Coenzyme F(420)-dependent sulfite reductase (Fsr) of Methanocaldococcus jannaschii, a sulfite-tolerant methanogen, was expressed with activity in Methanococcus maripaludis, a sulfite-sensitive methanogen. The recombinant organism reduced sulfite to sulfide and grew with sulfite as the sole sulfur source, indicating that Fsr is a sulfite detoxification and assimilation enzyme for methanogens and...

Studies of the effect of substitution with 170 on the e.p.r. spectra at 9 and 35 GHz of Mo(V) in the phosphate complex of sulphite oxidase are reported. Substitution of '7O-enriched water for normal water, for samples of the enzymes reduced by sulphite in the presence of normal phosphate, produced no detectable effect on the e.p.r. signal. If phosphate substituted with 170 was used, coupling du...

An estimated 500,000 individuals in the US, mostly steroid-dependent asthmatics, suffer severe adverse reactions to sulfites in foods, beverages, and pharmaceutical products. In an attempt to understand the pathogenesis of sulfite hypersensitivity, we have developed an assay for the determination of total serum sulfite by utilizing: (a) reductive release of serum protein-bound sulfite; (b) deri...

The oxidation of sulfite by Thiobacillus thiooxidans was studied at various pH values with changing concentrations of potassium sulfite. The optimal pH for sulfite oxidation by cells was a function of sulfite concentrations, rising with increasing substrate concentrations, while that by the cell extracts was unaffected. The sulfite oxidation by cells was inhibited at high sulfite concentrations...

A vena sativa , Chloroplasts, Protoplasts, Sulfite Efflux, Sulfite Uptake Processes of J5S-labelled sulfite uptake and efflux by oat protoplasts and their chloroplasts are very rapid: during the first minutes (or perhaps even seconds) after sulfite supply a state of equilibrium is established between the protoplasts and their chloroplasts and the incubation medium. Bicarbonate concentrations ra...

Candida albicans is an opportunistic fungal pathogen that is highly resistant to different oxidative stresses. How reactive sulfur species (RSS) such as sulfite regulate gene expression and the role of the transcription factor Zcf2 and the sulfite exporter Ssu1 in such responses are not known. Here, we show that C. albicans specifically adapts to sulfite stress and that Zcf2 is required for tha...