PDBsum entry 1go2

Oxidoreductase

PDB id: 1go2

Contents

Protein chain

295 a.a. *

Ligands

FAD

SO4

Waters ×306

* Residue conservation analysis

PDB id:

1go2

Name:

Oxidoreductase

Title:

Structure of ferredoxin-NADP+ reductase with lys 72 replaced by glu (k72e)

Structure:

Ferredoxin--NADP+ reductase. Chain: a. Fragment: residues 137-440. Synonym: fnr. Engineered: yes. Mutation: yes

Source:

Nostoc sp.. Organism_taxid: 1168. Strain: pcc 7119. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

1.70Å R-factor: 0.220 R-free: 0.250

Authors:

J.A.Hermoso,T.Mayoral,M.Medina,J.Sanz-Aparicio,C.Gomez-Moreno

Key ref:

T.Mayoral et al. (2005). Structural analysis of interactions for complex formation between Ferredoxin-NADP+ reductase and its protein partners. Proteins, 59, 592-602. PubMed id: 15789405 DOI: 10.1002/prot.20450

Date:

15-Oct-01 Release date: 17-Oct-02

Protein chain

P21890  (FENR_NOSSO) -  Ferredoxin--NADP reductase from Nostoc sp. (strain ATCC 29151 / PCC 7119)

Seq: 440 a.a.

Struc: 295 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

Enzyme reactions

• Enzyme class: E.C.1.18.1.2 - ferredoxin--NADP(+) reductase.
• Pathway: Methionine Synthase
• Reaction: 2 reduced [2Fe-2S]-[ferredoxin] + NADP⁺ + H⁺ = 2 oxidized [2Fe-2S]- [ferredoxin] + NADPH
• Cofactor: FAD

FAD (Bound ligand (Het Group name = FAD) corresponds exactly)

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

reference

DOI no: 10.1002/prot.20450

Proteins 59:592-602 (2005)

PubMed id: 15789405

Structural analysis of interactions for complex formation between Ferredoxin-NADP+ reductase and its protein partners.

T.Mayoral, M.Martínez-Júlvez, I.Pérez-Dorado, J.Sanz-Aparicio, C.Gómez-Moreno, M.Medina, J.A.Hermoso.

ABSTRACT

The three-dimensional structures of K72E, K75R, K75S, K75Q, and K75E Anabaena Ferredoxin-NADP+ reductase (FNR) mutants have been solved, and particular structural details of these mutants have been used to assess the role played by residues 72 and 75 in optimal complex formation and electron transfer (ET) between FNR and its protein redox partners Ferredoxin (Fd) and Flavodoxin (Fld). Additionally, because there is no structural information available on the interaction between FNR and Fld, a model for the FNR:Fld complex has also been produced based on the previously reported crystal structures and on that of the rat Cytochrome P450 reductase (CPR), onto which FNR and Fld have been structurally aligned, and those reported for the Anabaena and maize FNR:Fd complexes. The model suggests putative electrostatic and hydrophobic interactions between residues on the FNR and Fld surfaces at the complex interface and provides an adequate orientation and distance between the FAD and FMN redox centers for efficient ET without the presence of any other molecule as electron carrier. Thus, the models now available for the FNR:Fd and FNR:Fld interactions and the structures presented here for the mutants at K72 and K75 in Anabaena FNR have been evaluated in light of previous biochemical data. These structures confirm the key participation of residue K75 and K72 in complex formation with both Fd and Fld. The drastic effect in FNR activity produced by replacement of K75 by Glu in the K75E FNR variant is explained not only by the observed changes in the charge distribution on the surface of the K75E FNR mutant, but also by the formation of a salt bridge interaction between E75 and K72 that simultaneously "neutralizes" two essential positive charged side chains for Fld/Fd recognition.

Selected figure(s)

Figure 1.
Figure 1. Molecular surface showing the electrostatic potentials of (A) WT FNR and (B) WT Fld. Positive charges are shown in blue and negative ones in red. The FAD and FMN cofactors are represented as sticks.

Figure 5.
Figure 5. (A) Putative FNR:Fld complex showing the relative position of FAD and FMN cofactors, (B) charged residues at the FNR:Fld interface. (C) Hydrophobic residues on FNR and Fld in the putative complex. In all representations, Fld is colored in yellow and FNR in blue. (D) Crystal structure of FNR:Fd complex (PDB code 1EWY) showing the relative position of the redox centers. (E) Charged residues at the FNR:Fd interface. (F) Hydrophobic residues on FNR and Fd in the crystal structure of the complex.

The above figures are reprinted by permission from John Wiley & Sons, Inc.: Proteins (2005, 59, 592-602) copyright 2005.

Figures were selected by the author.