1gjr
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FERREDOXIN-NADP+ REDUCTASE COMPLEXED WITH NADP+ BY COCRYSTALLIZATION
OverviewOverview
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 StructureAbout this Structure
1GJR is a Single protein structure of sequence from Anabaena sp. with FAD and NAP as ligands. Active as Ferredoxin--NADP(+) reductase, with EC number 1.18.1.2 Structure known Active Site: FAD. Full crystallographic information is available from OCA.
ReferenceReference
Mechanism of coenzyme recognition and binding revealed by crystal structure analysis of ferredoxin-NADP+ reductase complexed with NADP+., Hermoso JA, Mayoral T, Faro M, Gomez-Moreno C, Sanz-Aparicio J, Medina M, J Mol Biol. 2002 Jun 21;319(5):1133-42. PMID:12079352
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