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1g21
From Proteopedia
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|PDB= 1g21 |SIZE=350|CAPTION= <scene name='initialview01'>1g21</scene>, resolution 3.0Å | |PDB= 1g21 |SIZE=350|CAPTION= <scene name='initialview01'>1g21</scene>, resolution 3.0Å | ||
|SITE= | |SITE= | ||
| - | |LIGAND= <scene name='pdbligand= | + | |LIGAND= <scene name='pdbligand=ATP:ADENOSINE-5'-TRIPHOSPHATE'>ATP</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CFM:FE-MO-S+CLUSTER'>CFM</scene>, <scene name='pdbligand=CLF:FE(8)-S(7)+CLUSTER'>CLF</scene>, <scene name='pdbligand=HCA:3-HYDROXY-3-CARBOXY-ADIPIC+ACID'>HCA</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=SF4:IRON/SULFUR+CLUSTER'>SF4</scene> |
| - | |ACTIVITY= [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] | + | |ACTIVITY= <span class='plainlinks'>[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] </span> |
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1g20|1G20]], [[1n2c|1n2c]], [[2min|2min]], [[3min|3min]], [[2nip|2nip]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1g21 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1g21 OCA], [http://www.ebi.ac.uk/pdbsum/1g21 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1g21 RCSB]</span> | ||
}} | }} | ||
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[[Category: Ryle, M J.]] | [[Category: Ryle, M J.]] | ||
[[Category: Seefeldt, L C.]] | [[Category: Seefeldt, L C.]] | ||
| - | [[Category: ATP]] | ||
| - | [[Category: CA]] | ||
| - | [[Category: CFM]] | ||
| - | [[Category: CLF]] | ||
| - | [[Category: HCA]] | ||
| - | [[Category: MG]] | ||
| - | [[Category: SF4]] | ||
[[Category: 4fe-4]] | [[Category: 4fe-4]] | ||
[[Category: fe protein]] | [[Category: fe protein]] | ||
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[[Category: p-cluster]] | [[Category: p-cluster]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 20:34:54 2008'' |
Revision as of 17:34, 30 March 2008
| |||||||
| , resolution 3.0Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , , , , , , | ||||||
| Activity: | Nitrogenase, with EC number 1.18.6.1 | ||||||
| Related: | 1G20, 1n2c, 2min, 3min, 2nip
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
MGATP-BOUND AND NUCLEOTIDE-FREE STRUCTURES OF A NITROGENASE PROTEIN COMPLEX BETWEEN LEU127DEL-FE PROTEIN AND THE MOFE PROTEIN
Overview
A mutant form of the nitrogenase iron protein with a deletion of residue Leu 127, located in the switch II region of the nucleotide binding site, forms a tight, inactive complex with the nitrogenase molybdenum iron (MoFe) protein in the absence of nucleotide. The structure of this complex generated with proteins from Azotobacter vinelandii (designated the L127Delta-Av2-Av1 complex) has been crystallographically determined in the absence of nucleotide at 2.2 A resolution and with bound MgATP (introduced by soaking) at 3.0 A resolution. As observed in the structure of the complex between the wild-type A. vinelandii nitrogenase proteins stabilized with ADP.AlF(4-), the most significant conformational changes in the L127Delta complex occur in the Fe-protein component. While the interactions at the interface between the MoFe-protein and Fe-proteins are conserved in the two complexes, significant differences are evident at the subunit-subunit interface of the dimeric Fe-proteins, with the L127Delta-Av2 structure having a more open conformation than the wild-type Av2 in the complex stabilized by ADP.AlF(4-). Addition of MgATP to the L127Delta-Av2-Av1 complex results in a further increase in the separation between Fe-protein subunits so that the structure more closely resembles that of the wild-type, nucleotide-free, uncomplexed Fe-protein, rather than the Fe-protein conformation in the ADP.AlF(4-) complex. The L127Delta mutation precludes key interactions between the Fe-protein and nucleotide, especially, but not exclusively, in the region corresponding to the switch II region of G-proteins, where the deletion constrains Gly 128 and Asp 129 from forming hydrogen bonds to the gamma-phosphate and activating water for attack on this group, respectively. These alterations account for the inability of this mutant to support mechanistically productive ATP hydrolysis. The ability of the L127Delta-Av2-Av1 complex to bind MgATP demonstrates that dissociation of the nitrogenase complex is not required for nucleotide binding.
About this Structure
1G21 is a Protein complex structure of sequences from Azotobacter vinelandii. Full crystallographic information is available from OCA.
Reference
MgATP-Bound and nucleotide-free structures of a nitrogenase protein complex between the Leu 127 Delta-Fe-protein and the MoFe-protein., Chiu H, Peters JW, Lanzilotta WN, Ryle MJ, Seefeldt LC, Howard JB, Rees DC, Biochemistry. 2001 Jan 23;40(3):641-50. PMID:11170380
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