2pbj
From Proteopedia
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| - | [[Image:2pbj.jpg|left|200px]] | + | [[Image:2pbj.jpg|left|200px]] |
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| - | '''GSH-heme bound microsomal prostaglandin E synthase''' | + | {{Structure |
| + | |PDB= 2pbj |SIZE=350|CAPTION= <scene name='initialview01'>2pbj</scene>, resolution 2.8Å | ||
| + | |SITE= <scene name='pdbsite=AC1:Cl+Binding+Site+For+Residue+A+475'>AC1</scene>, <scene name='pdbsite=AC2:Cl+Binding+Site+For+Residue+B+475'>AC2</scene>, <scene name='pdbsite=AC3:Cl+Binding+Site+For+Residue+C+475'>AC3</scene>, <scene name='pdbsite=AC4:Cl+Binding+Site+For+Residue+D+475'>AC4</scene>, <scene name='pdbsite=AC5:Hem+Binding+Site+For+Residue+A+476'>AC5</scene>, <scene name='pdbsite=AC6:Gsh+Binding+Site+For+Residue+A+477'>AC6</scene>, <scene name='pdbsite=AC7:Hem+Binding+Site+For+Residue+B+476'>AC7</scene>, <scene name='pdbsite=AC8:Gsh+Binding+Site+For+Residue+B+477'>AC8</scene>, <scene name='pdbsite=AC9:Hem+Binding+Site+For+Residue+C+476'>AC9</scene>, <scene name='pdbsite=BC1:Gsh+Binding+Site+For+Residue+C+477'>BC1</scene>, <scene name='pdbsite=BC2:Hem+Binding+Site+For+Residue+D+476'>BC2</scene> and <scene name='pdbsite=BC3:Gsh+Binding+Site+For+Residue+D+477'>BC3</scene> | ||
| + | |LIGAND= <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene> and <scene name='pdbligand=GSH:GLUTATHIONE'>GSH</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Prostaglandin-E_synthase Prostaglandin-E synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=5.3.99.3 5.3.99.3] | ||
| + | |GENE= mPGES-2 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9541 Macaca fascicularis]) | ||
| + | }} | ||
| + | |||
| + | '''GSH-heme bound microsomal prostaglandin E synthase''' | ||
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==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 2PBJ is a [ | + | 2PBJ is a [[Single protein]] structure of sequence from [http://en.wikipedia.org/wiki/Macaca_fascicularis Macaca fascicularis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2PBJ OCA]. |
==Reference== | ==Reference== | ||
| - | PGH2 degradation pathway catalyzed by GSH-heme complex bound microsomal prostaglandin E2 synthase type 2: the first example of a dual-function enzyme., Yamada T, Takusagawa F, Biochemistry. 2007 Jul 17;46(28):8414-24. Epub 2007 Jun 22. PMID:[http:// | + | PGH2 degradation pathway catalyzed by GSH-heme complex bound microsomal prostaglandin E2 synthase type 2: the first example of a dual-function enzyme., Yamada T, Takusagawa F, Biochemistry. 2007 Jul 17;46(28):8414-24. Epub 2007 Jun 22. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/17585783 17585783] |
[[Category: Macaca fascicularis]] | [[Category: Macaca fascicularis]] | ||
[[Category: Prostaglandin-E synthase]] | [[Category: Prostaglandin-E synthase]] | ||
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[[Category: prostaglandin e synthase]] | [[Category: prostaglandin e synthase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 18:11:11 2008'' |
Revision as of 16:11, 20 March 2008
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| , resolution 2.8Å | |||||||
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| Sites: | , , , , , , , , , , and | ||||||
| Ligands: | , and | ||||||
| Gene: | mPGES-2 (Macaca fascicularis) | ||||||
| Activity: | Prostaglandin-E synthase, with EC number 5.3.99.3 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
GSH-heme bound microsomal prostaglandin E synthase
Overview
Prostaglandin E2 synthase (PGES) catalyzes the isomerization of PGH2 to PGE2. PGES type 2 (mPGES-2) is a membrane-associated enzyme, whose N-terminal section is apparently inserted into the lipid bilayer. Both intact and N-terminal truncated enzymes have been isolated and have similar catalytic activity. The recombinant N-terminal truncated enzyme purified from Escherichia coli HB101 grown in LB medium containing delta-aminolevulinate and Fe(NO3)3 has a red color, while the same enzyme purified from the same E. coli grown in minimal medium has no color. The red-colored enzyme has been characterized by mass, fluorescence, and EPR spectroscopies and X-ray crystallography. The enzyme is found to contain bound glutathione (GSH) and heme. GSH binds to the active site with six H-bonds, while a heme is complexed with bound GSH forming a S-Fe coordination bond with no polar interaction with mPGES-2. There is a large open space between the heme and the protein, where a PGH2 might be able to bind. The heme dissociation constant is 0.53 microM, indicating that mPGES-2 has relatively strong heme affinity. Indeed, expression of mPGES-2 in E. coli stimulates heme biosynthesis. Although mPGES-2 has been reported to be a GSH-independent PGES, the crystal structure and sequence analysis indicate that mPGES-2 is a GSH-binding protein. The GSH-heme complex-bound enzyme (mPGES-2h) catalyzes formation of 12(S)-hydroxy-5(Z),8(E),10(E)-heptadecatrienoic acid and malondialdehyde from PGH2, but not formation of PGE2. The following kinetic parameters at 37 degrees C were determined: KM = 56 microM, kcat = 63 s-1, and kcat/KM = 1.1 x 10(6) M-1 s-1. They suggest that mPGES-2h has significant catalytic activity for PGH2 degradation. It is possible that both GSH-heme complex-free and -bound enzymes are present in the same tissues. mPGES-2 in heme-rich liver is most likely to become the form of mPGES-2h and might be involved in degradation reactions similar to that of cytochrome P450. Since mPGES-2 is an isomerase and mPGES-2h is a lyase, mPGES-2 cannot simply be classified into one of six classes set by the International Union of Biochemistry and Molecular Biology.
About this Structure
2PBJ is a Single protein structure of sequence from Macaca fascicularis. Full crystallographic information is available from OCA.
Reference
PGH2 degradation pathway catalyzed by GSH-heme complex bound microsomal prostaglandin E2 synthase type 2: the first example of a dual-function enzyme., Yamada T, Takusagawa F, Biochemistry. 2007 Jul 17;46(28):8414-24. Epub 2007 Jun 22. PMID:17585783
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