1sp9
From Proteopedia
(New page: 200px<br /><applet load="1sp9" size="450" color="white" frame="true" align="right" spinBox="true" caption="1sp9, resolution 3.Å" /> '''4-Hydroxyphenylpyruvat...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1sp9.jpg|left|200px]]<br /><applet load="1sp9" size=" | + | [[Image:1sp9.jpg|left|200px]]<br /><applet load="1sp9" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1sp9, resolution 3.Å" /> | caption="1sp9, resolution 3.Å" /> | ||
'''4-Hydroxyphenylpyruvate Dioxygenase'''<br /> | '''4-Hydroxyphenylpyruvate Dioxygenase'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The transformation of 4-hydroxyphenylpyruvate to homogentisate, catalyzed | + | The transformation of 4-hydroxyphenylpyruvate to homogentisate, catalyzed by 4-hydroxyphenylpyruvate dioxygenase (HPPD), plays an important role in degrading aromatic amino acids. As the reaction product homogentisate serves as aromatic precursor for prenylquinone synthesis in plants, the enzyme is an interesting target for herbicides. In this study we report the first x-ray structures of the plant HPPDs of Zea mays and Arabidopsis in their substrate-free form at 2.0 A and 3.0 A resolution, respectively. Previous biochemical characterizations have demonstrated that eukaryotic enzymes behave as homodimers in contrast to prokaryotic HPPDs, which are homotetramers. Plant and bacterial enzymes share the overall fold but use orthogonal surfaces for oligomerization. In addition, comparison of both structures provides direct evidence that the C-terminal helix gates substrate access to the active site around a nonheme ferrous iron center. In the Z. mays HPPD structure this helix packs into the active site, sequestering it completely from the solvent. In contrast, in the Arabidopsis structure this helix tilted by about 60 degrees into the solvent and leaves the active site fully accessible. By elucidating the structure of plant HPPD enzymes we aim to provide a structural basis for the development of new herbicides. |
==About this Structure== | ==About this Structure== | ||
| - | 1SP9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana] with FE2 as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/4-hydroxyphenylpyruvate_dioxygenase 4-hydroxyphenylpyruvate dioxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.27 1.13.11.27] Full crystallographic information is available from [http:// | + | 1SP9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana] with <scene name='pdbligand=FE2:'>FE2</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/4-hydroxyphenylpyruvate_dioxygenase 4-hydroxyphenylpyruvate dioxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.27 1.13.11.27] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1SP9 OCA]. |
==Reference== | ==Reference== | ||
| Line 16: | Line 16: | ||
[[Category: Auerbach, G.]] | [[Category: Auerbach, G.]] | ||
[[Category: Freigang, J.]] | [[Category: Freigang, J.]] | ||
| - | [[Category: Fritze, I | + | [[Category: Fritze, I M.]] |
[[Category: Huber, R.]] | [[Category: Huber, R.]] | ||
[[Category: Linden, L.]] | [[Category: Linden, L.]] | ||
| Line 23: | Line 23: | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:03:51 2008'' |
Revision as of 13:03, 21 February 2008
|
4-Hydroxyphenylpyruvate Dioxygenase
Overview
The transformation of 4-hydroxyphenylpyruvate to homogentisate, catalyzed by 4-hydroxyphenylpyruvate dioxygenase (HPPD), plays an important role in degrading aromatic amino acids. As the reaction product homogentisate serves as aromatic precursor for prenylquinone synthesis in plants, the enzyme is an interesting target for herbicides. In this study we report the first x-ray structures of the plant HPPDs of Zea mays and Arabidopsis in their substrate-free form at 2.0 A and 3.0 A resolution, respectively. Previous biochemical characterizations have demonstrated that eukaryotic enzymes behave as homodimers in contrast to prokaryotic HPPDs, which are homotetramers. Plant and bacterial enzymes share the overall fold but use orthogonal surfaces for oligomerization. In addition, comparison of both structures provides direct evidence that the C-terminal helix gates substrate access to the active site around a nonheme ferrous iron center. In the Z. mays HPPD structure this helix packs into the active site, sequestering it completely from the solvent. In contrast, in the Arabidopsis structure this helix tilted by about 60 degrees into the solvent and leaves the active site fully accessible. By elucidating the structure of plant HPPD enzymes we aim to provide a structural basis for the development of new herbicides.
About this Structure
1SP9 is a Single protein structure of sequence from Arabidopsis thaliana with as ligand. Active as 4-hydroxyphenylpyruvate dioxygenase, with EC number 1.13.11.27 Full crystallographic information is available from OCA.
Reference
The crystal structures of Zea mays and Arabidopsis 4-hydroxyphenylpyruvate dioxygenase., Fritze IM, Linden L, Freigang J, Auerbach G, Huber R, Steinbacher S, Plant Physiol. 2004 Apr;134(4):1388-400. PMID:15084729
Page seeded by OCA on Thu Feb 21 15:03:51 2008
