2v5v
From Proteopedia
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W57E FLAVODOXIN FROM ANABAENA
Overview
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.
About this Structure
2V5V is a Single protein structure of sequence from Anabaena sp. with and as ligands. Known structural/functional Sites: , and . Full crystallographic information is available from OCA.
Reference
Tuning of the FMN binding and oxido-reduction properties by neighboring side chains in Anabaena flavodoxin., Frago S, Goni G, Herguedas B, Peregrina JR, Serrano A, Perez-Dorado I, Molina R, Gomez-Moreno C, Hermoso JA, Martinez-Julvez M, Mayhew SG, Medina M, Arch Biochem Biophys. 2007 Aug 29;. PMID:17904516
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