1j3b
From Proteopedia
(New page: 200px<br /><applet load="1j3b" size="450" color="white" frame="true" align="right" spinBox="true" caption="1j3b, resolution 2.0Å" /> '''Crystal structure of ...) |
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| - | [[Image:1j3b.jpg|left|200px]]<br /><applet load="1j3b" size=" | + | [[Image:1j3b.jpg|left|200px]]<br /><applet load="1j3b" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1j3b, resolution 2.0Å" /> | caption="1j3b, resolution 2.0Å" /> | ||
'''Crystal structure of ATP-dependent phosphoenolpyruvate carboxykinase from Thermus thermophilus HB8'''<br /> | '''Crystal structure of ATP-dependent phosphoenolpyruvate carboxykinase from Thermus thermophilus HB8'''<br /> | ||
==Overview== | ==Overview== | ||
| - | In order to understand the induced fit and the thermostabilization | + | In order to understand the induced fit and the thermostabilization mechanisms of ATP-dependent phosphoenolpyruvate carboxykinase, the crystal structure of the enzyme from the extreme thermophile Thermus thermophilus HB8 (TtPEPCK) was determined and compared with those of orthologues of known structure from two mesophilic organisms. The protomer structures in these orthologues, which exhibit open/closed interdomain conformations, are similar. Isomorphous crystals of unliganded and ATP-bound TtPEPCK were obtained. The asymmetric units of both crystal forms contain two protomers A and B with closed and open conformations, respectively. ATP was only observed in the interdomain cleft of the closed protomer, suggesting that the induced fit of TtPEPCK agrees with the so-called ;conformational selection' mechanism where ligand binding is not essential for domain closure although its binding leads to the stabilization of the closed state. A bound calcium observed in the N-terminal domain of TtPEPCK probably contributes to the thermal stability. A combination of hydrophobic effects, ion pairs and entropic effects might also contribute to the thermostability of TtPEPCK. |
==About this Structure== | ==About this Structure== | ||
| - | 1J3B is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with CA, PO4 and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1J3B is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with <scene name='pdbligand=CA:'>CA</scene>, <scene name='pdbligand=PO4:'>PO4</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=1J3B OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Kunishima, N.]] | [[Category: Kunishima, N.]] | ||
[[Category: Miyano, M.]] | [[Category: Miyano, M.]] | ||
| - | [[Category: RSGI, RIKEN | + | [[Category: RSGI, RIKEN Structural Genomics/Proteomics Initiative.]] |
[[Category: Sugahara, M.]] | [[Category: Sugahara, M.]] | ||
[[Category: CA]] | [[Category: CA]] | ||
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[[Category: thermus thermophilus]] | [[Category: thermus thermophilus]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:18:31 2008'' |
Revision as of 11:18, 21 February 2008
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Crystal structure of ATP-dependent phosphoenolpyruvate carboxykinase from Thermus thermophilus HB8
Overview
In order to understand the induced fit and the thermostabilization mechanisms of ATP-dependent phosphoenolpyruvate carboxykinase, the crystal structure of the enzyme from the extreme thermophile Thermus thermophilus HB8 (TtPEPCK) was determined and compared with those of orthologues of known structure from two mesophilic organisms. The protomer structures in these orthologues, which exhibit open/closed interdomain conformations, are similar. Isomorphous crystals of unliganded and ATP-bound TtPEPCK were obtained. The asymmetric units of both crystal forms contain two protomers A and B with closed and open conformations, respectively. ATP was only observed in the interdomain cleft of the closed protomer, suggesting that the induced fit of TtPEPCK agrees with the so-called ;conformational selection' mechanism where ligand binding is not essential for domain closure although its binding leads to the stabilization of the closed state. A bound calcium observed in the N-terminal domain of TtPEPCK probably contributes to the thermal stability. A combination of hydrophobic effects, ion pairs and entropic effects might also contribute to the thermostability of TtPEPCK.
About this Structure
1J3B is a Single protein structure of sequence from Thermus thermophilus with , and as ligands. Full crystallographic information is available from OCA.
Reference
Structure of ATP-dependent phosphoenolpyruvate carboxykinase from Thermus thermophilus HB8 showing the structural basis of induced fit and thermostability., Sugahara M, Ohshima N, Ukita Y, Sugahara M, Kunishima N, Acta Crystallogr D Biol Crystallogr. 2005 Nov;61(Pt 11):1500-7. Epub 2005, Oct 19. PMID:16239727
Page seeded by OCA on Thu Feb 21 13:18:31 2008
Categories: Single protein | Thermus thermophilus | Kunishima, N. | Miyano, M. | RSGI, RIKEN Structural Genomics/Proteomics Initiative. | Sugahara, M. | CA | GOL | PO4 | Adenosine triphosphate | Phosphoenolpyruvate carboxykinase | Riken structural genomics/proteomics initiative | Rsgi | Structural genomics
