Vitamin B6 Pyridoxine, Plasma

Vitamin B₆ occurs as an alcohol (pyridoxine), an aldehyde (pyridoxal), and an amine (pyridoxamine). These forms are phosphorylated in the 5′-position to produce the physiologically active coenzymes that are critical to their biological function. Eukaryotes cannot synthesize vitamin B₆ molecules from smaller compounds and as a result require dietary B₆ for the synthesis of 5′-phosphate vitamins. Pyridoxal 5’Phosphate (PLP), the most clinically significant coenzyme form of vitamin B₆, is the form most commonly measured in plasma.^1-3