Cysteine Reactivity and Thiol−Disulfide Interchange Pathways in AhpF and AhpC of the Bacterial Alkyl Hydroperoxide Reductase System
نویسندگان
چکیده
منابع مشابه
Cysteine reactivity and thiol-disulfide interchange pathways in AhpF and AhpC of the bacterial alkyl hydroperoxide reductase system.
AhpC and AhpF from Salmonella typhimurium undergo a series of electron transfers to catalyze the pyridine nucleotide-dependent reduction of hydroperoxide substrates. AhpC, the peroxide-reducing (peroxiredoxin) component of this alkyl hydroperoxidase system, is an important scavenger of endogenous hydrogen peroxide in bacteria and acts through a reactive, peroxidatic cysteine, Cys46, and a secon...
متن کاملSupplemental Data: Cysteine reactivity and thiol-disulfide interchange pathways in AhpF and AhpC of the bacterial alkyl hydroperoxide reductase
METHODS Spectral and Anaerobic Measurements. All absorbance spectra and anaerobic titrations employed the thermostatted Milton Roy Spectronic 3000 diode array spectrophotometer. The oxidoreductase and DTNB assays were performed on a thermostatted Applied Photophysics DX.17MV stopped-flow spectrofluorometer. The molar extinction coefficients of the proteinbound FAD at 448 or 449 nm were determin...
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The two components, AhpF and AhpC, of the Salmonella typhimurium alkyl hydroperoxide reductase enzyme system have been overexpressed and purified from Escherichia coli for investigations of their catalytic properties. Recombinant proteins were isolated in high yield (25-33 mg per liter of bacterial culture) and were shown to impart a high degree of protection against killing by cumene hydropero...
متن کاملRoles for the two cysteine residues of AhpC in catalysis of peroxide reduction by alkyl hydroperoxide reductase from Salmonella typhimurium.
The catalytic properties of cysteine residues Cys46 and Cys165, which form intersubunit disulfide bonds in the peroxidatic AhpC protein of the alkyl hydroperoxide reductase (AhpR) system from Salmonella typhimurium, have been investigated. The AhpR system, composed of AhpC and a flavoprotein reductase, AhpF, catalyzes the pyridine nucleotide-dependent reduction of organic hydroperoxides and hyd...
متن کاملIsolation and analysis of the Xanthomonas alkyl hydroperoxide reductase gene and the peroxide sensor regulator genes ahpC and ahpF-oxyR-orfX.
From Xanthomonas campestris pv. phaseoli, we have isolated by two independent methods genes involved in peroxide detoxification (ahpC and ahpF), a gene involved in peroxide sensing and transcription regulation (oxyR), and a gene of unknown function (orfX). Amino acid sequence analysis of AhpC, AhpF, and OxyR showed high identity with bacterial homologs. OrfX was a small cysteine-rich protein wi...
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ژورنال
عنوان ژورنال: Biochemistry
سال: 2007
ISSN: 0006-2960,1520-4995
DOI: 10.1021/bi7001218