Disease relevance of fpr

• Among them, the new genes mvrA and mvrB were mapped at 7 and 28 min on the E. coli linkage map, respectively [1].
• Resistance against MV toxicity could be restored by the introduction of cloned DNA sequences encoding pea chloroplast ferredoxin-NADP+ reductase (FNR), a member of a class of flavoenzymes involved in redox pathways in bacteria, plants and animals [2].

High impact information on fpr

• These data show that control of CYP activity in S. coelicolor A3(2) involves specific interactions with fpr and their availability during the life cycle and, after xenobiotic exposure, represents a unique mechanism for regulating CYP function [3].
• The FMN-binding domain is similar to the structure of flavodoxin, whereas the two C-terminal dinucleotide-binding domains are similar to those of ferredoxin-NADP+ reductase (FNR) [4].
• In that case, the fpr gene is known to be activated in response to oxidative stress [5].
• The identified palindrome is approximately 50% identical to the SoxS binding site upstream of Escherichia coli fpr, suggesting that A. vinelandii may have a SoxS-like regulatory system and that the function of FdI might be to specifically inactivate that system [6].
• A luciferase reporter gene was placed under control of the A. vinelandii fpr promoter and introduced into wild type and FdI- strains of A. vinelandii [6].

Chemical compound and disease context of fpr

• Escherichia coli ferredoxin NADP+ reductase: activation of E. coli anaerobic ribonucleotide reduction, cloning of the gene (fpr), and overexpression of the protein [7].
• Escherichia coli cells from strain fpr, deficient in the soxRS-induced ferredoxin (flavodoxin)-NADP(H) reductase (FPR), display abnormal sensitivity to the bactericidal effects of the superoxide-generating reagent methyl viologen (MV) [8].

Biological context of fpr

• The mvrA gene, which was predicted to range in size from 600 to 900 base pairs (bp) by transposon Tn1000 insertion analysis, was identified to be 807 bp, with an approximately 60-bp promoter sequence carrying consensus sequences for the -35 region, the -10 region, and a ribosome-binding site [1].
• We show that the cloned mvrA gene (M. Morimyo, J. Bacteriol. 170:2136-2142, 1988) originated from the 88-min region of the Escherichia coli chromosome and not, as reported, from the 7-min region and that the gene product identified as MvrA is in fact encoded by a gene distal to glpX [9].
• Complementation was strictly dependent on the accumulation of a functional transgenic FNR, since mutated reductases showing decreased enzymatic activities only partially rescued the MV-resistant phenotype [2].
• Supposing that opposite orientation of the SoxS binding site at the two promoters might account for the positional requirements, we placed the zwf and fpr soxboxes in the reverse orientation at the various positions upstream of the promoters and determined the effect of orientation on transcription activation [10].
• Accumulation of a site-directed FPR mutant that uses NAD(H) instead of NADP(H) had no effect on soxRS induction and failed to protect fpr cells from MV toxicity, suggesting that FPR contributes to NADP(H) homeostasis in stressed bacteria [8].

Associations of fpr with chemical compounds

• Steady-state kinetic parameters for these FNR mutants, utilizing the diaphorase activity with DCPIP, indicate that Lys75 is not a critical residue for complex formation and electron transfer (ET) between FNR and NADP+ or NADPH [11].
• The data presented here indicate that the mutated residues situated within the FNR FAD-binding domain are more important for achieving maximal ET rates, either with Fd or Fld, than those situated within the NADP(+)-binding domain, and that both ET proteins occupy the same region for the interaction with the reductase [12].
• Neither bacteriostatic effects nor inactivation of oxidant-sensitive hydrolyases could be detected in fpr cells exposed to MV [8].

Physical interactions of fpr

• The enzyme ferredoxin-NADP(+) reductase (FNR) forms a 1 : 1 complex with ferredoxin (Fd) or flavodoxin (Fld) that is stabilised by both electrostatic and hydrophobic interactions [12].

Other interactions of fpr

• Comparison of the sequence with those in the EMBL data library revealed a 99% identity between the last third of glpX and the first part of a gene called mvrA [9].
• Complete resonance assignments for the backbone of the MarA protein complexed with DNA oligomers corresponding to its binding sites at the mar, fumC, micF and the fpr promoters were obtained [13].

Analytical, diagnostic and therapeutic context of fpr

• UV-vis absorption, fluorescence, and CD spectroscopies of these FNR mutants (Lys75Arg, Lys75Gln, Lys75Ser, and Lys75Glu) indicate that all the mutated proteins folded properly and that significant protein structural rearrangements did not occur [11].

References