Pyridoxal Phosphate

Synonyms :
Codecarboxylase, PLP, Pyridoxal 5-phosphate, Pyridoxal 5′-phosphate, Pyridoxal P, Pyridoxal-5P, Pyridoxal-P

Status : nutraceutical


Vitamin B Complex

Therapeutic Classification


Dietary Supplements


This is the active form of vitamin B6 serving as a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. During transamination of amino acids, pyridoxal phosphate is transiently converted into pyridoxamine phosphate (pyridoxamine). [PubChem]


For nutritional supplementation and for treating dietary shortage or imbalance.

Mechanism Of Action

Pyridoxal Phosphate is a coenzyme of many enzymatic reactions. It is the active form of vitamin B6 which comprises three natural organic compounds, pyridoxal, pyridoxamine and pyridoxine. Pyridoxal phosphate acts as a coenzyme in all transamination reactions, and in some decarboxylation and deamination reactions of amino acids. The aldehyde group of pyridoxal phosphate forms a Schiff-base linkage with the epsilon-amino group of a specific lysine group of the aminotransferase enzyme. The alpha-amino group of the amino acid substrate displaces the epsilon-amino group of the active-site lysine residue. The resulting aldimine becomes deprotonated to become a quinoid intermediate, which in turn accepts a proton at a different position to become a ketimine. The resulting ketimine is hydrolysed so that the amino group remains on the protein complex.


The two major forms of vitamin B6 are pyridoxine and pyridoxamine. In the liver they are converted to pyridoxal phosphate (PLP) which is a cofactor in many reactions of amino acid metabolism. PLP also is necessary for the enzymatic reaction governing the release of glucose from glycogen. Pyroluria is one potential cause of vitamin B6 deficiency.

Chemical Classification

This compound belongs to the class of organic compounds known as pyridoxals and derivatives. These are compounds containing a pyridoxal moiety, which consists of a pyridine ring substituted at positions 2,3,4, and 5 by a methyl group, a hydroxyl group, a carbaldehyde group, and a hydroxymethyl group, respectively.

Pyridoxals and derivatives

Organic compounds

Organoheterocyclic compounds

Pyridines and derivatives

Pyridine carboxaldehydes

Chemical Name


Calculated Property

kind Value Source
logP -0.55 ALOGPS
logS -1.6 ALOGPS
Water Solubility 5.70e+00 g/l ALOGPS
logP -2.1 ChemAxon
IUPAC Name [(4-formyl-5-hydroxy-6-methylpyridin-3-yl)methoxy]phosphonic acid ChemAxon
Traditional IUPAC Name pyridoxal phosphate ChemAxon
Molecular Weight 247.1419 ChemAxon
Monoisotopic Weight 247.024573569 ChemAxon
Molecular Formula C8H10NO6P ChemAxon
InChI InChI=1S/C8H10NO6P/c1-5-8(11)7(3-10)6(2-9-5)4-15-16(12,13)14/h2-3,11H,4H2,1H3,(H2,12,13,14) ChemAxon
Polar Surface Area (PSA) 116.95 ChemAxon
Refractivity 54.75 ChemAxon
Polarizability 20.9 ChemAxon
Rotatable Bond Count 4 ChemAxon
H Bond Acceptor Count 6 ChemAxon
H Bond Donor Count 3 ChemAxon
pKa (strongest acidic) 1.68 ChemAxon
pKa (strongest basic) 4.11 ChemAxon
Physiological Charge -2 ChemAxon
Number of Rings 1 ChemAxon
Bioavailability 1 ChemAxon
Rule of Five 1 ChemAxon
Ghose Filter 0 ChemAxon
MDDR-Like Rule 0 ChemAxon

Affected organism

Humans and other mammals

Target within organism

  • Alanine–glyoxylate aminotransferase 2, mitochondrial : in Human
  • Glutamate decarboxylase 1 : in Human
  • Cystathionine beta-synthase : in Human
  • Kynureninase : in Human
  • Serine hydroxymethyltransferase, cytosolic : in Human
  • Cysteine desulfurase, mitochondrial : in Human
  • Aspartate aminotransferase, cytoplasmic : in Human
  • Ornithine aminotransferase, mitochondrial : in Human
  • Ornithine decarboxylase : in Human
  • Kynurenine/alpha-aminoadipate aminotransferase, mitochondrial : in Human
  • 4-aminobutyrate aminotransferase, mitochondrial : in Human
  • Pyridoxine-5′-phosphate oxidase : in Human
  • Sphingosine-1-phosphate lyase 1 : in Human
  • Tyrosine aminotransferase : in Human
  • Kynurenine–oxoglutarate transaminase 1 : in Human
  • Threonine synthase-like 1 : in Human
  • Glycogen phosphorylase, liver form : in Human
  • Serine palmitoyltransferase 2 : in Human
  • Cysteine sulfinic acid decarboxylase : in Human
  • Histidine decarboxylase : in Human
  • Arginine decarboxylase : in Human
  • L-serine dehydratase/L-threonine deaminase : in Human
  • 2-amino-3-ketobutyrate coenzyme A ligase, mitochondrial : in Human
  • Glycine dehydrogenase [decarboxylating], mitochondrial : in Human
  • Alanine aminotransferase 1 : in Human
  • Phosphoserine aminotransferase : in Human
  • 5-aminolevulinate synthase, nonspecific, mitochondrial : in Human
  • Serine–pyruvate aminotransferase : in Human
  • Pyridoxal phosphate phosphatase : in Human
  • Serine palmitoyltransferase 1 : in Human
  • Cystathionine gamma-lyase : in Human
  • Branched-chain-amino-acid aminotransferase, cytosolic : in Human
  • Branched-chain-amino-acid aminotransferase, mitochondrial : in Human
  • Proline synthase co-transcribed bacterial homolog protein : in Human
  • Formimidoyltransferase-cyclodeaminase : in Human
  • Aspartate aminotransferase, mitochondrial : in Human
  • Glycogen phosphorylase, brain form : in Human
  • Glycogen phosphorylase, muscle form : in Human
  • Aromatic-L-amino-acid decarboxylase : in Human
  • Serine hydroxymethyltransferase, mitochondrial : in Human
  • Aspartate aminotransferase : in Human
  • GAD1 protein : in Human
  • Serine hydroxymethyltransferase : in Human
  • Selenocysteine lyase variant : in Human
  • Phosphorylase : in Human
  • Ornithine aminotransferase variant : in Human
  • Serine hydroxymethyltransferase, cytosolic : in Human
  • Serine hydroxymethyltransferase, cytosolic : in Human
  • 5-aminolevulinate synthase : in Human
  • Glutamate decarboxylase 2 (Pancreatic islets and brain, 65kDa) : in Human
  • DDC protein : in Human
  • Pyridoxal-dependent decarboxylase domain-containing protein 1 : in Human
  • Kynurenine–oxoglutarate transaminase 3 : in Human
  • Glutamate decarboxylase-like protein 1 : in Human
  • Selenocysteine lyase : in Human
  • Immunoglobulin superfamily member 10 : in Human
  • 5-phosphohydroxy-L-lysine phospho-lyase : in Human
  • Glutamate decarboxylase 1 (Brain, 67kDa) : in Human
  • Serine hydroxymethyltransferase, mitochondrial : in Human
  • Alanine aminotransferase 2 : in Human
  • Molybdenum cofactor sulfurase : in Human
  • Serine dehydratase-like : in Human
  • P-selectin cytoplasmic tail-associated protein (PCAP) : in Human
  • Hepatic peroxysomal alanine:glyoxylate aminotransferase : in Human
  • Serine racemase : in Human
  • O-phosphoseryl-tRNA(Sec) selenium transferase : in Human
  • Serine palmitoyltransferase 3 : in Human
  • Glutamic acid decarboxylase : in Human
  • Alanine-glyoxylate aminotransferase homolog : in Human
  • Cysteine sulfinic acid decarboxylase : in Human