1rw4
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(New page: 200px<br /><applet load="1rw4" size="450" color="white" frame="true" align="right" spinBox="true" caption="1rw4, resolution 2.5Å" /> '''Nitrogenase Fe protei...)
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Revision as of 23:46, 20 November 2007
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Nitrogenase Fe protein l127 deletion variant
Overview
The crystal structure of a nitrogenase Fe protein single site deletion, variant reveals a distinctly new conformation of the Fe protein and, indicates that, upon binding of MgATP, the Fe protein undergoes a dramatic, conformational change that is largely manifested in the rigid-body, reorientation of the homodimeric Fe protein subunits with respect to one, another. The observed conformational state allows the rationalization of a, model of structurally and chemically complementary interactions that occur, upon initial complex formation with the MoFe protein component that are, distinct from the protein-protein interactions that have been, characterized previously for stabilized nitrogenase complexes. The, crystallographic results, in combination with complementary UV-visible, absorption, EPR, and resonance Raman spectroscopic data, indicate that the, [4Fe-4S] cluster of both the Fe protein deletion variant and the native Fe, protein in the presence of MgATP can reversibly cycle between a regular, cubane-type [4Fe-4S] cluster in the reduced state and a cleaved form, involving two [2Fe-2S] fragments in the oxidized state. Resonance Raman, studies indicate that this novel cluster conversion is induced by, glycerol, and the crystallographic data suggest that glycerol is bound as, a bridging bidentate ligand to both [2Fe-2S] cluster fragments in the, oxidized state.
About this Structure
1RW4 is a Single protein structure of sequence from Azotobacter vinelandii with SF4 and GOL as ligands. Active as Nitrogenase, with EC number 1.18.6.1 Full crystallographic information is available from OCA.
Reference
A conformational mimic of the MgATP-bound "on state" of the nitrogenase iron protein., Sen S, Igarashi R, Smith A, Johnson MK, Seefeldt LC, Peters JW, Biochemistry. 2004 Feb 24;43(7):1787-97. PMID:14967020
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