Iron-sulfur flavoproteins (Isf) are flavin mononucleotide (FMN)- and FeS cluster-containing proteins commonly encountered in anaerobic prokaryotes. However, with the exception of Isf from Methanosarcina thermophila, which participates in oxidative stress management by removing oxygen and hydrogen peroxide, none of these proteins has been characterized in terms of function. Trichomonas vaginalis, a sexually transmitted eukaryotic parasite of humans, was found to express several iron-sulfur flavoprotein (TvIsf) homologs in its hydrogenosomes. We show here that in addition to having oxygen-reducing activity, the recombinant TvIsf also functions as a detoxifying reductase of metronidazole and chloramphenicol, both of which are antibiotics effective against a variety of anaerobic microbes. TvIsf can utilize both NADH and reduced ferredoxin as electron donors. Given the prevalence of Isf in anaerobic prokaryotes, we propose that these proteins are central to a novel defense mechanism against xenobiotics.

• MeSH
• antitrichomonádové látky farmakologie   MeSH
• ferredoxiny metabolismus   MeSH
• flavoproteiny metabolismus   MeSH
• geny hub MeSH
• katalýza MeSH
• léková rezistence MeSH
• metronidazol chemie   farmakologie   MeSH
• molekulární sekvence - údaje MeSH
• NAD metabolismus   MeSH
• proteiny obsahující železo a síru metabolismus   MeSH
• sekvence aminokyselin MeSH
• subcelulární frakce účinky léků   metabolismus   MeSH
• Trichomonas vaginalis metabolismus   MeSH
• vodík metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• Konspekt
• Biochemie. Molekulární biologie. Biofyzika
• NLK Obory
• biochemie
• chemie, klinická chemie

UNLABELLED: FerB is a flavin mononucleotide (FMN)-containing NAD(P)H: acceptor oxidoreductase of unknown function that is found in the cytoplasm of the bacterium Paracoccus denitrificans. Based on measurements of fluorescence anisotropy, we report here that recombinant FerB readily binds to artificial membrane vesicles. If ubiquinone is incorporated into the membrane, FerB catalyzes its conversion to ubihydroquinone, which may be followed fluorimetrically (with ferricyanide and pyranine entrapped inside the liposomes) or by HPLC. FerB also reduces exogenously added superoxide or superoxide that has been enzymatically generated by the xanthine/xanthine oxidase system or P. denitrificans membrane vesicles. In whole cells, deficiency of FerB increases sensitivity to methyl viologen, as indicated by a lower growth rate and increased production of reactive aldehydes (by-products of lipid oxidation). Taken together, these data support a role for FerB in protection of cells against lipid peroxidation-mediated oxidative stress, and suggest that FerB is a prokaryotic counterpart of mammalian NAD(P)H: quinone oxidoreductase 1.

• MeSH
• antioxidancia chemie   metabolismus   MeSH
• flavoproteiny chemie   metabolismus   MeSH
• kinetika MeSH
• membránové proteiny chemie   metabolismus   MeSH
• oxidace-redukce MeSH
• oxidační stres * MeSH
• Paracoccus denitrificans enzymologie   MeSH
• superoxidy metabolismus   MeSH
• ubichinon metabolismus   MeSH
• xanthin metabolismus   MeSH
• xanthinoxidasa metabolismus   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• flaviny MeSH
• flavoproteiny MeSH

• Konspekt
• Biochemie. Molekulární biologie. Biofyzika
• NLK Obory
• biochemie

Glutarová acidurie II. typu neboli mnohočetný deficit acyl-CoA dehydrogenáz (MIM 231680) je klinicky i geneticky heterogenní, autozomálně recesivně dědičná metabolická porucha, biochemicky charakterizovaná akumulací specifických metabolitů v důsledku omezené kapacity flavinových dehydrogenáz předávajících elektrony do systému elektrony přenášejícího flavoproteinu (ETF) a elektrony přenášející flavoprotein:ubichinon oxidoreduktázy (ETF:QO). Klinické fenotypy zahrnují mimo letální neonatální formy také onemocnění s pozdním začátkem, jejichž hlavním projevem je kromě atak hypoketotické hypoglykemie myopatický syndrom s proximálním maximem. Incidenci myopatické formy glutarové acidurie II. typu literární zdroje neuvádějí, nicméně díky snadnější dostupnosti moderních diagnostických metod, včetně tandemové hmotnostní spektrometrie, a rostoucí informovanosti kliniků trvale stoupá počet nově diagnostikovaných pacientů. Kazuistika našeho pacienta, diagnostikovaného poprvé v České republice až na úrovni DNA, ilustruje jak klinický průběh onemocnění, tak možnosti diagnostiky a terapie, a mohla by tak být inspirací pro neurologickou praxi.

Glutaric aciduria type II or multiple acyl-CoA dehydrogenase deficiency (MIM 231680) is an autosomal recessively inherited disorder with heterogeneous clinical manifestation and genetic background, biochemically characterized by the accumulation of specific metabolites sourcing from the deficient capacity of flavin oxidative enzymes transferring electrons into the system of electron-transfer flavoprotein (ETF) and electron-transfer flavoprotein: ubiquinone oxidoreductase (ETF:QO). Clinical phenotypes include not only the lethal neonatal forms, but also the late-onset disorder, which usually manifests with proximal myopathic syndrome and sometimes with attacks of hypoketotic hypoglycemia. The incidence of the myopathic form of type II glutaric aciduria has not been determined; nevertheless, owing to easier access to novel diagnostic methods, including tandem mass spectrometry, and the ever increasing awareness of clinicians, the number of diagnosed patients has been growing constantly. The case report of our patient, for the first time diagnosed on the DNA level in the Czech Republic, illustrates not only the clinical course of the disease, but also the possibilities of diagnostics and therapy. It might serve as an inspiration for neurological practice.

• MeSH
• biopsie metody   využití   MeSH
• diagnostické techniky neurologické využití   MeSH
• dospělí MeSH
• elektromyografie metody   využití   MeSH
• financování organizované MeSH
• genetické markery MeSH
• klinické laboratorní techniky metody   využití   MeSH
• klinický obraz nemoci MeSH
• lidé MeSH
• mnohočetný deficit acyl-CoA dehydrogenáz diagnóza   etiologie   terapie   MeSH
• myotonické poruchy diagnóza   etiologie   terapie   MeSH
• riboflavin terapeutické užití   MeSH
• sacharidy terapeutické užití   MeSH
• tandemová hmotnostní spektrometrie metody   využití   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

• MeSH
• flavoproteiny MeSH
• fytosteroly MeSH
• kanabinoidy izolace a purifikace   MeSH
• mastné kyseliny izolace a purifikace   MeSH

• MeSH
• Basidiomycota enzymologie   mikrobiologie   růst a vývoj   MeSH
• flavoproteiny analýza   chemie   metabolismus   MeSH
• karbohydrátdehydrogenasy analýza   chemie   metabolismus   MeSH
• kořeny rostlin mikrobiologie   MeSH
• oxidoreduktasy analýza   chemie   metabolismus   MeSH

• MeSH
• biflavonoidy izolace a purifikace   MeSH
• finanční podpora výzkumu jako téma MeSH
• flavoproteiny izolace a purifikace   MeSH
• ostropestřec mariánský terapeutické užití   MeSH
• rostlinné extrakty farmakologie   terapeutické užití   MeSH

FerB is a cytoplasmic flavoprotein from the soil bacterium Paracoccus denitrificans with a putative role in defense against oxidative stress. To further explore this hypothesis, we compared protein variations upon methyl viologen treatment in wild-type and FerB mutant strains by a quantitative proteomic analysis based on iTRAQ-3DLC-MS/MS analysis. The proteins showing the most prominent increase in abundance were assigned to carbon fixation and sulfur assimilatory pathways. By employing these proteins as indirect markers, oxidative stress was found to be 15% less severe in the wild-type than in the FerB-deficient mutant cells. Oxidative stress altered the levels of proteins whose expression is dependent on the transcriptional factor FnrP. The observed down-regulation of the fnrP regulon members, most notably that of nitrous oxide reductase, was tentatively explained by an oxidative degradation of the [4Fe-4S] center of FnrP leading to a protein form which no longer activates transcription. While the level of FerB remained relatively constant, two proteins homologous to FerB accumulated during oxidative stress. When their genes were expressed in Escherichia coli, neither of the protein products contained a bound flavin, whereas they both had a high activity of flavin reductase, one preferentially utilizing NADH and the other NADPH.

• MeSH
• bakteriální proteiny biosyntéza   genetika   MeSH
• flavoproteiny genetika   metabolismus   MeSH
• mutace * MeSH
• oxidační stres účinky léků   genetika   MeSH
• Paracoccus denitrificans genetika   metabolismus   MeSH
• paraquat farmakologie   MeSH
• proteomika MeSH
• regulace genové exprese u bakterií účinky léků   genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• barva MeSH
• bilirubin MeSH
• corpus luteum MeSH
• flavony MeSH
• flavoproteiny MeSH
• vaječný žloutek MeSH