitative color reaction for pyridoxal with sulfuric acid

Analytica Chimica Acta, 1959
The carbonyl-phenol-acid reaction system yields color reactions with phenols, carbonyl compounds (aldehydes and ketones), and inorganic acids. 'I'o test for one of the components of this reaction system, the remaining two components constitute the specific reagents.
Robert N. Sass, Victor E. Levine
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