Pyridoxal kinase (PdxK, EC 220.127.116.11) is an important enzyme of the vitamin B6 salvage pathway which is required for phosphorylation of B6 vitamers. PDXK belongs to the phosphotransferase family of enzymes and catalyzes the conversion of the three active forms of vitamin B6, pyridoxine, pyridoxal, and pyridoxamine, to their phosphorylated forms and thereby plays a key role in pyridoxal 5'-phosphate salvage. Pyridoxal kinase (PDXK) catalyzes the phosphorylation of pyridoxal, pyridoxamine, and pyridoxine in the presence of ATP and Zn2+. This constitutes an essential step in the synthesis of pyridoxal 5'-phosphate (PLP), the active form of vitamin B6, a cofactor for over 140 enzymes. In Drosophila, mutations in the dPdxk gene cause chromosome aberrations (CABs) and increase glucose content in larval hemolymph. Both phenotypes are rescued by the expression of the wild type human PDXK counterpart.