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1zlq
From Proteopedia
(New page: 200px<br /><applet load="1zlq" size="450" color="white" frame="true" align="right" spinBox="true" caption="1zlq, resolution 1.8Å" /> '''Crystallographic and ...) |
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| - | [[Image:1zlq.gif|left|200px]]<br /><applet load="1zlq" size=" | + | [[Image:1zlq.gif|left|200px]]<br /><applet load="1zlq" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1zlq, resolution 1.8Å" /> | caption="1zlq, resolution 1.8Å" /> | ||
'''Crystallographic and spectroscopic evidence for high affinity binding of Fe EDTA (H2O)- to the periplasmic nickel transporter NikA'''<br /> | '''Crystallographic and spectroscopic evidence for high affinity binding of Fe EDTA (H2O)- to the periplasmic nickel transporter NikA'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Because nickel is both essential and toxic to a great variety of | + | Because nickel is both essential and toxic to a great variety of organisms, its detection and transport is highly regulated. In Escherichia coli and other related Gram-negative bacteria, high affinity nickel transport depends on proteins expressed by the nik operon. A central actor of this process is the periplasmic NikA transport protein. A previous structural report has proposed that nickel binds to NikA as a pentahydrate species. However, both stereochemical considerations and X-ray absorption spectroscopic results are incompatible with that interpretation. Here, we report the 1.8 A resolution structure of NikA and show that it binds FeEDTA(H2O)- with very high affinity. In addition, we provide crystallographic evidence that a metal-EDTA complex was also bound to the previously reported NikA structure. Our observations strongly suggest that nickel transport in E. coli requires the binding of this metal ion to a metallophore that bears significant resemblance to EDTA. They also provide a basis for the potential use of NikA in the bioremediation of toxic transition metals and the design of artificial metalloenzymes. |
==About this Structure== | ==About this Structure== | ||
| - | 1ZLQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with FE, ACT, SO4, CL, EDT, DTT and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Nickel-transporting_ATPase Nickel-transporting ATPase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.3.24 3.6.3.24] Full crystallographic information is available from [http:// | + | 1ZLQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=FE:'>FE</scene>, <scene name='pdbligand=ACT:'>ACT</scene>, <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=EDT:'>EDT</scene>, <scene name='pdbligand=DTT:'>DTT</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Nickel-transporting_ATPase Nickel-transporting ATPase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.6.3.24 3.6.3.24] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ZLQ OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Nickel-transporting ATPase]] | [[Category: Nickel-transporting ATPase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Camps, J | + | [[Category: Camps, J C.Fontecilla.]] |
[[Category: Cavazza, C.]] | [[Category: Cavazza, C.]] | ||
| - | [[Category: Cherrier, M | + | [[Category: Cherrier, M V.]] |
[[Category: Gaillard, J.]] | [[Category: Gaillard, J.]] | ||
[[Category: Jacquamet, L.]] | [[Category: Jacquamet, L.]] | ||
| Line 34: | Line 34: | ||
[[Category: transport]] | [[Category: transport]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:16:49 2008'' |
Revision as of 14:16, 21 February 2008
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Crystallographic and spectroscopic evidence for high affinity binding of Fe EDTA (H2O)- to the periplasmic nickel transporter NikA
Overview
Because nickel is both essential and toxic to a great variety of organisms, its detection and transport is highly regulated. In Escherichia coli and other related Gram-negative bacteria, high affinity nickel transport depends on proteins expressed by the nik operon. A central actor of this process is the periplasmic NikA transport protein. A previous structural report has proposed that nickel binds to NikA as a pentahydrate species. However, both stereochemical considerations and X-ray absorption spectroscopic results are incompatible with that interpretation. Here, we report the 1.8 A resolution structure of NikA and show that it binds FeEDTA(H2O)- with very high affinity. In addition, we provide crystallographic evidence that a metal-EDTA complex was also bound to the previously reported NikA structure. Our observations strongly suggest that nickel transport in E. coli requires the binding of this metal ion to a metallophore that bears significant resemblance to EDTA. They also provide a basis for the potential use of NikA in the bioremediation of toxic transition metals and the design of artificial metalloenzymes.
About this Structure
1ZLQ is a Single protein structure of sequence from Escherichia coli with , , , , , and as ligands. Active as Nickel-transporting ATPase, with EC number 3.6.3.24 Full crystallographic information is available from OCA.
Reference
Crystallographic and spectroscopic evidence for high affinity binding of FeEDTA(H2O)- to the periplasmic nickel transporter NikA., Cherrier MV, Martin L, Cavazza C, Jacquamet L, Lemaire D, Gaillard J, Fontecilla-Camps JC, J Am Chem Soc. 2005 Jul 20;127(28):10075-82. PMID:16011372
Page seeded by OCA on Thu Feb 21 16:16:49 2008
Categories: Escherichia coli | Nickel-transporting ATPase | Single protein | Camps, J C.Fontecilla. | Cavazza, C. | Cherrier, M V. | Gaillard, J. | Jacquamet, L. | Lemaire, D. | Martin, L. | ACT | CL | DTT | EDT | FE | GOL | SO4 | Bacteria | Edta | Nickel | Periplasm | Transport
