|
|
| Line 1: |
Line 1: |
| [[Image:1mos.gif|left|200px]] | | {{Seed}} |
| | [[Image:1mos.png|left|200px]] |
|
| |
|
| <!-- | | <!-- |
| Line 9: |
Line 10: |
| {{STRUCTURE_1mos| PDB=1mos | SCENE= }} | | {{STRUCTURE_1mos| PDB=1mos | SCENE= }} |
|
| |
|
| '''ISOMERASE DOMAIN OF GLUCOSAMINE 6-PHOSPHATE SYNTHASE COMPLEXED WITH 2-AMINO-2-DEOXYGLUCITOL 6-PHOSPHATE'''
| | ===ISOMERASE DOMAIN OF GLUCOSAMINE 6-PHOSPHATE SYNTHASE COMPLEXED WITH 2-AMINO-2-DEOXYGLUCITOL 6-PHOSPHATE=== |
|
| |
|
|
| |
|
| ==Overview==
| | <!-- |
| Glucosamine 6-phosphate synthase converts fructose-6P into glucosamine-6P or glucose-6P depending on the presence or absence of glutamine. The isomerase activity is associated with a 40-kDa C-terminal domain, which has already been characterized crystallographically. Now the three-dimensional structures of the complexes with the reaction product glucose-6P and with the transition state analog 2-amino-2-deoxyglucitol-6P have been determined. Glucose-6P binds in a cyclic form whereas 2-amino-2-deoxyglucitol-6P is in an extended conformation. The information on ligand-protein interactions observed in the crystal structures together with the isotope exchange and site-directed mutagenesis data allow us to propose a mechanism of the isomerase activity of glucosamine-6P synthase. The sugar phosphate isomerization involves a ring opening step catalyzed by His504 and an enolization step with Glu488 catalyzing the hydrogen transfer from C1 to C2 of the substrate. The enediol intermediate is stabilized by a helix dipole and the epsilon-amino group of Lys603. Lys485 may play a role in deprotonating the hydroxyl O1 of the intermediate.
| | The line below this paragraph, {{ABSTRACT_PUBMED_10091662}}, adds the Publication Abstract to the page |
| | (as it appears on PubMed at http://www.pubmed.gov), where 10091662 is the PubMed ID number. |
| | --> |
| | {{ABSTRACT_PUBMED_10091662}} |
|
| |
|
| ==About this Structure== | | ==About this Structure== |
| Line 29: |
Line 33: |
| [[Category: Glutamine amidotransferase]] | | [[Category: Glutamine amidotransferase]] |
| [[Category: Transferase]] | | [[Category: Transferase]] |
| ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 01:31:59 2008'' | | |
| | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Jul 3 00:36:24 2008'' |
