PubMed · 6772089
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
M D Levitt, J H Bond. 1980. Flatulence.. https://doi.org/10.1146/annurev.me.31.020180.001015
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Explore the source record for details and available documents.
Enhanced absorption is observed in the (15)N NMR spectra of (15)NO(-)(3) during decomposition of peroxynitrite and the peroxynitrite-CO(2) adduct at pH 5.25, indicating the formation of (15)NO(-)(3) in radical pairs [(15)NO(*)(2), HO(*)] and [(15)NO(*)(2), CO(*-)(3)]. During the reaction of peroxynitrite and the peroxynitrite-CO(2) adduct with L-tyrosine, the (15)N NMR signal of the nitration product 3-nitrotyrosine exhibits emission showing a radical pathway of its formation. The nuclear polarization is built up in radical pairs [(15)NO(*)(2), tyr(*)] generated by free radical encounters of nitrogen dioxide and tyrosinyl radicals. The (15)N NMR signal of (15)NO(-)(2) formed during reaction of peroxynitrite with L-tyrosine appears in emission. It is concluded that tyrosinyl radicals are generated by reaction of nitrogen dioxide with L-tyrosine. In contrast to this, (15)NO(-)(2) does not show (15)N chemically induced dynamic nuclear polarization (CIDNP) during reaction of the peroxynitrite-CO(2) adduct with L-tyrosine, indicating a different reaction mechanism, which is assumed to be a hydrogen transfer between CO(*-)(3) and L-tyrosine. Emission is also observed in the (15)N NMR signals of 2-nitro-4-fluorophenol, 3-nitro-4-hydroxyphenylacetic acid, 2-nitrophenol, and 4-nitrophenol during reaction of 4-fluorophenol, 4-hydroxyphenylacetic acid, and phenol with peroxynitrite and the peroxynitrite-CO(2) adduct. 3-Nitro-4-hydroxyphenylacetic acid is also observed in emission during reaction of phenylacetic acid with peroxynitrite, but is not formed with the peroxynitrite-CO(2) adduct. The magnitude of the (15)N CIDNP effect during reaction of peroxynitrite with 4-fluorophenol and of the peroxynitrite-CO(2) adduct with 4-fluorophenol and phenol is determined. It excludes the occurrence of nonradical reactions. Only weak emission signals are observed during the reaction of peroxynitrite with phenol in (15)NO(-)(2), 2-nitrophenol, and 4-nitrophenol. 2-Nitrophenol is only formed in traces, and 4-nitrophenol is only formed in higher yields. The latter might be generated in part via a nonradical pathway.
Pseudomonas stutzeri strain KC was originally characterized as having, under iron-limiting conditions, novel carbon tetrachloride (CCl(4)) dehalogenation activity, specifically, a net conversion of CCl(4) to CO(2). The exact pathway and reaction mechanisms are unknown, but chloroform is not an intermediate and thiophosgene and phosgene have been identified as intermediates in trapping experiments. Previous work by others using cell-free preparations has shown that cell-free culture supernatants that have been passed through a low-molecular-weight cutoff membrane can confer rapid CCl(4) transformation ability upon cultures of bacteria which otherwise show little or no reactivity toward CCl(4). We used a cell-free assay system to monitor the complete purification of compounds showing CCl(4) degradation activity elaborated by iron-limited cultures of strain KC. Electrospray tandem mass spectroscopy, NMR spectroscopy, and comparisons with synthetic material have identified pyridine-2,6-bis(thiocarboxylate) as a metabolite of strain KC which has CCl(4) transformation activity in the presence of chemical reductants, e.g., titanium[III] citrate or dithiothreitiol, or actively growing bacterial cultures.