1tzc: Difference between revisions
New page: left|200px<br /><applet load="1tzc" size="450" color="white" frame="true" align="right" spinBox="true" caption="1tzc, resolution 1.45Å" /> '''Crystal structure of... |
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[[Image:1tzc.jpg|left|200px]]<br /><applet load="1tzc" size=" | [[Image:1tzc.jpg|left|200px]]<br /><applet load="1tzc" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1tzc, resolution 1.45Å" /> | caption="1tzc, resolution 1.45Å" /> | ||
'''Crystal structure of phosphoglucose/phosphomannose isomerase from Pyrobaculum aerophilum in complex with 5-phosphoarabinonate'''<br /> | '''Crystal structure of phosphoglucose/phosphomannose isomerase from Pyrobaculum aerophilum in complex with 5-phosphoarabinonate'''<br /> | ||
==Overview== | ==Overview== | ||
The crystal structure of a dual specificity phosphoglucose isomerase | The crystal structure of a dual specificity phosphoglucose isomerase (PGI)/phosphomannose isomerase from Pyrobaculum aerophilum (PaPGI/PMI) has been determined in native form at 1.16-A resolution and in complex with the enzyme inhibitor 5-phosphoarabinonate at 1.45-A resolution. The similarity of its fold, with the inner core structure of PGIs from eubacterial and eukaryotic sources, confirms this enzyme as a member of the PGI superfamily. The almost total conservation of amino acids in the active site, including the glutamate base catalyst, shows that PaPGI/PMI uses the same catalytic mechanisms for both ring opening and isomerization for the interconversion of glucose 6-phosphate (Glc-6-P) to fructose 6-phosphate (Fru-6-P). The lack of structural differences between native and inhibitor-bound enzymes suggests this activity occurs without any of the conformational changes that are the hallmark of the well characterized PGI family. The lack of a suitable second base in the active site of PaPGI/PMI argues against a PMI mechanism involving a trans-enediol intermediate. Instead, PMI activity may be the result of additional space in the active site imparted by a threonine, in place of a glutamine in other PGI enzymes, which could permit rotation of the C-2-C-3 bond of mannose 6-phosphate. | ||
==About this Structure== | ==About this Structure== | ||
1TZC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pyrobaculum_aerophilum_str._im2 Pyrobaculum aerophilum str. im2] with SO4, PA5 and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | 1TZC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pyrobaculum_aerophilum_str._im2 Pyrobaculum aerophilum str. im2] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=PA5:'>PA5</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TZC OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Hansen, T.]] | [[Category: Hansen, T.]] | ||
[[Category: Schoenheit, P.]] | [[Category: Schoenheit, P.]] | ||
[[Category: Swan, M | [[Category: Swan, M K.]] | ||
[[Category: GOL]] | [[Category: GOL]] | ||
[[Category: PA5]] | [[Category: PA5]] | ||
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[[Category: pgi family]] | [[Category: pgi family]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:18:59 2008'' | ||
Revision as of 16:19, 21 February 2008
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Crystal structure of phosphoglucose/phosphomannose isomerase from Pyrobaculum aerophilum in complex with 5-phosphoarabinonate
OverviewOverview
The crystal structure of a dual specificity phosphoglucose isomerase (PGI)/phosphomannose isomerase from Pyrobaculum aerophilum (PaPGI/PMI) has been determined in native form at 1.16-A resolution and in complex with the enzyme inhibitor 5-phosphoarabinonate at 1.45-A resolution. The similarity of its fold, with the inner core structure of PGIs from eubacterial and eukaryotic sources, confirms this enzyme as a member of the PGI superfamily. The almost total conservation of amino acids in the active site, including the glutamate base catalyst, shows that PaPGI/PMI uses the same catalytic mechanisms for both ring opening and isomerization for the interconversion of glucose 6-phosphate (Glc-6-P) to fructose 6-phosphate (Fru-6-P). The lack of structural differences between native and inhibitor-bound enzymes suggests this activity occurs without any of the conformational changes that are the hallmark of the well characterized PGI family. The lack of a suitable second base in the active site of PaPGI/PMI argues against a PMI mechanism involving a trans-enediol intermediate. Instead, PMI activity may be the result of additional space in the active site imparted by a threonine, in place of a glutamine in other PGI enzymes, which could permit rotation of the C-2-C-3 bond of mannose 6-phosphate.
About this StructureAbout this Structure
1TZC is a Single protein structure of sequence from Pyrobaculum aerophilum str. im2 with , and as ligands. Full crystallographic information is available from OCA.
ReferenceReference
A novel phosphoglucose isomerase (PGI)/phosphomannose isomerase from the crenarchaeon Pyrobaculum aerophilum is a member of the PGI superfamily: structural evidence at 1.16-A resolution., Swan MK, Hansen T, Schonheit P, Davies C, J Biol Chem. 2004 Sep 17;279(38):39838-45. Epub 2004 Jul 13. PMID:15252053
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