1wtf
From Proteopedia
(New page: 200px<br /><applet load="1wtf" size="450" color="white" frame="true" align="right" spinBox="true" caption="1wtf, resolution 1.60Å" /> '''Crystal structure of...) |
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| - | [[Image:1wtf.gif|left|200px]]<br /><applet load="1wtf" size=" | + | [[Image:1wtf.gif|left|200px]]<br /><applet load="1wtf" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1wtf, resolution 1.60Å" /> | caption="1wtf, resolution 1.60Å" /> | ||
'''Crystal structure of Bacillus thermoproteolyticus Ferredoxin Variants Containing Unexpected [3Fe-4S] Cluster that is linked to Coenzyme A at 1.6 A Resolution'''<br /> | '''Crystal structure of Bacillus thermoproteolyticus Ferredoxin Variants Containing Unexpected [3Fe-4S] Cluster that is linked to Coenzyme A at 1.6 A Resolution'''<br /> | ||
==Overview== | ==Overview== | ||
| - | During the purification of recombinant Bacillus thermoproteolyticus | + | During the purification of recombinant Bacillus thermoproteolyticus ferredoxin (BtFd) from Escherichia coli, we have noted that some Fe-S proteins were produced in relatively small amounts compared to the originally identified BtFd carrying a [4Fe-4S] cluster. These variants could be purified into three Fe-S protein components (designated as V-I, V-II, and V-III) by standard chromatography procedures. UV-vis and EPR spectroscopic analyses indicated that each of these variants accommodates a [3Fe-4S] cluster. From mass spectrometric and protein sequence analyses together with native and SDS gel electrophoresis, we established that V-I and V-II contain the polypeptide of BtFd associated with acyl carrier protein (ACP) and with coenzyme A (CoA), respectively, and that V-III is a BtFd dimer linked by a disulfide bond. The crystal structure of the BtFd-CoA complex (V-II) determined at 1.6 A resolution revealed that each of the four complexes in the crystallographic asymmetric unit possesses a [3Fe-4S] cluster that is coordinated by Cys(11), Cys(17), and Cys(61). The polypeptide chain of each complex is superimposable onto that of the original [4Fe-4S] BtFd except for the segment containing Cys(14), the fourth ligand to the [4Fe-4S] cluster of BtFd. In the variant molecules, the side chain of Cys(14) is rotated away to the molecular surface, forming a disulfide bond with the terminal sulfhydryl group of CoA. This covalent modification may have occurred in vivo, thereby preventing the assembly of the [4Fe-4S] cluster as observed previously for Desulfovibrio gigas ferredoxin. Possibilities concerning how the variant molecules are formed in the cell are discussed. |
==About this Structure== | ==About this Structure== | ||
| - | 1WTF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_thermoproteolyticus Bacillus thermoproteolyticus] with SO4, COA and F3S as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1WTF is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Bacillus_thermoproteolyticus Bacillus thermoproteolyticus] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=COA:'>COA</scene> and <scene name='pdbligand=F3S:'>F3S</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1WTF OCA]. |
==Reference== | ==Reference== | ||
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[[Category: ferredoxin]] | [[Category: ferredoxin]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:47:56 2008'' |
Revision as of 13:47, 21 February 2008
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Crystal structure of Bacillus thermoproteolyticus Ferredoxin Variants Containing Unexpected [3Fe-4S] Cluster that is linked to Coenzyme A at 1.6 A Resolution
Overview
During the purification of recombinant Bacillus thermoproteolyticus ferredoxin (BtFd) from Escherichia coli, we have noted that some Fe-S proteins were produced in relatively small amounts compared to the originally identified BtFd carrying a [4Fe-4S] cluster. These variants could be purified into three Fe-S protein components (designated as V-I, V-II, and V-III) by standard chromatography procedures. UV-vis and EPR spectroscopic analyses indicated that each of these variants accommodates a [3Fe-4S] cluster. From mass spectrometric and protein sequence analyses together with native and SDS gel electrophoresis, we established that V-I and V-II contain the polypeptide of BtFd associated with acyl carrier protein (ACP) and with coenzyme A (CoA), respectively, and that V-III is a BtFd dimer linked by a disulfide bond. The crystal structure of the BtFd-CoA complex (V-II) determined at 1.6 A resolution revealed that each of the four complexes in the crystallographic asymmetric unit possesses a [3Fe-4S] cluster that is coordinated by Cys(11), Cys(17), and Cys(61). The polypeptide chain of each complex is superimposable onto that of the original [4Fe-4S] BtFd except for the segment containing Cys(14), the fourth ligand to the [4Fe-4S] cluster of BtFd. In the variant molecules, the side chain of Cys(14) is rotated away to the molecular surface, forming a disulfide bond with the terminal sulfhydryl group of CoA. This covalent modification may have occurred in vivo, thereby preventing the assembly of the [4Fe-4S] cluster as observed previously for Desulfovibrio gigas ferredoxin. Possibilities concerning how the variant molecules are formed in the cell are discussed.
About this Structure
1WTF is a Single protein structure of sequence from Bacillus thermoproteolyticus with , and as ligands. Full crystallographic information is available from OCA.
Reference
Identification of variant molecules of Bacillus thermoproteolyticus ferredoxin: crystal structure reveals bound coenzyme A and an unexpected [3Fe-4S] cluster associated with a canonical [4Fe-4S] ligand motif., Shirakawa T, Takahashi Y, Wada K, Hirota J, Takao T, Ohmori D, Fukuyama K, Biochemistry. 2005 Sep 20;44(37):12402-10. PMID:16156653
Page seeded by OCA on Thu Feb 21 15:47:56 2008
Categories: Bacillus thermoproteolyticus | Single protein | Fukuyama, K. | Hirota, J. | Ohmori, D. | Shirakawa, T. | Takahashi, Y. | Takao, T. | Wada, K. | COA | F3S | SO4 | 3fe-4s cluster | Coenzyme a | Complex | Ferredoxin
