1a4e
From Proteopedia
(New page: 200px<br /><applet load="1a4e" size="450" color="white" frame="true" align="right" spinBox="true" caption="1a4e, resolution 2.4Å" /> '''CATALASE A FROM SACCH...) |
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| - | [[Image:1a4e.gif|left|200px]]<br /><applet load="1a4e" size=" | + | [[Image:1a4e.gif|left|200px]]<br /><applet load="1a4e" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1a4e, resolution 2.4Å" /> | caption="1a4e, resolution 2.4Å" /> | ||
'''CATALASE A FROM SACCHAROMYCES CEREVISIAE'''<br /> | '''CATALASE A FROM SACCHAROMYCES CEREVISIAE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The structure of the peroxisomal catalase A from the budding yeast | + | The structure of the peroxisomal catalase A from the budding yeast Saccharomyces cerevisiae, with 515 residues per subunit, has been determined and refined to 2.4 A resolution. The crystallographic agreement factors R and Rfree are 15.4% and 19.8%, respectively. A tetramer with accurate 222-molecular symmetry is located in the asymmetric unit of the crystal. The conformation of the central core of catalase A, about 300 residues, remains similar to the structure of catalases from distantly related organisms. In contrast, catalase A lacks a carboxy-terminal domain equivalent to that found in catalase from Penicillium vitalae, the only other fungal catalase structure available. Structural peculiarities related with the heme and NADP(H) binding pockets can be correlated with biochemical characteristics of the catalase A enzyme. The network of molecular cavities and channels, filled with solvent molecules, supports the existence of one major substrate entry and at least two possible alternative pathways to the heme active site. The structure of the variant protein Val111Ala, also determined by X-ray crystallography at 2.8 A resolution, shows a few, well-localized, differences with respect to the wild-type enzyme. These differences, that include the widening of the entry channel in its narrowest point, provide an explanation for both the increased peroxidatic activity and the reduced catalatic activity of this mutant. |
==About this Structure== | ==About this Structure== | ||
| - | 1A4E is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with AZI, SO4 and HEM as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Catalase Catalase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.6 1.11.1.6] Full crystallographic information is available from [http:// | + | 1A4E is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=AZI:'>AZI</scene>, <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Catalase Catalase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.11.1.6 1.11.1.6] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1A4E OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Mate, M | + | [[Category: Mate, M J.]] |
[[Category: AZI]] | [[Category: AZI]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: peroxidase]] | [[Category: peroxidase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:40:44 2008'' |
Revision as of 09:40, 21 February 2008
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CATALASE A FROM SACCHAROMYCES CEREVISIAE
Overview
The structure of the peroxisomal catalase A from the budding yeast Saccharomyces cerevisiae, with 515 residues per subunit, has been determined and refined to 2.4 A resolution. The crystallographic agreement factors R and Rfree are 15.4% and 19.8%, respectively. A tetramer with accurate 222-molecular symmetry is located in the asymmetric unit of the crystal. The conformation of the central core of catalase A, about 300 residues, remains similar to the structure of catalases from distantly related organisms. In contrast, catalase A lacks a carboxy-terminal domain equivalent to that found in catalase from Penicillium vitalae, the only other fungal catalase structure available. Structural peculiarities related with the heme and NADP(H) binding pockets can be correlated with biochemical characteristics of the catalase A enzyme. The network of molecular cavities and channels, filled with solvent molecules, supports the existence of one major substrate entry and at least two possible alternative pathways to the heme active site. The structure of the variant protein Val111Ala, also determined by X-ray crystallography at 2.8 A resolution, shows a few, well-localized, differences with respect to the wild-type enzyme. These differences, that include the widening of the entry channel in its narrowest point, provide an explanation for both the increased peroxidatic activity and the reduced catalatic activity of this mutant.
About this Structure
1A4E is a Single protein structure of sequence from Saccharomyces cerevisiae with , and as ligands. Active as Catalase, with EC number 1.11.1.6 Full crystallographic information is available from OCA.
Reference
Structure of catalase-A from Saccharomyces cerevisiae., Mate MJ, Zamocky M, Nykyri LM, Herzog C, Alzari PM, Betzel C, Koller F, Fita I, J Mol Biol. 1999 Feb 12;286(1):135-49. PMID:9931255
Page seeded by OCA on Thu Feb 21 11:40:44 2008
Categories: Catalase | Saccharomyces cerevisiae | Single protein | Mate, M J. | AZI | HEM | SO4 | Oxidoreductase | Peroxidase
