1g77: Difference between revisions

[[Image:1g77.gif|left|200px]]<br /><applet load="1g77" size="350" color="white" frame="true" align="right" spinBox="true"  

Escherichia coli pyridoxine 5'-phosphate oxidase catalyzes the terminal step in the biosynthesis of pyridoxal 5'-phosphate by the FMN oxidation of pyridoxine 5'-phosphate forming FMNH(2) and H(2)O(2). Recent studies have shown that in addition to the active site, pyridoxine 5'-phosphate oxidase contains a non-catalytic site that binds pyridoxal 5'-phosphate tightly. The crystal structure of pyridoxine 5'-phosphate oxidase from E. coli with one or two molecules of pyridoxal 5'-phosphate bound to each monomer has been determined to 2.0 A resolution. One of the pyridoxal 5'-phosphate molecules is clearly bound at the active site with the aldehyde at C4' of pyridoxal 5'-phosphate near N5 of the bound FMN. A protein conformational change has occurred that partially closes the active site. The orientation of the bound pyridoxal 5'-phosphate suggests that the enzyme catalyzes a hydride ion transfer between C4' of pyridoxal 5'-phosphate and N5 of FMN. When the crystals are soaked with excess pyridoxal 5'-phosphate an additional molecule of this cofactor is also bound about 11 A from the active site. A possible tunnel exists between the two sites so that pyridoxal 5'-phosphate formed at the active site may transfer to the non-catalytic site without passing though the solvent.

1G77 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=PO4:'>PO4</scene>, <scene name='pdbligand=FMN:'>FMN</scene> and <scene name='pdbligand=PLP:'>PLP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Pyridoxal_5'-phosphate_synthase Pyridoxal 5'-phosphate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.4.3.5 1.4.3.5] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1G77 OCA].  

[[Category: Musayev, F N.]]

[[Category: Safo, M K.]]

[[Category: Salvo, M L.di.]]

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:46:51 2008''