Pyridoxal-5’-phosphate monohydrate is a vitamin B6 metabolite that can modify lysyl and valyl residues in proteins. It has the ability to inhibit purinergic receptors and intracellular influx of Ca2+. Pyridoxal-5’-phosphate monohydrate can modify peptides and suppress their precursor ionization efficiency. Research shows that pyridoxal-5'-phosphate-dependent enzymes can be inhibited by cycloserine.A vitamin B6 metabolite that can modify lysyl and valyl residues in proteins. Pyridoxal-5’-phosphate monohydrate is a vitamin B6 metabolite that can modify lysyl and valyl residues in proteins. It has the ability to inhibit purinergic receptors and intracellular influx of Ca2+. Pyridoxal-5’-phosphate monohydrate can modify peptides and suppress their precursor ionization efficiency. Research shows that pyridoxal-5'-phosphate-dependent enzymes can be inhibited by cycloserine. A vitamin B6 metabolite that can modify lysyl and valyl residues in proteins.