Über das 2.3‐Dimethyl‐naphthalin im Steinkohlenteer

Kruber, O.

doi:10.1002/cber.19290621117

Cited by 14 publications

(5 citation statements)

References 3 publications

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“…2,3‐Dimethoxy‐5,6‐dimethyl‐p‐benzoquinone (DDB) was acquired from Sequoia Research Products. 2,3‐Dimethyl‐1,4‐naphthoquinone (DMN) was synthesized from menadione (Sigma Aldrich) (Kruber, ). 2‐n‐Heptyl‐4‐hydroxyquinoline‐N‐oxide (HQNO) was provided by Alexis Biochemicals and the Protease inhibitors cocktail tablets by Roche.…”

Section: Methodsmentioning

confidence: 99%

Type‐II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction

Sena

Batista

Catarino

et al. 2015

Molecular Microbiology

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SummaryA prerequisite for any rational drug design strategy is understanding the mode of protein-ligand interaction. This motivated us to explore protein-substrate interaction in Type-II NADH:quinone oxidoreductase (NDH-2) from Staphylococcus aureus, a worldwide problem in clinical medicine due to its multiple drug resistant forms. NDHs-2 are involved in respiratory chains and recognized as suitable targets for novel antimicrobial therapies, as these are the only enzymes with NADH:quinone oxidoreductase activity expressed in many pathogenic organisms.We obtained crystal and solution structures of NDH-2 from S. aureus, showing that it is a dimer in solution. We report fast kinetic analyses of the protein and detected a charge-transfer complex formed between NAD + and the reduced flavin, which is dissociated by the quinone. We observed that the quinone reduction is the rate limiting step and also the only half-reaction affected by the presence of HQNO, an inhibitor. We analyzed protein-substrate interactions by fluorescence and STD-NMR spectroscopies, which indicate that NADH and the quinone bind to different sites. In summary, our combined results show the presence of distinct binding sites for the two substrates, identified quinone reduction as the rate limiting step and indicate the establishment of a NAD + -protein complex, which is released by the quinone.

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Section: Methodsmentioning

confidence: 99%

Type‐II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction

Sena

Batista

Catarino

et al. 2015

Molecular Microbiology

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“…The reaction mixture contained membrane vesicles in 2.5 mM HEPES–Tris pH 7.5, 5 mM K 2 SO 4 , 25 mM Na 2 SO 4 , 100 μM quinone (2,3‐dimethyl‐1,4‐naphthoquinone (DMN) or decylubiquinone (DUQ)) and 100 μM K 2 ‐NADH or reduced nicotinamide hypoxanthine dinucleotide (deamino‐NADH). DMN was synthesized as described in [27]. The obtained data are the average of at least three independent assays.…”

Section: Methodsmentioning

confidence: 99%

Respiratory complex I from Escherichia coli does not transport Na⁺ in the absence of its NuoL subunit

2014

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a b s t r a c tWe investigated H + and Na + transport by complex I from Escherichia coli devoid of the NuoL subunit, which is probably part of the ion translocating machinery. We observed that complex I devoid of the NuoL subunit still translocates H + , although to a smaller extension than the complete version of complex I, but does not transport Na + . Our results unequivocally reinforce the observation that E. coli complex I transports Na + in the opposite direction to that of the H + and show that NuoL subunit is involved in the translocation of both ions by complex I.

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“…Protein concentrations were determined by the method of Schmidt et al (63). All specialty chemicals were obtained from Sigma with the exceptions of TCS (3,3=,4=,5-tetrachlorosalicylanilide; Kodak) and DMN (2,3-dimethyl-1,4-naphthoquinone; synthesized according to the method of Kruber [43]; gift from the late A. Kröger, Frankfurt, Germany). Spectrophotometric enzyme assays.…”

Section: Figmentioning

confidence: 99%

Thiosulfate Reduction in Salmonella enterica Is Driven by the Proton Motive Force

et al. 2012

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Thiosulfate respiration in Salmonella enterica serovar Typhimurium is catalyzed by the membrane-bound enzyme thiosulfate reductase. Experiments with quinone biosynthesis mutants show that menaquinol is the sole electron donor to thiosulfate reductase. However, the reduction of thiosulfate by menaquinol is highly endergonic under standard conditions (⌬E°= ‫؍‬ ؊328 mV). Thiosulfate reductase activity was found to depend on the proton motive force (PMF) across the cytoplasmic membrane. A structural model for thiosulfate reductase suggests that the PMF drives endergonic electron flow within the enzyme by a reverse loop mechanism. Thiosulfate reductase was able to catalyze the combined oxidation of sulfide and sulfite to thiosulfate in a reverse of the physiological reaction. In contrast to the forward reaction the exergonic thiosulfate-forming reaction was PMF independent. Electron transfer from formate to thiosulfate in whole cells occurs predominantly by intraspecies hydrogen transfer.

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Über das 2.3‐Dimethyl‐naphthalin im Steinkohlenteer

Cited by 14 publications

References 3 publications

Type‐II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction

Type‐II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction

Respiratory complex I from Escherichia coli does not transport Na⁺ in the absence of its NuoL subunit

Thiosulfate Reduction in Salmonella enterica Is Driven by the Proton Motive Force

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Über das 2.3‐Dimethyl‐naphthalin im Steinkohlenteer

Cited by 14 publications

References 3 publications

Type‐II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction

Type‐II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction

Respiratory complex I from Escherichia coli does not transport Na+ in the absence of its NuoL subunit

Thiosulfate Reduction in Salmonella enterica Is Driven by the Proton Motive Force

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Respiratory complex I from Escherichia coli does not transport Na⁺ in the absence of its NuoL subunit