853645-22-4

Enzyme cofactor.Normal coenzyme form of Vitamin B6

ChEBI: Pyridoxal 5'-phosphate is the monophosphate ester obtained by condensation of phosphoric acid with the primary hydroxy group of pyridoxal. It has a role as a coenzyme, a human metabolite, an Escherichia coli metabolite, a Saccharomyces cerevisiae metabolite, a mouse metabolite, an EC 2.7.7.7 (DNA-directed DNA polymerase) inhibitor and a cofactor. It is a vitamin B6 phosphate, a member of methylpyridines, a monohydroxypyridine and a pyridinecarbaldehyde. It is functionally related to a pyridoxal. It is a conjugate acid of a pyridoxal 5'-phosphate(2-).

Pyridoxal 5′-phosphate (PLP) aids in carbohydrate and fat metabolism by serving as a cofactor. It is majorly responsible for catalyzing the enzymatic reactions involved in sphingolipid synthesis and neurotransmitter (dopamine and serotonin) synthesis. PLP is used in the studies of PLP-dependent enzyme active sites. PLP is also a cofactor for a wide range of enzymes including mitochondrial 5-Aminolevulinic acid synthase (ALAS) cysteine desulfurase, cystathionine γ-synthase (CGS), ornithine 4,5-aminomutase (OAM), and D-serine dehydratase.

Pyridoxal 5’-Phosphate(PLP) is also often employed as an inhibitor and site-directed, conformationally sensitive reporter group for studying the environment of reactive amino groups within proteins. PLP forms aldimine adducts that can be reduced with nucleophilic reducing reagents such as sodium borohydride or sodium cyanoborohydride. Solid PLP is light-sensitive, and solutions should be prepared fresh. There are four pKa values associated with this coenzyme: a pKa < 2.5 and another at 6.20 for the phosphate group, a pKa of 4.14 for the hydroxyl group, and a pKa of 8.69 for the pyridinium group.

A process for the synthesis ofpyridoxal5' -phosphate, comprising the steps of:
a) adding phenetidine into pyridoxal solution, and reacting to generate pyridoxal Schiff base;
b) adding pyridoxal Schiff base into ionic liquid, and stirring until the pyridoxal Schiff base is fully dissolved to obtain an ion mixed solution; adding pyridoxal Schiff base into ionic liquid, stirring at 35-45 ℃, and cooling the obtained ionic mixed solution to room temperature after the pyridoxal Schiff base is completely dissolved;
c) adding polyphosphoric acid into the ion mixed solution in which the pyridoxal Schiff base is dissolved, stirring for reaction, cooling after the reaction is finished, and separating out solids from the ion mixed solution; filtering solid particles separated out from the ion mixed solution, wherein the solid obtained by filtering is pyridoxal 5' -phosphate Schiff base, and the obtained liquid is phosphorus-containing ionic liquid; the weight ratio of pyridoxal Schiff base dissolved in the ion mixed solution to the polyphosphoric acid is within the range of 1:1-1:3, the reaction time is within the range of 8-12h, the reaction temperature is within the range of 25-40 ℃, and the temperature is reduced to 10 ℃ after the reaction is finished; the phosphorus-containing ionic liquid obtained by filtering can be recycled;
d) carrying out hydrolysis purification reaction on the pyridoxal 5 '-phosphate Schiff base obtained in the step c) to obtain a final product pyridoxal 5' -phosphate.

This vitamin B6-derived coenzyme (FWfree-acid = 247.14 g/mol; CAS 853645-22-4), often abbreviated PLP, plays a central role in metabolism. In addition to facilitating aminotransfer reactions, PLP is a coenzyme in reactions involving: (a) loss of the a-proton, resulting in racemization, cyclization, or b-elimination/replacement (e.g., alanine racemase, 1- aminocyclopropane-1-carboxylate synthase, and serine dehydratase, respectively); (b) loss of the a-carboxylate as carbon dioxide (e.g., glutamate decarboxylase); (c) removal/replacement of a group by aldol cleavage (e.g., threonine aldolase); and (d) catalysis via ketimine intermediates (e.g., selenocysteine lyase). PLP is also often employed as an inhibitor and site-directed, conformationally sensitive reporter group for studying the environment of reactive amino groups within proteins. PLP forms aldimine adducts that can be reduced with nucleophilic reducing reagents such as sodium borohydride or sodium cyanoborohydride. Solid PLP is light-sensitive, and solutions should be prepared fresh. There are four pKa values associated with this coenzyme: a pKa < 2.5 and another at 6.20 for the phosphate group, a pKa of 4.14 for the hydroxyl group, and a pKa of 8.69 for the pyridinium group. The coenzyme has an ultraviolet/visible spectrum: lmax = 330 nm and 388 nm (e = 2500 and 4900 M–1cm–1, respectively) in 50 mM phosphate buffer at pH 7.0; lmax = 305 nm and 388 nm (e = 1100 and 6550 M–1cm–1, respectively) in 100 mM NaOH. Pyridoxal 5’-phosphate may also be used as a photosensitizing agent to modify nearby aminoacyl residues (e.g., histidyl residues in 6- phosphogluconate dehydrogenase and tryptophanase). Target (s) : acetylcholinesterase; acetyl-CoA carboxylase; acetyl-CoA synthetase, or acetate:CoA ligase; N-acetylneuraminate 4-O- acetyltransferase; acyl-[acyl-carrier-protein]:UDP-N- acetylglucosamine O-acyltransferase, followed by NaBH4 reduction; acylphosphatase; adenylate cyclase (6-8); [b-adrenergic-receptor] kinase; alanine racemase; alcohol dehydrogenase, followed by NaBH4 reduction; alcohol sulfotransferase (170; aldose reductase ; allantoate deiminase; N- (5-amino-5-carboxypentanoyl) -L- cysteinyl-D-valine synthetase; 5-aminoleulinate synthase, in the presence of borohydride; aryl-acylamidase; aspartate carbamoyltransferase; aspartyl aminopeptidase; ATP- dependent deoxyribonuclease; BglI restriction endonuclease, type II site-specific deoxyribonuclease; biliverdin reductase; carbonic anhydrase, or carbonate dehydratase; casein kinase II; catechol O-methyltransferase; cathepsin B; cathepsin K ; cathepsin L; cathepsin S; Ca2+-transporting ATPase; cerebroside sulfotransferase; cholesterol monooxygenase, side-chain cleaving, or cytochrome P450scc; z- crystallin/NADPH:quinone oxidoreductase; cytosine deaminase ; dextransucrase; dipeptidyl-peptidase I, or cathepsin C; DNA-directed DNA polymerase; f29 DNA polymerase; DNA topoisomerase I; DNA topoisomerase II; dopa decarboxylase; estrone sulfotransferase; exodeoxyribonuclease V; F1 ATPase, or H+-transporting two-sector ATPase; fatty-acid synthase, at enoyl-[acyl-carrier protein] reductase ; fatty-acyl-CoA synthase, yeast, at 3-ketoacyl-[acyl-carrier protein] reductase step; flavin-containing monooxygenase; b- fructofuranosidase, or invertase; fructose-1,6-bisphosphate aldolase; fructose-6-phosphate 2-kinase/fructose-2,6- bisphosphatase; a1®3 fucosyltransferase; galactosylceramide sulfotransferase; glucan 1,4-a-glucosidase, or glucoamylase, weakly inhibited; glucose-6-phosphatase; glucose-1-phosphate adenylyltransferase; glucose-6-phosphate dehydrogenase; a- glucosidase; glucuronate reductase; glutamate decarboxylase ; glutamate dehydrogenase; glutathione-disulfide reductase ; glutathione synthetase, slowly inhibited; glyceraldehyde-3- phosphate dehydrogenase; glycerol-1,2-cyclic-phosphate phosphodiesterase; glycerol dehydrogenase; glycogen phosphorylase; glycolipid sulfotransferase; glycoprotein N- acetylglucosaminyltransferase; glycoprotein 6-a-L-fucosyltransferase ; glycoprotein galactosyltransferase; glycoprotein sialyltransferase; hemoglobin S polymerization; hexokinase; HIV (human immunodeficiency virus) reverse transcriptase; H+/K+- exchanging ATPase; homoserine kinase; H-transporting ATPase, chloroplast; 2’-hydroxybiphenyl-2-sulfinate desulfinase ; w-hydroxy-fatty-acid:NADP+ oxidoreductase; hydroxyindole-O- methyltransferase (acetylserotonin O-methyltransferase; hydroxymethylbilane synthase; 4-hydroxyphenylpyruvate dioxygenase; inositol-phosphate phosphatase; inositol-3- phosphate synthase, or inositol-1-phosphate synthase; integrase, HIV ; a-ketoglutarate carrier; a-ketoglutarate dehydrogenase; kynurenine 3-monooxygenase; lactate dehydrogenase; lactoylglutathione lyase, or glyoxalase I; malate dehydrogenase; malate synthase; methanol:5-hydroxybenzimidazolylcobamide Co- methyltransferase; mevalonate kinase; muri+ne leukemia virus reverse tr+ans+criptase; myosin ATPase; NAD (P) transhydrogenase ; Na/K-exchanging ATPase; neuraminidase; NMN nucleosidase, weakly inhibited; nucleoside-diphosphatase; pancreatic ribonuclease, or ribonuclease A; phenol 2- monooxygenase; phenol sulfotransferase, or aryl sulfotransferase ; phenylalanyl-tRNA synthetase; phosphoenolpyruvate carboxylase; phosphofructokinase; phosphogluconate dehydrogenase; phosphoglucose isomerase; 3- phosphoglycerate kinase; phospholipase C; phosphomevalonate kinase; phosphopantothenoylcysteine decarboxylase ; phosphoribulokinase; porphobilinogen synthase, or d- aminolevulinate dehydratase; pyridoxamine:oxaloacetate aminotransferase; pyridoxine 4-oxidase; pyruvate dehydrogenase; pyruvate kinase; pyruvate,orthophosphate dikinase; retinal oxidase; ribonuclease A; ribonucleoside-diphosphate reductase; ribosomal proteins ; ribulose-1,5-bisphosphate carboxylase; RNA-directed DNA polymerase, or reverse transcriptase; RNA polymerase ; serine-sulfate ammonia-lyase; starch phosphorylase; starch synthase; succinic-semialdehyde dehydrogenase; thiamin-phosphate pyrophosphorylase; thymidylate synthase ; tissue-specific transcription factor HNF1; tryptophanase ; tryptophan synthase; uracilylalanine synthase; urocanase; uroporphyrinogen-III synthase; xanthine dehydrogenase, Drosophila melanogaster.

Store at -20°C