23 research outputs found
The utilization of oat polar lipids produced by supercritical fluid technologies in the encapsulation of probiotics
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Generation of Proton-Motive Force by an archaeal terminal quinol oxidase from Sulfolobus acidocaldarius
Properties of the menaquinol oxidase (Qox) and of qox deletion mutants of Bacillus subtilis
EPR studies of cytochrome aa3 from Sulfolobus acidocaldarius. Evidence for a binuclear center in archaebacterial terminal oxidase
Physiological role of the respiratory quinol oxidase in the anaerobic nitrite-reducing methanotroph 'Candidatus Methylomirabilis oxyfera'
Wu ML, de Vries S, van Alen TA, et al. Physiological role of the respiratory quinol oxidase in the anaerobic nitrite-reducing methanotroph 'Candidatus Methylomirabilis oxyfera'. Microbiology. 2011;157(3):890-898.The anaerobic nitrite-reducing methanotroph 'Candidatus Methylomirabilis oxyfera' ('Ca. M. oxyfera') produces oxygen from nitrite by a novel pathway. The major part of the O-2 is used for methane activation and oxidation, which proceeds by the route well known for aerobic methanotrophs. Residual oxygen may serve other purposes, such as respiration. We have found that the genome of 'Ca. M. oxyfera' harbours four sets of genes encoding terminal respiratory oxidases: two cytochrome c oxidases, a third putative bo-type ubiquinol oxidase, and a cyanide-insensitive alternative oxidase. Illumine sequencing of reverse-transcribed total community RNA and quantitative real-time RT-PCR showed that all four sets of genes were transcribed, albeit at low levels. Oxygen-uptake and inhibition experiments, UV-visible absorption spectral characteristics and EPR spectroscopy of solubilized membranes showed that only one of the four oxidases is functionally produced by 'Ca. M. oxyfera', notably the membrane-bound bo-type terminal oxidase. These findings open a new role for terminal respiratory oxidases in anaerobic systems, and are an additional indication of the flexibility of terminal oxidases, of which the distribution among anaerobic micro-organisms may be largely underestimated