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1jxa
From Proteopedia
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GLUCOSAMINE 6-PHOSPHATE SYNTHASE WITH GLUCOSE 6-PHOSPHATE
Overview
Glucosamine-6-phosphate synthase catalyses the first and rate-limiting step in hexosamine metabolism, converting fructose 6-phosphate into glucosamine 6-phosphate in the presence of glutamine. The crystal structure of the Escherichia coli enzyme reveals the domain organisation of the homodimeric molecule. The 18 A hydrophobic channel sequestered from the solvent connects the glutaminase and isomerase active sites, and provides a means of ammonia transfer from glutamine to sugar phosphate. The C-terminal decapeptide sandwiched between the two domains plays a central role in the transfer. Based on the structure, a mechanism of enzyme action and self-regulation is proposed. It involves large domain movements triggered by substrate binding that lead to the formation of the channel.
About this Structure
1JXA is a Single protein structure of sequence from Escherichia coli with as ligand. Active as Glutamine--fructose-6-phosphate transaminase (isomerizing), with EC number 2.6.1.16 Full crystallographic information is available from OCA.
Reference
Channeling of ammonia in glucosamine-6-phosphate synthase., Teplyakov A, Obmolova G, Badet B, Badet-Denisot MA, J Mol Biol. 2001 Nov 9;313(5):1093-102. PMID:11700065
Page seeded by OCA on Thu Feb 21 13:27:45 2008
