2rb9
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Hydrogenases are enzymes involved in hydrogen metabolism, utilizing H2 as | + | Hydrogenases are enzymes involved in hydrogen metabolism, utilizing H2 as an electron source. [NiFe] hydrogenases are heterodimeric Fe-S proteins, with a large subunit containing the reaction center involving Fe and Ni metal ions and a small subunit containing one or more Fe-S clusters. Maturation of the [NiFe] hydrogenase involves assembly of nonproteinaceous ligands on the large subunit by accessory proteins encoded by the hyp operon. HypE is an essential accessory protein and participates in the synthesis of two cyano groups found in the large subunit. We report the crystal structure of Escherichia coli HypE at 2.0-A resolution. HypE exhibits a fold similar to that of PurM and ThiL and forms dimers. The C-terminal catalytically essential Cys336 is internalized at the dimer interface between the N- and C-terminal domains. A mechanism for dehydration of the thiocarbamate to the thiocyanate is proposed, involving Asp83 and Glu272. The interactions of HypE and HypF were characterized in detail by surface plasmon resonance and isothermal titration calorimetry, revealing a Kd (dissociation constant) of approximately 400 nM. The stoichiometry and molecular weights of the complex were verified by size exclusion chromatography and gel scanning densitometry. These experiments reveal that HypE and HypF associate to form a stoichiometric, hetero-oligomeric complex predominantly consisting of a [EF]2 heterotetramer which exists in a dynamic equilibrium with the EF heterodimer. The surface plasmon resonance results indicate that a conformational change occurs upon heterodimerization which facilitates formation of a productive complex as part of the carbamate transfer reaction. |
==About this Structure== | ==About this Structure== | ||
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==Reference== | ==Reference== | ||
| - | Structure of [NiFe] | + | Structure of [NiFe] hydrogenase maturation protein HypE from Escherichia coli and its interaction with HypF., Rangarajan ES, Asinas A, Proteau A, Munger C, Baardsnes J, Iannuzzi P, Matte A, Cygler M, J Bacteriol. 2008 Feb;190(4):1447-58. Epub 2007 Dec 7. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=18065529 18065529] |
[[Category: Escherichia coli o157:h7]] | [[Category: Escherichia coli o157:h7]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Asinas, A | + | [[Category: Asinas, A E.]] |
| - | [[Category: BSGI, Montreal-Kingston | + | [[Category: BSGI, Montreal-Kingston Bacterial Structural Genomics Initiative.]] |
[[Category: Cygler, M.]] | [[Category: Cygler, M.]] | ||
[[Category: Matte, A.]] | [[Category: Matte, A.]] | ||
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[[Category: Munger, C.]] | [[Category: Munger, C.]] | ||
[[Category: Proteau, A.]] | [[Category: Proteau, A.]] | ||
| - | [[Category: Rangarajan, E | + | [[Category: Rangarajan, E S.]] |
[[Category: bsgi]] | [[Category: bsgi]] | ||
[[Category: crystal structure]] | [[Category: crystal structure]] | ||
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[[Category: x-ray crystallography]] | [[Category: x-ray crystallography]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:46:03 2008'' |
Revision as of 16:46, 21 February 2008
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Crystal structure of E.coli HypE
Overview
Hydrogenases are enzymes involved in hydrogen metabolism, utilizing H2 as an electron source. [NiFe] hydrogenases are heterodimeric Fe-S proteins, with a large subunit containing the reaction center involving Fe and Ni metal ions and a small subunit containing one or more Fe-S clusters. Maturation of the [NiFe] hydrogenase involves assembly of nonproteinaceous ligands on the large subunit by accessory proteins encoded by the hyp operon. HypE is an essential accessory protein and participates in the synthesis of two cyano groups found in the large subunit. We report the crystal structure of Escherichia coli HypE at 2.0-A resolution. HypE exhibits a fold similar to that of PurM and ThiL and forms dimers. The C-terminal catalytically essential Cys336 is internalized at the dimer interface between the N- and C-terminal domains. A mechanism for dehydration of the thiocarbamate to the thiocyanate is proposed, involving Asp83 and Glu272. The interactions of HypE and HypF were characterized in detail by surface plasmon resonance and isothermal titration calorimetry, revealing a Kd (dissociation constant) of approximately 400 nM. The stoichiometry and molecular weights of the complex were verified by size exclusion chromatography and gel scanning densitometry. These experiments reveal that HypE and HypF associate to form a stoichiometric, hetero-oligomeric complex predominantly consisting of a [EF]2 heterotetramer which exists in a dynamic equilibrium with the EF heterodimer. The surface plasmon resonance results indicate that a conformational change occurs upon heterodimerization which facilitates formation of a productive complex as part of the carbamate transfer reaction.
About this Structure
2RB9 is a Single protein structure of sequence from Escherichia coli o157:h7. Full crystallographic information is available from OCA.
Reference
Structure of [NiFe] hydrogenase maturation protein HypE from Escherichia coli and its interaction with HypF., Rangarajan ES, Asinas A, Proteau A, Munger C, Baardsnes J, Iannuzzi P, Matte A, Cygler M, J Bacteriol. 2008 Feb;190(4):1447-58. Epub 2007 Dec 7. PMID:18065529
Page seeded by OCA on Thu Feb 21 18:46:03 2008
Categories: Escherichia coli o157:h7 | Single protein | Asinas, A E. | BSGI, Montreal-Kingston Bacterial Structural Genomics Initiative. | Cygler, M. | Matte, A. | Min, T. | Munger, C. | Proteau, A. | Rangarajan, E S. | Bsgi | Crystal structure | Dimer | Enzyme | Hydrogenase maturation | Montreal-kingston bacterial structural genomics initiative | Structural genomics | Unknown function | X-ray crystallography
