3w2f: Difference between revisions
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<StructureSection load='3w2f' size='340' side='right' caption='[[3w2f]], [[Resolution|resolution]] 1.76Å' scene=''> | <StructureSection load='3w2f' size='340' side='right' caption='[[3w2f]], [[Resolution|resolution]] 1.76Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
[[3w2f]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Pig Pig]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3W2F OCA]. <br> | <table><tr><td colspan='2'>[[3w2f]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Pig Pig]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3W2F OCA]. <br> | ||
<b>[[Ligand|Ligands:]]</b> <scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</scene><br> | </td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=NAD:NICOTINAMIDE-ADENINE-DINUCLEOTIDE'>NAD</scene><br> | ||
<b>[[Related_structure|Related:]]</b> [[1ndh|1ndh]], [[3w2e|3w2e]], [[3w2g|3w2g]], [[3w2h|3w2h]], [[3w2i|3w2i]], [[3w5h|3w5h]]< | <tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1ndh|1ndh]], [[3w2e|3w2e]], [[3w2g|3w2g]], [[3w2h|3w2h]], [[3w2i|3w2i]], [[3w5h|3w5h]]</td></tr> | ||
<b>Activity:</b> <span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span>< | <tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">CYB5R3, DIA1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9823 PIG])</td></tr> | ||
<b>Resources:</b> <span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3w2f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3w2f OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3w2f RCSB], [http://www.ebi.ac.uk/pdbsum/3w2f PDBsum]</span>< | <tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glucokinase Glucokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.2 2.7.1.2] </span></td></tr> | ||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3w2f FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3w2f OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3w2f RCSB], [http://www.ebi.ac.uk/pdbsum/3w2f PDBsum]</span></td></tr> | |||
<table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
NADH-Cytochrome b5 reductase (b5R), a flavoprotein consisting of NADH and flavin adenine dinucleotide (FAD) binding domains, catalyzes electron transfer from the two-electron carrier NADH to the one-electron carrier cytochrome b5 (Cb5). The crystal structures of both the fully reduced form and the oxidized form of porcine liver b5R were determined. In the reduced b5R structure determined at 1.68A resolution, the relative configuration of the two domains was slightly shifted in comparison with that of the oxidized form. This shift resulted in an increase in the solvent-accessible surface area of FAD and created a new hydrogen-bonding interaction between the N5 atom of the isoalloxazine ring of FAD and the hydroxyl oxygen atom of Thr66, which is considered to be a key residue in the release of a proton from the N5 atom. The isoalloxazine ring of FAD in the reduced form is flat as in the oxidized form and stacked together with the nicotinamide ring of NAD(+). Determination of the oxidized b5R structure, including the hydrogen atoms, determined at 0.78A resolution revealed the details of a hydrogen-bonding network from the N5 atom of FAD to His49 via Thr66. Both of the reduced and oxidized b5R structures explain how backflow in this catalytic cycle is prevented and the transfer of electrons to one-electron acceptors such as Cb5 is accelerated. Furthermore, crystallographic analysis by the cryo-trapping method suggests that re-oxidation follows a two-step mechanism. These results provide structural insights into the catalytic cycle of b5R. | NADH-Cytochrome b5 reductase (b5R), a flavoprotein consisting of NADH and flavin adenine dinucleotide (FAD) binding domains, catalyzes electron transfer from the two-electron carrier NADH to the one-electron carrier cytochrome b5 (Cb5). The crystal structures of both the fully reduced form and the oxidized form of porcine liver b5R were determined. In the reduced b5R structure determined at 1.68A resolution, the relative configuration of the two domains was slightly shifted in comparison with that of the oxidized form. This shift resulted in an increase in the solvent-accessible surface area of FAD and created a new hydrogen-bonding interaction between the N5 atom of the isoalloxazine ring of FAD and the hydroxyl oxygen atom of Thr66, which is considered to be a key residue in the release of a proton from the N5 atom. The isoalloxazine ring of FAD in the reduced form is flat as in the oxidized form and stacked together with the nicotinamide ring of NAD(+). Determination of the oxidized b5R structure, including the hydrogen atoms, determined at 0.78A resolution revealed the details of a hydrogen-bonding network from the N5 atom of FAD to His49 via Thr66. Both of the reduced and oxidized b5R structures explain how backflow in this catalytic cycle is prevented and the transfer of electrons to one-electron acceptors such as Cb5 is accelerated. Furthermore, crystallographic analysis by the cryo-trapping method suggests that re-oxidation follows a two-step mechanism. These results provide structural insights into the catalytic cycle of b5R. | ||
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From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
</div> | |||
== References == | == References == | ||
<references/> | <references/> | ||