1eyj
From Proteopedia
(New page: 200px<br /><applet load="1eyj" size="450" color="white" frame="true" align="right" spinBox="true" caption="1eyj, resolution 2.28Å" /> '''FRUCTOSE-1,6-BISPHOS...) |
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| - | [[Image:1eyj.jpg|left|200px]]<br /><applet load="1eyj" size=" | + | [[Image:1eyj.jpg|left|200px]]<br /><applet load="1eyj" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1eyj, resolution 2.28Å" /> | caption="1eyj, resolution 2.28Å" /> | ||
'''FRUCTOSE-1,6-BISPHOSPHATASE COMPLEX WITH AMP, MAGNESIUM, FRUCTOSE-6-PHOSPHATE AND PHOSPHATE (T-STATE)'''<br /> | '''FRUCTOSE-1,6-BISPHOSPHATASE COMPLEX WITH AMP, MAGNESIUM, FRUCTOSE-6-PHOSPHATE AND PHOSPHATE (T-STATE)'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Crystal structures of metal-product complexes of fructose 1, 6-bisphosphatase (FBPase) reveal competition between AMP and divalent | + | Crystal structures of metal-product complexes of fructose 1, 6-bisphosphatase (FBPase) reveal competition between AMP and divalent cations. In the presence of AMP, the Zn(2+)-product and Mg(2+)-product complexes have a divalent cation present only at one of three metal binding sites (site 1). The enzyme is in the T-state conformation with a disordered loop of residues 52-72 (loop 52-72). In the absence of AMP, the enzyme crystallizes in the R-state conformation, with loop 52-72 associated with the active site. In structures without AMP, three metal-binding sites are occupied by Zn(2+) and two of three metal sites (sites 1 and 2) by Mg(2+). Evidently, the association of AMP with FBPase disorders loop 52-72, the consequence of which is the release of cations from two of three metal binding sites. In the Mg(2+) complexes (but not the Zn(2+) complexes), the 1-OH group of fructose 6-phosphate (F6P) coordinates to the metal at site 1 and is oriented for a nucleophilic attack on the bound phosphate molecule. A mechanism is presented for the forward reaction, in which Asp74 and Glu98 together generate a hydroxide anion coordinated to the Mg(2+) at site 2, which then displaces F6P. Development of negative charge on the 1-oxygen of F6P is stabilized by its coordination to the Mg(2+) at site 1. |
==About this Structure== | ==About this Structure== | ||
| - | 1EYJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with F6P, MG, PO4 and AMP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Fructose-bisphosphatase Fructose-bisphosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.3.11 3.1.3.11] Full crystallographic information is available from [http:// | + | 1EYJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Sus_scrofa Sus scrofa] with <scene name='pdbligand=F6P:'>F6P</scene>, <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=PO4:'>PO4</scene> and <scene name='pdbligand=AMP:'>AMP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Fructose-bisphosphatase Fructose-bisphosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.3.11 3.1.3.11] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EYJ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Sus scrofa]] | [[Category: Sus scrofa]] | ||
[[Category: Choe, J.]] | [[Category: Choe, J.]] | ||
| - | [[Category: Honzatko, R | + | [[Category: Honzatko, R B.]] |
[[Category: AMP]] | [[Category: AMP]] | ||
[[Category: F6P]] | [[Category: F6P]] | ||
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[[Category: gluconeogenesis]] | [[Category: gluconeogenesis]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:32:52 2008'' |
Revision as of 10:32, 21 February 2008
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FRUCTOSE-1,6-BISPHOSPHATASE COMPLEX WITH AMP, MAGNESIUM, FRUCTOSE-6-PHOSPHATE AND PHOSPHATE (T-STATE)
Overview
Crystal structures of metal-product complexes of fructose 1, 6-bisphosphatase (FBPase) reveal competition between AMP and divalent cations. In the presence of AMP, the Zn(2+)-product and Mg(2+)-product complexes have a divalent cation present only at one of three metal binding sites (site 1). The enzyme is in the T-state conformation with a disordered loop of residues 52-72 (loop 52-72). In the absence of AMP, the enzyme crystallizes in the R-state conformation, with loop 52-72 associated with the active site. In structures without AMP, three metal-binding sites are occupied by Zn(2+) and two of three metal sites (sites 1 and 2) by Mg(2+). Evidently, the association of AMP with FBPase disorders loop 52-72, the consequence of which is the release of cations from two of three metal binding sites. In the Mg(2+) complexes (but not the Zn(2+) complexes), the 1-OH group of fructose 6-phosphate (F6P) coordinates to the metal at site 1 and is oriented for a nucleophilic attack on the bound phosphate molecule. A mechanism is presented for the forward reaction, in which Asp74 and Glu98 together generate a hydroxide anion coordinated to the Mg(2+) at site 2, which then displaces F6P. Development of negative charge on the 1-oxygen of F6P is stabilized by its coordination to the Mg(2+) at site 1.
About this Structure
1EYJ is a Single protein structure of sequence from Sus scrofa with , , and as ligands. Active as Fructose-bisphosphatase, with EC number 3.1.3.11 Full crystallographic information is available from OCA.
Reference
Crystal structures of fructose 1,6-bisphosphatase: mechanism of catalysis and allosteric inhibition revealed in product complexes., Choe JY, Fromm HJ, Honzatko RB, Biochemistry. 2000 Jul 25;39(29):8565-74. PMID:10913263
Page seeded by OCA on Thu Feb 21 12:32:52 2008
Categories: Fructose-bisphosphatase | Single protein | Sus scrofa | Choe, J. | Honzatko, R B. | AMP | F6P | MG | PO4 | Allosteric enzymes | Bisphosphatase | Gluconeogenesis
