3fhy

Publication Abstract from PubMed

Pyridoxal kinase catalyzes the phosphorylation of pyridoxal (PL) to pyridoxal 5'-phosphate (PLP). A D235A variant shows 7-fold and 15-fold decreases in substrate affinity and activity, respectively. A D235N variant shows approximately 2-fold decrease in both PL affinity and activity. The crystal structure of D235A (2.5 A) shows bound ATP, PL and PLP, while D235N (2.3 A) shows bound ATP and sulfate. These results document the role of Asp235 in PL kinase activity. The observation that the active site of PL kinase can accommodate both ATP and PLP suggests that formation of a ternary Enz.PLP.ATP complex could occur in the wild-type enzyme, consistent with severe MgATP substrate inhibition of PL kinase in the presence of PLP.

Kinetic and structural studies of the role of the active site residue Asp235 of human pyridoxal kinase.,Gandhi AK, Ghatge MS, Musayev FN, Sease A, Aboagye SO, di Salvo ML, Schirch V, Safo MK Biochem Biophys Res Commun. 2009 Mar 27;381(1):12-5. Epub 2009 Feb 4. PMID:19351586^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.