6yk0
Crystal structure of mouse pyridoxal kinase in complex with ATP-gamma-SCrystal structure of mouse pyridoxal kinase in complex with ATP-gamma-S
Structural highlights
FunctionPDXK_MOUSE Catalyzes the phosphorylation of the dietary vitamin B6 vitamers pyridoxal (PL), pyridoxine (PN) and pyridoxamine (PM) to form pyridoxal 5'-phosphate (PLP), pyridoxine 5'-phosphate (PNP) and pyridoxamine 5'-phosphate (PMP), respectively (By similarity). PLP is the active form of vitamin B6, and acts as a cofactor for over 140 different enzymatic reactions (By similarity).[UniProtKB:O00764] Publication Abstract from PubMedThe antimalarial artemisinins have also been implicated in the regulation of various cellular pathways including immunomodulation of cancers and regulation of pancreatic cell signaling in mammals. Despite their widespread application, the cellular specificities and molecular mechanisms of target recognition by artemisinins remain poorly characterized. We recently demonstrated how these drugs modulate inhibitory postsynaptic signaling by direct binding to the postsynaptic scaffolding protein gephyrin. Here, we report the crystal structure of the central metabolic enzyme pyridoxal kinase (PDXK), which catalyzes the production of the active form of vitamin B6 (also known as pyridoxal 5'-phosphate [PLP]), in complex with artesunate at 2.4-A resolution. Partially overlapping binding of artemisinins with the substrate pyridoxal inhibits PLP biosynthesis as demonstrated by kinetic measurements. Electrophysiological recordings from hippocampal slices and activity measurements of glutamic acid decarboxylase (GAD), a PLP-dependent enzyme synthesizing the neurotransmitter gamma-aminobutyric acid (GABA), define how artemisinins also interfere presynaptically with GABAergic signaling. Our data provide a comprehensive picture of artemisinin-induced effects on inhibitory signaling in the brain. Pyridoxal kinase inhibition by artemisinins down-regulates inhibitory neurotransmission.,Kasaragod VB, Pacios-Michelena A, Schaefer N, Zheng F, Bader N, Alzheimer C, Villmann C, Schindelin H Proc Natl Acad Sci U S A. 2020 Dec 29;117(52):33235-33245. doi:, 10.1073/pnas.2008695117. Epub 2020 Dec 14. PMID:33318193[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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