1gjr: Difference between revisions
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==Overview== | ==Overview== | ||
The flavoenzyme ferredoxin-NADP+ reductase (FNR) catalyses the production, of NADPH in photosynthesis. The three-dimensional structure of FNR, presents two distinct domains, one for binding of the FAD prosthetic group, and the other for NADP+ binding. In spite of extensive experiments and, different crystallographic approaches, many aspects about how the NADP+, substrate binds to FNR and how the hydride ion is transferred from FAD to, NADP+ remain unclear. The structure of an FNR:NADP+ complex from Anabaena, has been determined by X-ray diffraction analysis of the cocrystallised, units to 2.1 A resolution. Structural perturbation of FNR induced by, complex formation produces a narrower cavity in which the 2'-phospho-AMP, and pyrophosphate portions of the NADP+ are perfectly bound. In ... | The flavoenzyme ferredoxin-NADP+ reductase (FNR) catalyses the production, of NADPH in photosynthesis. The three-dimensional structure of FNR, presents two distinct domains, one for binding of the FAD prosthetic group, and the other for NADP+ binding. In spite of extensive experiments and, different crystallographic approaches, many aspects about how the NADP+, substrate binds to FNR and how the hydride ion is transferred from FAD to, NADP+ remain unclear. The structure of an FNR:NADP+ complex from Anabaena, has been determined by X-ray diffraction analysis of the cocrystallised, units to 2.1 A resolution. Structural perturbation of FNR induced by, complex formation produces a narrower cavity in which the 2'-phospho-AMP, and pyrophosphate portions of the NADP+ are perfectly bound. In addition, the nicotinamide mononucleotide moiety is placed in a new pocket created, near the FAD cofactor with the ribose being in a tight conformation. The, crystal structure of this FNR:NADP+ complex obtained by cocrystallisation, displays NADP+ in an unusual conformation and can be considered as an, intermediate state in the process of coenzyme recognition and binding., Structural analysis and comparison with previously reported complexes, allow us to postulate a mechanism which would permit efficient hydride, transfer to occur. Besides, this structure gives new insights into the, postulated formation of the ferredoxin:FNR:NADP+ ternary complex by, prediction of new intermolecular interactions, which could only exist, after FNR:NADP+ complex formation. Finally, structural comparison with the, members of the broad FNR structural family also provides an explanation, for the high specificity exhibited by FNR for NADP+/H versus NAD+/H. | ||
==About this Structure== | ==About this Structure== | ||
1GJR is a | 1GJR is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Anabaena_sp. Anabaena sp.] with FAD and NAP as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Ferredoxin--NADP(+)_reductase Ferredoxin--NADP(+) reductase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.18.1.2 1.18.1.2] Structure known Active Site: FAD. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1GJR OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:41:34 2007'' | ||
