Disease relevance of PDXK

• Pyridoxal kinase from Escherichia coli and bakers' yeast was inactivated by pyridoxal while the enzyme from rat and pig brain was not [1].

High impact information on PDXK

• Structural analysis revealed that these three roscovitines bind similarly in the pyridoxal-binding site of PDXK rather than in the anticipated ATP-binding site [2].
• Affinity chromatography investigations have shown that (R)-roscovitine also interacts with PDXK [2].
• Pyridoxal kinase (PDXK) catalyzes the phosphorylation of pyridoxal, pyridoxamine, and pyridoxine in the presence of ATP and Zn2+ [2].
• N-Dansyl-2-oxopyrrolidine, a competitive inhibitor with respect to ATP, was used as a probe of the nucleotide binding site of pyridoxal kinase [3].
• With Mg(II), pyridoxal kinase exhibits stereoselectivity for the A diastereomer of ATP beta S, Vmax ratio, A/B = 30 [3].

Biological context of PDXK

• Nucleoside phosphorothioates as probes of the nucleotide binding site of brain pyridoxal kinase [3].
• It is postulated that histidine is involved in the binding of the substrate ATP to the catalytic site of pyridoxal kinase [4].
• Brain pyridoxal kinase. Purification, substrate specificities, and sensitized photodestruction of an essential histidine [4].
• Solution phase affinity measurement based on a competitive binding assay was used to determine the affinities of PK for different vitamin B(6) analogues [5].

Anatomical context of PDXK

• Transport of [3H]pyridoxine was studied with membrane vesicles prepared from brush border of guinea pig jejunum, in which pyridoxal kinase was not detected [6].

Associations of PDXK with chemical compounds

• Interaction between pyridoxal kinase and pyridoxal-5-phosphate-dependent enzymes [7].
• It could also aid in the design of roscovitine derivatives displaying strict selectivity for either PDXK or CDKs [2].
• Pyridoxal kinase, 60,000 molecular weight, catalyzes the phosphorylation of pyridoxal (Km = 2.5 x 10(-5) M) and pyridoxine (Km = 1.7 x 10(-5) M) [4].
• Interaction between pyridoxal kinase and pyridoxine-5-P oxidase, two enzymes involved in the metabolism of vitamin B6 [8].
• Brain pyridoxal kinase. Mechanism of substrate addition, binding of ATP, and rotational mobility of the inhibitor pyridoxaloxime [9].

Regulatory relationships of PDXK

• Since the concentration of free Zn++ in mammalian tissues is lower than 10(-9)M, it is postulated that the concentration of metallothionein regulates the catalytic activity of pyridoxal kinase [10].

Other interactions of PDXK

• Moreover, binding profiles of both enzymes to immobilized PK were altered by excess amount of PLP [7].
• The apoprotein of metallothionein as well as the peptide LYS-CYS-THR-CYS-CYS-ALA exert a strong inhibitory effect upon pyridoxal kinase by sequestering free Zn ions [10].

Analytical, diagnostic and therapeutic context of PDXK

• The interactions of two pyridoxal-5-phosphate (PLP)-dependent enzymes, alanine aminotransferase (ALT) and glutamate decarboxylase (GAD), with pyridoxal kinase (PK) were studied by fluorescence polarization as well as surface plasmon resonance techniques [7].
• Study of substrate-enzyme interaction between immobilized pyridoxamine and recombinant porcine pyridoxal kinase using surface plasmon resonance biosensor [5].

References