In Escherichia coli, quinolinic acid, a precursor of NAD+, is synthesized from L-aspartate and dihydroxyacetone phosphate. This synthesis requires two enzymes, a FAD-containing "B protein" and an "A protein." The B protein has been purified 500-fold from E. coli cells. The enzyme behaves as an L-aspartate oxidase. In the absence of A protein, it converts L-aspartate to oxaloacetate. To our know...

Coffee is known as one of the most popular beverages around world. belongs to botanical family Rubiaceae and genus coffea. The two economically important species are C. arabica (arabica coffee) canephora (robusta coffee).The health benefits coffee due presence many biologically active components such caffeine, chlorogenic acid, nicotinic quinolinic trigonelline, tannic pyrogolic acid. postharve...

NADP is essential for biosynthetic pathways, energy, and signal transduction. In living organisms, NADP biosynthesis proceeds through the phosphorylation of NAD with a reaction catalyzed by NAD kinase. We expressed, purified, and characterized Bacillus subtilis NAD kinase. This enzyme represents a new member of the inorganic polyphosphate [poly(P)]/ATP NAD kinase subfamily, as it can use poly(P...

Phosphatidylinositol metabolism, linked to muscarinic receptor activation, was studied in rat cortical slices after a unilateral quinolinic acid lesion to the nucleus basalis magnocellularis (nbM) or the cortex itself. The incorporation of [3H]inositol into inositol phosphate was measured in the presence of LiCl, followed by anion exchange chromatography to separate inositol phosphates. Carbach...

this study sought to investigate the effects of two tomato varieties [Lycopersicon esculentum Mill. var. esculentum (Esc) and Lycopersicon esculentum Mill. var. cerasiforme (cEr)] on acetylcholinesterase (AchE) and butyrylcholinesterase (bchE) activities in vitro. Phenolics content, carotenoids characterisation, inhibition of Fe2+ and quinolinic acid-induced malondialdehyde (MDA) production in ...

Neurologic symptoms and neurodegeneration are important causes of morbidity and mortality in man. Although many pathogenic mechanisms could account for neurologic dysfunction, considerable interest has focused on a group of neurotoxins known as the ‘excitotoxins’. Quinolinic acid (QUIN) is an excitotoxic L-tryptophan and kynurenine pathway metabolite that is an agonist of N-methyl-uaspartate (N...

Rat liver tyrosine aminotransferase (L-tyrosine:2oxoglutarate aminotransferase; EC 2.6.1.5.) has been studied thoroughly with respect to its inducibility by various hormones. Recently, it has been shown that this enzyme can be stimulated by cyclic AMP 1 and by theophylline 2, which is capable of elevating intracellular levels of cyclic purine nucleotides. Moreover, this enzyme was shown to be i...