1qh8
From Proteopedia
(New page: 200px<br /><applet load="1qh8" size="450" color="white" frame="true" align="right" spinBox="true" caption="1qh8, resolution 1.60Å" /> '''NITROGENASE MOFE PRO...) |
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| - | [[Image:1qh8.jpg|left|200px]]<br /><applet load="1qh8" size=" | + | [[Image:1qh8.jpg|left|200px]]<br /><applet load="1qh8" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1qh8, resolution 1.60Å" /> | caption="1qh8, resolution 1.60Å" /> | ||
'''NITROGENASE MOFE PROTEIN FROM KLEBSIELLA PNEUMONIAE, AS-CRYSTALLIZED (MIXED OXIDATION) STATE'''<br /> | '''NITROGENASE MOFE PROTEIN FROM KLEBSIELLA PNEUMONIAE, AS-CRYSTALLIZED (MIXED OXIDATION) STATE'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The X-ray crystal structure of Klebsiella pneumoniae nitrogenase component | + | The X-ray crystal structure of Klebsiella pneumoniae nitrogenase component 1 (Kp1) has been determined and refined to a resolution of 1.6 A, the highest resolution reported for any nitrogenase structure. Models derived from three 1.6 A resolution X-ray data sets are described; two represent distinct oxidation states, whilst the third appears to be a mixture of both oxidized and reduced states (or perhaps an intermediate state). The structures of the protein and the iron-molybdenum cofactor (FeMoco) appear to be largely unaffected by the redox status, although the movement of Ser beta90 and a surface helix in the beta subunit may be of functional significance. By contrast, the 8Fe-7S P-cluster undergoes discrete conformational changes involving the movement of two iron atoms. Comparisons with known component 1 structures reveal subtle differences in the FeMoco environment, which could account for the lower midpoint potential of this cluster in Kp1. Furthermore, a non-proline- cis peptide bond has been identified in the alpha subunit that may have a functional role. It is within 10 A of the FeMoco and may have been overlooked in other component 1 models. Finally, metal-metal and metal-sulphur distances within the metal clusters agree well with values derived from EXAFS studies, although they are generally longer than the values reported for the closely related protein from Azotobacter vinelandii. A number of bonds between the clusters and their ligands are distinctly longer than the EXAFS values, in particular, those involving the molybdenum atom of the FeMoco. |
==About this Structure== | ==About this Structure== | ||
| - | 1QH8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Klebsiella_pneumoniae Klebsiella pneumoniae] with CL, MG, HCA, CFM, CLF and EDO as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Nitrogenase Nitrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.18.6.1 1.18.6.1] Full crystallographic information is available from [http:// | + | 1QH8 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Klebsiella_pneumoniae Klebsiella pneumoniae] with <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=HCA:'>HCA</scene>, <scene name='pdbligand=CFM:'>CFM</scene>, <scene name='pdbligand=CLF:'>CLF</scene> and <scene name='pdbligand=EDO:'>EDO</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Nitrogenase Nitrogenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.18.6.1 1.18.6.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QH8 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Nitrogenase]] | [[Category: Nitrogenase]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Gormal, C | + | [[Category: Gormal, C A.]] |
| - | [[Category: Lawson, D | + | [[Category: Lawson, D M.]] |
| - | [[Category: Mayer, S | + | [[Category: Mayer, S M.]] |
| - | [[Category: Roe, S | + | [[Category: Roe, S M.]] |
| - | [[Category: Smith, B | + | [[Category: Smith, B E.]] |
[[Category: CFM]] | [[Category: CFM]] | ||
[[Category: CL]] | [[Category: CL]] | ||
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[[Category: nitrogen metabolism]] | [[Category: nitrogen metabolism]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:39:29 2008'' |
Revision as of 12:39, 21 February 2008
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NITROGENASE MOFE PROTEIN FROM KLEBSIELLA PNEUMONIAE, AS-CRYSTALLIZED (MIXED OXIDATION) STATE
Overview
The X-ray crystal structure of Klebsiella pneumoniae nitrogenase component 1 (Kp1) has been determined and refined to a resolution of 1.6 A, the highest resolution reported for any nitrogenase structure. Models derived from three 1.6 A resolution X-ray data sets are described; two represent distinct oxidation states, whilst the third appears to be a mixture of both oxidized and reduced states (or perhaps an intermediate state). The structures of the protein and the iron-molybdenum cofactor (FeMoco) appear to be largely unaffected by the redox status, although the movement of Ser beta90 and a surface helix in the beta subunit may be of functional significance. By contrast, the 8Fe-7S P-cluster undergoes discrete conformational changes involving the movement of two iron atoms. Comparisons with known component 1 structures reveal subtle differences in the FeMoco environment, which could account for the lower midpoint potential of this cluster in Kp1. Furthermore, a non-proline- cis peptide bond has been identified in the alpha subunit that may have a functional role. It is within 10 A of the FeMoco and may have been overlooked in other component 1 models. Finally, metal-metal and metal-sulphur distances within the metal clusters agree well with values derived from EXAFS studies, although they are generally longer than the values reported for the closely related protein from Azotobacter vinelandii. A number of bonds between the clusters and their ligands are distinctly longer than the EXAFS values, in particular, those involving the molybdenum atom of the FeMoco.
About this Structure
1QH8 is a Protein complex structure of sequences from Klebsiella pneumoniae with , , , , and as ligands. Active as Nitrogenase, with EC number 1.18.6.1 Full crystallographic information is available from OCA.
Reference
New insights into structure-function relationships in nitrogenase: A 1.6 A resolution X-ray crystallographic study of Klebsiella pneumoniae MoFe-protein., Mayer SM, Lawson DM, Gormal CA, Roe SM, Smith BE, J Mol Biol. 1999 Oct 1;292(4):871-91. PMID:10525412
Page seeded by OCA on Thu Feb 21 14:39:29 2008
Categories: Klebsiella pneumoniae | Nitrogenase | Protein complex | Gormal, C A. | Lawson, D M. | Mayer, S M. | Roe, S M. | Smith, B E. | CFM | CL | CLF | EDO | HCA | MG | Biological nitrogen fixation | Electron transfer | Molybdoenzymes | Nitrogen metabolism
