Pyridoxal-5’ phosphate monohydrate (P5P)

Pyridoxal-phosphate

Pyridoxal-phosphate from xtal 3D bs 17

Pyridoxal phosphate (PLP) is the active form of vitamin B6 and serves as a crucial coenzyme in various biochemical reactions. It plays a pivotal role in amino acid metabolism, neurotransmitter synthesis, and other enzymatic processes.

Molecular and Structural Information

• Molecular Formula: C8H10NO6P
• Molecular Weight: 247.14 g/mol (computed by PubChem 2.2, PubChem release 2021.10.14)
• Synonyms:
  • Pyridoxal 5'-phosphate
  • Codecarboxylase
  • Pyridoxal 5-phosphate
  • Pyridoxal phosphate
  • CAS Number: 54-47-7

Description and biochemical role

Pyridoxal 5'-phosphate is a monophosphate ester obtained by the condensation of phosphoric acid with the primary hydroxy group of pyridoxal. It serves as a coenzyme for numerous enzymatic reactions, including:

• Transamination – Converts amino acids into keto acids.
• Decarboxylation – Synthesizes neurotransmitters like serotonin, dopamine, and gamma-aminobutyric acid (GABA).
• Deamination – Removes amino groups from amino acids.

PLP also participates in the metabolism of sphingolipids, aminolevulinic acid, and other compounds, highlighting its essential role in both central nervous system and peripheral metabolic pathways.

Biological functions

Pyridoxal phosphate is involved in critical physiological processes:

• Amino Acid Metabolism: Functions as a coenzyme for transaminases (aminotransferases), facilitating the transfer of amino groups.
• Neurotransmitter Synthesis: Essential for the conversion of levodopa to dopamine and glutamate to GABA.
• Vitamin B6 Metabolism: Transiently converts into pyridoxamine phosphate during amino acid transamination.

Sources and occurrence

Pyridoxal phosphate has been reported in several organisms, including:

• Escherichia coli (strain K12, MG1655)
• Saccharomyces cerevisiae
• Homo sapiens
• Arabidopsis thaliana

Clinical significance

Role in Health and Disease

Reduced levels of PLP in the brain have been linked to neurological dysfunction. It can be used as a dietary supplement in cases of vitamin B6 deficiency, which may result in symptoms like:

• Neurological disorders
• Impaired neurotransmitter synthesis
• Anemia

Medicinal applications

Pyridoxal phosphate has been investigated as a therapeutic agent for:

• Cardioprotection: Medicure's MC-1 drug leverages PLP to reduce heart damage during arterial blockages and subsequent surgical interventions.
• Neurological Disorders: PLP's role in neurotransmitter synthesis makes it a candidate for managing diseases like epilepsy and Parkinson's disease.

Research and clinical trials

Pyridoxal phosphate is an investigational drug with a maximum clinical trial phase of III. It has one investigational indication, as per Open Targets. Its role in various metabolic pathways has been extensively studied, contributing to a deeper understanding of its biochemical and clinical importance.

References

• PubChem: Pyridoxal Phosphate
• ChEBI Database: Pyridoxal Phosphate
• DrugBank: Medicure MC-1
• Yeast Metabolome Database: Saccharomyces cerevisiae Pyridoxal Phosphate
• LOTUS Database: Pyridoxal Phosphate Occurrence

See Also

• Vitamin B6
• Aminotransferase
• Gamma-aminobutyric acid (GABA)
• Neurotransmitter synthesis

Vitamins A Vitamin A B Biotin Vitamin B1 (see Thiamin) Vitamin B12 Vitamin B6 C Calcium Choline Chromium Copper Vitamin C D Vitamin D

E Energy Drinks Exercise and Athletic Performance Vitamin E F Fluoride Folate I Iodine Iron K Vitamin K

M Magnesium Multivitamin/mineral Supplements N Niacin P Pantothenic Acid Phosphorus Potassium Primary Mitochondrial Disorders R Riboflavin

S Selenium T Thiamin V Vitamin A Vitamin B1 (see Thiamin) Vitamin B12 Vitamin B6 Vitamin C Vitamin D Vitamin E Vitamin K Z Zinc