3ZBT

Ferredoxin-NADP Reductase Mutant with SER 59 Replaced by ALA (S59A)

Summary for 3ZBT

• Entry DOI: 10.2210/pdb3zbt/pdb
• Related: 3ZBU 3ZC3
• Descriptor: FERREDOXIN-NADP REDUCTASE, FLAVIN-ADENINE DINUCLEOTIDE, SULFATE ION, ... (5 entities in total)
• Functional Keywords: oxidoreductase, flavoprotein
• Biological source: NOSTOC SP. PCC7119
• Cellular location: Cellular thylakoid membrane; Peripheral membrane protein; Cytoplasmic side: P21890
• Total number of polymer chains: 1
• Total formula weight: 35000.36

Authors

Martinez-Julvez, M.,Herguedas, B.,Sanchez-Azqueta, A.,Hervas, M.,Navarro, J.A.,Medina, M. (deposition date: 2012-11-13, release date: 2013-11-20, Last modification date: 2023-12-20)

Primary citation

Sanchez-Azqueta, A.,Herguedas, B.,Hurtado-Guerrero, R.,Hervas, M.,Navarro, J.A.,Martinez-Julvez, M.,Medina, M.
A Hydrogen Bond Network in the Active Site of Anabaena Ferredoxin-Nadp(+) Reductase Modulates its Catalytic Efficiency.
Biochim.Biophys.Acta, 1837:251-, 2013

PubMed Abstract: Ferredoxin-nicotinamide-adenine dinucleotide phosphate (NADP(+)) reductase (FNR) catalyses the production of reduced nicotinamide-adenine dinucleotide phosphate (NADPH) in photosynthetic organisms, where its flavin adenine dinucleotide (FAD) cofactor takes two electrons from two reduced ferredoxin (Fd) molecules in two sequential steps, and transfers them to NADP(+) in a single hydride transfer (HT) step. Despite the good knowledge of this catalytic machinery, additional roles can still be envisaged for already reported key residues, and new features are added to residues not previously identified as having a particular role in the mechanism. Here, we analyse for the first time the role of Ser59 in Anabaena FNR, a residue suggested by recent theoretical simulations as putatively involved in competent binding of the coenzyme in the active site by cooperating with Ser80. We show that Ser59 indirectly modulates the geometry of the active site, the interaction with substrates and the electronic properties of the isoalloxazine ring, and in consequence the electron transfer (ET) and HT processes. Additionally, we revise the role of Tyr79 and Ser80, previously investigated in homologous enzymes from plants. Our results probe that the active site of FNR is tuned by a H-bond network that involves the side-chains of these residues and that results to critical optimal substrate binding, exchange of electrons and, particularly, competent disposition of the C4n (hydride acceptor/donor) of the nicotinamide moiety of the coenzyme during the reversible HT event.

PubMed: 24200908
DOI: 10.1016/J.BBABIO.2013.10.010

Experimental method

X-RAY DIFFRACTION (1.92 Å)