2flo
From Proteopedia
(New page: 200px<br /><applet load="2flo" size="450" color="white" frame="true" align="right" spinBox="true" caption="2flo, resolution 2.20Å" /> '''Crystal structure of...) |
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| - | [[Image:2flo.gif|left|200px]]<br /><applet load="2flo" size=" | + | [[Image:2flo.gif|left|200px]]<br /><applet load="2flo" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2flo, resolution 2.20Å" /> | caption="2flo, resolution 2.20Å" /> | ||
'''Crystal structure of exopolyphosphatase (PPX) from E. coli O157:H7'''<br /> | '''Crystal structure of exopolyphosphatase (PPX) from E. coli O157:H7'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Polyphosphate (polyP) is a linear polymer consisting of tens to hundreds | + | Polyphosphate (polyP) is a linear polymer consisting of tens to hundreds of phosphate molecules joined together by high-energy anhydride bonds. These polymers are found in virtually all prokaryotic and eukaryotic cells and perform many functions; prominent among them are the responses to many stresses. Polyphosphate is synthesized by polyP kinase (PPK), using the terminal phosphate of ATP as the substrate, and degraded to inorganic phosphate by both endo- and exopolyphosphatases. Here we report the crystal structure and analysis of the polyphosphate phosphatase PPX from Escherichia coli O157:H7 refined at 2.2 Angstroms resolution. PPX is made of four domains. Domains I and II display structural similarity with one another and share the ribonuclease-H-like fold. Domain III bears structural similarity to the N-terminal, HD domain of SpoT. Domain IV, the smallest domain, has structural counterparts in cold-shock associated RNA-binding proteins but is of unknown function in PPX. The putative PPX active site is located at the interface between domains I and II. In the crystal structure of PPX these two domains are close together and represent the "closed" state. Comparison with the crystal structure of PPX/GPPA from Aquifex aeolicus reveals close structural similarity between domains I and II of the two enzymes, with the PPX/GPPA representing an "open" state. A striking feature of the dimer is a deep S-shaped canyon extending along the dimer interface and lined with positively charged residues. The active site region opens to this canyon. We postulate that this is a likely site of polyP binding. |
==About this Structure== | ==About this Structure== | ||
| - | 2FLO is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Active as [http://en.wikipedia.org/wiki/Exopolyphosphatase Exopolyphosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.1.11 3.6.1.11] Full crystallographic information is available from [http:// | + | 2FLO is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Active as [http://en.wikipedia.org/wiki/Exopolyphosphatase Exopolyphosphatase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.1.11 3.6.1.11] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2FLO OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Exopolyphosphatase]] | [[Category: Exopolyphosphatase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: BSGI, Montreal-Kingston | + | [[Category: BSGI, Montreal-Kingston Bacterial Structural Genomics Initiative.]] |
[[Category: Cygler, M.]] | [[Category: Cygler, M.]] | ||
[[Category: Matte, A.]] | [[Category: Matte, A.]] | ||
| - | [[Category: Rangarajan, E | + | [[Category: Rangarajan, E S.]] |
[[Category: bacterial structural genomics]] | [[Category: bacterial structural genomics]] | ||
[[Category: bsgi]] | [[Category: bsgi]] | ||
| Line 26: | Line 26: | ||
[[Category: structural genomics]] | [[Category: structural genomics]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:22:44 2008'' |
Revision as of 15:22, 21 February 2008
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Crystal structure of exopolyphosphatase (PPX) from E. coli O157:H7
Overview
Polyphosphate (polyP) is a linear polymer consisting of tens to hundreds of phosphate molecules joined together by high-energy anhydride bonds. These polymers are found in virtually all prokaryotic and eukaryotic cells and perform many functions; prominent among them are the responses to many stresses. Polyphosphate is synthesized by polyP kinase (PPK), using the terminal phosphate of ATP as the substrate, and degraded to inorganic phosphate by both endo- and exopolyphosphatases. Here we report the crystal structure and analysis of the polyphosphate phosphatase PPX from Escherichia coli O157:H7 refined at 2.2 Angstroms resolution. PPX is made of four domains. Domains I and II display structural similarity with one another and share the ribonuclease-H-like fold. Domain III bears structural similarity to the N-terminal, HD domain of SpoT. Domain IV, the smallest domain, has structural counterparts in cold-shock associated RNA-binding proteins but is of unknown function in PPX. The putative PPX active site is located at the interface between domains I and II. In the crystal structure of PPX these two domains are close together and represent the "closed" state. Comparison with the crystal structure of PPX/GPPA from Aquifex aeolicus reveals close structural similarity between domains I and II of the two enzymes, with the PPX/GPPA representing an "open" state. A striking feature of the dimer is a deep S-shaped canyon extending along the dimer interface and lined with positively charged residues. The active site region opens to this canyon. We postulate that this is a likely site of polyP binding.
About this Structure
2FLO is a Single protein structure of sequence from Escherichia coli. Active as Exopolyphosphatase, with EC number 3.6.1.11 Full crystallographic information is available from OCA.
Reference
The structure of the exopolyphosphatase (PPX) from Escherichia coli O157:H7 suggests a binding mode for long polyphosphate chains., Rangarajan ES, Nadeau G, Li Y, Wagner J, Hung MN, Schrag JD, Cygler M, Matte A, J Mol Biol. 2006 Jun 23;359(5):1249-60. Epub 2006 Apr 27. PMID:16678853
Page seeded by OCA on Thu Feb 21 17:22:44 2008
Categories: Escherichia coli | Exopolyphosphatase | Single protein | BSGI, Montreal-Kingston Bacterial Structural Genomics Initiative. | Cygler, M. | Matte, A. | Rangarajan, E S. | Bacterial structural genomics | Bsgi | Metaphosphatase | Montreal-kingston bacterial structural genomics initiative | Ppx/gppa | Structural genomics
