Pyridoxal Kinase (PDXK)

Pyridoxal (pyridoxine, vitamin B6) kinase is also known as PDXK. The protein encoded by this gene phosphorylates vitamin B6, a step required for the conversion of vitamin B6 to pyridoxal-5-phosphate, an important cofactor in intermediary metabolism. The encoded protein is cytoplasmic and probably acts as a homodimer. Alternatively spliced transcript variants have been described, but their biological validity has not been determined.

Hanna et al. (1997) cloned the cDNA encoding PDXK, which they referred to as PKH. The PDXK gene encodes a 312-amino acid polypeptide, and expression of the cDNA revealed pyridoxal kinase activity. Northern blot analysis revealed that a major 1.5-kb PDXK transcript was expressed in all tissues tested.