View source for 4amv

==E.COLI GLUCOSAMINE-6P SYNTHASE IN COMPLEX WITH FRUCTOSE-6P==
<StructureSection load='4amv' size='340' side='right' caption='[[4amv]], [[Resolution|resolution]] 2.05&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4amv]] is a 3 chain structure with sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=2bpl 2bpl]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4AMV OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4AMV FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=F6R:FRUCTOSE+-6-PHOSPHATE'>F6R</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4amk|4amk]]</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glutamine--fructose-6-phosphate_transaminase_(isomerizing) Glutamine--fructose-6-phosphate transaminase (isomerizing)], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.6.1.16 2.6.1.16] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4amv FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4amv OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4amv RCSB], [http://www.ebi.ac.uk/pdbsum/4amv PDBsum]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/GLMS_ECOLI GLMS_ECOLI]] Catalyzes the first step in hexosamine metabolism, converting fructose-6P into glucosamine-6P using glutamine as a nitrogen source. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Glucosamine-6P synthase catalyzes the synthesis of glucosamine-6P from fructose-6P and glutamine and uses a channel to transfer ammonia from its glutaminase to its synthase active site. X-ray structures of glucosamine-6P synthase have been determined at 2.05 Angstroms resolution in the presence of fructose-6P and at 2.35 Angstroms resolution in the presence of fructose-6P and 6-diazo-5-oxo-L-norleucine, a glutamine affinity analog that covalently modifies the N-terminal catalytic cysteine, therefore mimicking the gamma-glutamyl-thioester intermediate formed during hydrolysis of glutamine. The fixation of the glutamine analog activates the enzyme through several major structural changes: 1) the closure of a loop to shield the glutaminase site accompanied by significant domain hinging, 2) the activation of catalytic residues involved in glutamine hydrolysis, i.e. the alpha-amino group of Cys-1 and Asn-98 that is positioned to form the oxyanion hole, and 3) a 75 degrees rotation of the Trp-74 indole group that opens the ammonia channel.

Glutamine binding opens the ammonia channel and activates glucosamine-6P synthase.,Mouilleron S, Badet-Denisot MA, Golinelli-Pimpaneau B J Biol Chem. 2006 Feb 17;281(7):4404-12. Epub 2005 Dec 9. PMID:16339762<ref>PMID:16339762</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Golinelli-Pimpaneau, B]]
[[Category: Mouilleron, S]]
[[Category: Ammonia channeling]]
[[Category: Glucosamine 6- phosphate synthase]]
[[Category: Glutamine amidotransferase]]
[[Category: N terminal nucleophile]]
[[Category: Transferase]]