2.7.1.35 evolution PdxK belongs to ribokinase enzyme family in which either cysteine or aspartate act as catalytic residue for its activity. The known catalytic mechanism of ribokinase family and for PdxK is the in line displacement mechanism in which hydroxyl group of the substrate is activated by a catalytic base (aspartate) of the enzyme, to make the nucleophilic attack on the gamma-phosphate group of ATP. The active site residues Leu43, Ser47, Ile52, Arg56, Asn87 and Thr227 present in LdPdxK are replaced with Phe43, Thr47, Try52, Val56, Arg86 and Val231 in mammalian PdxKs -, 759346 2.7.1.35 evolution pyridoxine/pyridoxal kinase (PdxK) belongs to the ribokinase family and is involved in the vitamin B6 salvage pathway by phosphorylating pyridoxal (PL) into an active form. In the human malaria parasite, Plasmodium falciparum, PfPdxK functions to salvage vitamin B6 from both itself and its host 759093 2.7.1.35 malfunction in Drosophila, mutations in the dPdxk gene cause chromosome aberrations (CABs) and increased glucose content in larval hemolymph. The phenotype is rescued by the expression of wild-type human PDXK enzyme, although not by human PDXK mutants D87H, V128I, H246Q, and A243G 760178 2.7.1.35 malfunction root growth of a sos4 mutant is significantly decreased when grown on either 100 mM or 200 mM sucrose as compared to root growth on10 mM sucrose. The sos4 mutant plant accumulates phytoglycogen 723449 2.7.1.35 malfunction the four PDXK human variants, D87H, V128I, H246Q, and A243Gf D87H, V128I, H246Q and A243G proteins show reduced catalytic activity and/or reduced affinity for PLP precursors. Although these variants are rare in population and carried in heterozygous condition, it is suggested that in certain metabolic contexts and diseases in which PLP levels are reduced, the presence of these PDXK variants might threaten genome integrity and increase cancer risk 760178 2.7.1.35 additional information a FIxxIIxL motif at the C-terminus of the disordered repeat motif (XNXH)m that is implicated in binding the WD40 domain and may provide temporal control of PfPdxK through an interaction with a E3 ligase complex. Molecular docking and modelling, overview. Binding structure of AMP-PNP with PdxK 759093 2.7.1.35 additional information analysis of the binding structures of substrates and products from PdxK-ligand crystal structures, overview -, 759346 2.7.1.35 additional information comparison of the structure of apo StPLK with its ligand-bound forms 759183 2.7.1.35 additional information experimental resurrection of the last common ancestor of the hydroxymethyl pyrimidine kinase group based on comparison of hydroxymethyl pyrimidine and pyridoxal kinases. Probably the last common ancestor was not able to use pyridoxal under physiological conditions. The pyridoxal kinase activity present in the current bifunctional enzymes must have appeared in a convergent event independently of the pyridoxal kinase activity of pdxY and pdxK genes. Substrate pyridoxal is 8-times less preferred than the phosphorylation of hydroxymethyl pyrimidine by the last ancestor 738234 2.7.1.35 additional information in silico analysis of the human and parasite PdxK structure revealing significant differences in the active site region, LdPdxK homology modeling using pyridoxal kinase from Trypanosoma brucei (PDB ID 3ZS7) as a template, molecular dynamics and molecular docking, overview -, 759342 2.7.1.35 physiological function biotransformation of pyridoxal to pyridoxal 5'-phosphate (PLP) by pyridoxal kinase (pdxY) supports cadaverine production in Escherichia coli. PLP is an essential cofactor of lysine decarboxylase and the major bottleneck in the cadaverine biosynthesis pathway 759126 2.7.1.35 physiological function in eukaryotes, pyridoxal kinase (PDXK) acts in vitamin B6 salvage pathway to produce pyridoxal 5'-phosphate (PLP), the active form of the vitamin, which is implicated in numerous crucial metabolic reactions. PDXK converts PLP precursors such as pyridoxal (PL), pyridoxamine (PM) and pyridoxine (PN) taken from food into PLP, PMP and PNP, respectively. PNPO catalyzes the oxidation of PMP and PNP into PLP. PLP performs many functions by working as coenzyme for a wide number of enzymes which control amino acid, lipid and carbohydrate metabolism 760178 2.7.1.35 physiological function pyridoxal kinase (PdxK) is an important enzyme of the vitamin B6 salvage pathway which is required for phosphorylation of B6 vitamers -, 759342 2.7.1.35 physiological function pyridoxal kinase is a key enzyme in the metabolism of vitamin B6 722183 2.7.1.35 physiological function pyridoxine/pyridoxal kinase (PdxK) belongs to the ribokinase family and is involved in the vitamin B6 salvage pathway by phosphorylating pyridoxal (PL) into an active form. In the human malaria parasite, Plasmodium falciparum, PfPdxK functions to salvage vitamin B6 from both itself and its host 759093 2.7.1.35 physiological function the enzyme is essential for growth of Trypanosoma brucei in vitro and for infectivity in mice 723219 2.7.1.35 physiological function the enzyme pyridoxal kinase (PdxK) catalyzes the conversion of pyridoxal to pyridoxal 5'-phosphate (PLP) using ATP as the cosubstrate. The product PLP plays a key role in several biological processes such as transamination, decarboxylation and deamination -, 759346 2.7.1.35 physiological function the SOS4 pyridoxal kinase is required for maintenance of vitamin B6-mediated processes in chloroplasts. SOS4 is required for maintenance of phosphorylated B6 vitamer concentrations in chloroplasts 723449 2.7.1.35 physiological function vitamin B6 enters the cells after hydrolysis of the phosphorylated forms by the membrane-bound tissue non-specific alkaline phosphatase (TNSALP, EC 3.1.3.1). Once inside the cells, pyridoxal kinase (PL kinase, PDXK, EC 2.7.1.35) phosphorylates the hydroxymethyl group of PL, PN and PM to their respective 5'-phosphate forms 758844