Disease relevance of mioC

• In Escherichia coli, gidA and dnaA transcription are shut off transiently after initiation of chromosome replication, while mioC transcription is shut off before initiation [1].
• The nifJ gene of Klebsiella pneumoniae encodes an oxidoreductase required for the transfer of electrons from pyruvate to flavodoxin, which reduces nitrogenase [2].
• To investigate whether flavodoxins can serve as useful models of the analogous domain in P450 reductase, we have examined the FNR-Fld system from the cyanobacterium Anabaena [3].
• SiR-FP domains involved in binding FMN, FAD, and NADPH are proposed from amino acid sequence homologies with Desulfovibrio vulgaris flavodoxin (Dubourdieu, M., and Fox, J.L. (1977) J. Biol. Chem. 252, 1453-1463) and spinach ferredoxin-NADP+ oxidoreductase (Karplus, P.A., Walsh, K.A., and Herriott, J. R. (1984) Biochemistry 23, 6576-6583) [4].
• Chemical synthesis and expression of a synthetic gene for the flavodoxin from Clostridium MP [5].

High impact information on mioC

• IspH protein could also be activated by a mixture of flavodoxin, flavodoxin reductase, and NADPH at a rate of 3 nmol x min(-1) x mg(-1) [6].
• We address this issue by using NMR chemical shift mapping to identify the surfaces on flavodoxin that bind flavodoxin reductase and methionine synthase [7].
• A role for reduced ferredoxin and flavodoxin in the adaptive soxRS response to oxidative stress and in the regulation of the redox status of soxR is discussed [8].
• The structure revealed that each monomer of AzoR has a flavodoxin-like structure, without the explicit overall amino acid sequence homology [9].
• Fd-epsilon(88-stop) caused higher rates of uncoupled ATP hydrolysis than Fd-epsilon, and epsilon(88-stop) showed an increased rate of membrane-bound ATP hydrolysis but decreased proton pumping relative to the wild type [10].

Chemical compound and disease context of mioC

• Mutagenesis of two acidic Anabaena Fld residues (D144A and E145A) significantly decreased flavodoxin-supported P450c17 progesterone 17alpha-hydroxylase activity [3].
• Postulating the native E. coli flavodoxin/flavodoxin reductase system might mimic the natural redox partners of P450(cin), it was expressed in E. coli in the presence of cineole 1 [11].
• (1)H-(1)H residual dipolar couplings (RDCs) have been measured in two alignment media for 57 out of 70 possible methyl containing residues in the 167-residue flavodoxin-like domain of the E. coli sulfite reductase [12].
• Together with flavodoxin, the enzyme is involved in the reductive activation of three E. coli enzymes: cobalamin-dependent methionine synthase, pyruvate formate lyase and anaerobic ribonucleotide reductase [13].
• Reduced flavodoxin donates an electron for this reaction in E. coli, and S-adenosylmethionine serves as the methyl donor [14].

Biological context of mioC

• It is proposed that mioC transcription prevents initiation of chromosome replication, and must terminate before replication can begin [15].
• These results suggest that coupled transcription starting from the gid as well as the mioC promoter activates initiation of plasmid replication, the major contribution being made by gid transcription [16].
• These transcripts, originating either at the mioC and/or the ansC promoter traverse the replication origin [17].
• Flow cytometry was employed to study the DNA replication control and growth pattern of the resulting mioC mutants [18].
• All parameters measured (growth rate, cell size, DNA/cell, number of origins per cell, timing of initiation) were the same for the wild type and all the mioC mutant cells under steady state growth and after different shifts in growth medium and after induction of the stringent response [18].

Anatomical context of mioC

• The reactions could be supported by E. coli cytosol or by purified E. coli flavodoxin and NADPH-flavodoxin reductase [19].

Associations of mioC with chemical compounds

• It was further shown that mioC transcription was present throughout the induction of initiation by addition of chloramphenicol to a dnaA5(Ts) mutant growing at a semipermissive temperature [20].
• The presence of flavin mononucleotide and the primary sequence similarity to flavodoxin suggest that MioC may function as an electron transport protein [21].
• We have previously identified two of these proteins as flavodoxin and ferredoxin (flavodoxin) NADP(+) reductase [21].
• In addition, domains homologous to flavodoxin are components of the multidomain flavoproteins cytochrome P450 reductase, nitric oxide synthase, and methionine synthase reductase [7].
• Formation of the glycyl radical in the inactive enzyme requires S-adenosylmethionine (AdoMet), dithiothreitol, K+, and either an enzymatic (reduced flavodoxin) or chemical (dithionite or 5-deazaflavin plus light) reducing system [22].

Other interactions of mioC

• In both seqA- and dam- cells, gidA and dnaA continued to be transcribed after initiation, whereas the inhibition of mioC transcription before initiation was unaltered [1].
• PS I complexes isolated from the menA and menB mutant strains contain the full complement of polypeptides, show photoreduction of F(A) and F(B) at 15 K, and support 82-84% of the wild type rate of electron transfer from cytochrome c(6) to flavodoxin [23].

Analytical, diagnostic and therapeutic context of mioC

• Titration of DnaA protein correlated with repression of the mioC promoter [24].
• The gene coding for flavodoxin from Anabaena PCC 7119 was cloned by using the polymerase chain reaction (PCR) [25].
• To characterize the binding interface between E. coli flavodoxin and methionine synthase, we have employed site-directed mutagenesis and chemical cross-linking using carbodiimide and N-hydroxysuccinimide [14].
• The overall fold of SiR-FP18 is very similar to that of bacterial flavodoxins and of the flavodoxin-like domain in CPR or P450-BM3 [26].
• Protein engineering on Arg100 and Arg264 from Anabaena PCC 7119 FNR has been carried out to investigate their roles in complex formation and electron transfer to NADP+ and to ferredoxin/flavodoxin [27].

References