2V5U

I92A FLAVODOXIN FROM ANABAENA

Summary for 2V5U

• Entry DOI: 10.2210/pdb2v5u/pdb
• Related: 1DX9 1FTG 1OBO 1OBV 1QHE 2V5V
• Descriptor: FLAVODOXIN, FLAVIN MONONUCLEOTIDE (3 entities in total)
• Functional Keywords: fmn, transport, flavoprotein, electron transfer, electron transport
• Biological source: ANABAENA SP.
• Total number of polymer chains: 2
• Total formula weight: 38491.59

Authors

Martinez-Julvez, M.,Herguedas, B.,Frago, S.,Serrano, A.,Molina, R.,Hamiaux, C.,Schierbeek, B.,Medina, M.,Hermoso, J.A. (deposition date: 2007-07-10, release date: 2007-10-16, Last modification date: 2023-12-13)

Primary citation

Frago, S.,Goni, G.,Herguedas, B.,Peregrina, J.R.,Serrano, A.,Perez-Dorado, I.,Molina, R.,Gomez-Moreno, C.,Hermoso, J.A.,Martinez-Julvez, M.,Mayhew, S.G.,Medina, M.
Tuning of the Fmn Binding and Oxido-Reduction Properties by Neighboring Side Chains in Anabaena Flavodoxin.
Arch.Biochem.Biophys., 467:206-, 2007

PubMed Abstract: Contribution of three regions (phosphate-binding, 50's and 90's loops) of Anabaena apoflavodoxin to FMN binding and reduction potential was studied. Thr12 and Glu16 did not influence FMN redox properties, but Thr12 played a role in FMN binding. Replacement of Trp57 with Glu, Lys or Arg moderately shifted E(ox/sq) and E(sq/hq) and altered the energetic of the FMN redox states binding profile. Our data indicate that the side chain of position 57 does not modulate E(ox/sq) by aromatic stacking or solvent exclusion, but rather by influencing the relative strength of the H-bond between the N(5) of the flavin and the Asn58-Ile59 bond. A correlation was observed between the isoalloxazine increase in solvent accessibility and less negative E(sq/hq). Moreover, E(sq/hq) became less negative as positively charged residues were added near to the isoalloxazine. Ile59 and Ile92 were simultaneously mutated to Ala or Glu. These mutations impaired FMN binding, while shifting E(sq/hq) to less negative values and E(ox/sq) to more negative. These effects are discussed on the bases of the X-ray structures of some of the Fld mutants, suggesting that in Anabaena Fld the structural control of both electron transfer steps is much more subtle than in other Flds.

PubMed: 17904516
DOI: 10.1016/J.ABB.2007.08.024

Experimental method

X-RAY DIFFRACTION (1.99 Å)