Extracts of rabbit liver and brain are known (1, 2) to oxidize pyridoxine 5-phosphate to pyridoxal 5-phosphate much faster than they oxidize free pyridoxine to pyridoxal. Comparison of the two activities during limited purification indicated that different enzymes catalyzed the two reactions (1). Pogell (3) had shown previously that oxidation of pyridoxamine 5-phosphate was catalyzed by an enzy...

OBJECTIVE Intractable epilepsy is a serious neurologic problem with different etiologies. Decreased levels of pyridoxal phosphate in cerebral spinal fluid of patients with intractable epilepsy due to pyridoxine dependency epilepsy are reported. The aim of this study was to compare plasma pyridoxal 5´-phosphate level in patients with intractable and controlled epilepsy. MATERIALS & METHODS Thi...

Tritium-labeled pyridoxamine, pyridoxal S/-phosphate, and pyridoxine 5’-phosphate were prepared and administered intravenously to mice, and the distribution of isotope in liver and carcass between pyridoxine, pyridoxine 5’-phosphate, pyridoxal, pyridoxal S/-phosphate, pyridoxamine, and pyridoxamine 5’-phosphate was determined at different times after administration. The vitamin B6 forms were ex...

of pyridoxal 5 -phosphate. Biochim Biophys Acta 1973;304:765–73. 13. Dalton K, Dalton MT. Characteristics of pyridoxine overdose neuropathy syndromes. Acta Neurol Scand 1987;76:8–11. 14. Ubbink JB, Serfontein WJ, De Villiers LS. Stability of pyridoxal 5 -phosphate semicarbazone: applications in plasma vitamin B6 analysis and population surveys of vitamin B6 nutritional status. J Chromatogr B Bi...

A nitrogen-containing carbon (N-C) film was synthesized by pyrolysis of vapor phase polymerized polypyrrole (PPy). This carbon film exhibits excellent rate capability and cyclability as a lithium-ion battery anode. The reversible capacities are 908.4, 825.7, 664.0, 531.6, 415.5 and 325.9 mA h g(-1) at 1C, 2C, 5C, 10C, 20C and 40C, respectively.

There are 16 epsilon-amino groups of lysyl residues which are essential for the activity of ribulose-1,5-bisphosphate carboxylase/oxygenase. These lysyl residues formed a Schiff base with pyridoxal 5'-phosphate which was stabilized by NaBH4 reduction. The stoichiometry of covalently bound pyridoxal 5'-phosphate after NaBH4 reduction was determined spectrophotometrically with a derived molar ext...

Many compounds have been described that inhibit growth by interfering at one point or another in the metabolism of vitamin Bg (2). These include a variety of compounds related structurally to the vitamin, together with an array of carbonyl reagents generally known to inhibit pyridoxal phosphate enzymes. In no case has the site of action of such inhibitors in tivo been established. One of the fi...

Salt stress is a major environmental factor influencing plant growth and development. To identify salt tolerance determinants, a genetic screen for salt overly sensitive (sos) mutants was performed in Arabidopsis. We present here the characterization of sos4 mutants and the positional cloning of the SOS4 gene. sos4 mutant plants are hypersensitive to Na(+), K(+), and Li(+) ions. Under NaCl stre...

The unfolding of cytoplasmic aspartate aminotransferase from pig heart in solutions of guanidinium chloride (GdnHCl) was studied. Data from protein fluorescence, c.d. and thiol-group reactivity indicated that the enzyme was unfolded in 6 M-GdnHCl. Spectroscopic studies showed that this unfolding was accompanied by dissociation of the pyridoxal 5'-phosphate cofactor. On dilution of the GdnHCl, r...