Anaerobic taurine oxidation: a novel reaction by a nitrate-reducing Alcaligenes sp.

Abstract

Enrichment cultures were prepared under strictly anoxic conditions in medium representing fresh water and containing an organosulfonate as electron donor and carbon source, and nitrate as electron acceptor. The inoculum was from the anaerobic digestor of two communal sewage works. The natural organosulfonates 2-aminoethanesulf onate (taurine), ~~-2-amino-3-sulfopropionate (cysteate) and 2-hydroxyethanesulf onate (isethionate) all gave positive enrichments, whereas unsubstituted alkanesulfonates, such as methanesulfonate and arenesulfonates, gave no enrichment. Two representative enrichments were used to obtain pure cultures, and strains NKNTAU (utilizing taurine) and NKNIS (utilizing isethionate) were isolated. Strain NKNTAU was examined in detail. Out of 18 tested organosulfonates, it utilized only one, taurine, and was identified as a novel AIcaligenes sp., a facultatively anaerobic bacterium. Carbon from taurine was converted to cell material and carbon dioxide. The amino group was released as ammonium ion and the sulfonate moiety was recovered as sulfate. Nitrate was reduced to nitrogen gas.

The DUF81 protein TauE in Cupriavidus necator H16, a sulfite exporter in the metabolism of C2 sulfonates

“…Growth was followed as turbidity (OD 580 ) and quantified as protein in a Lowry-type reaction (Cook & Hütter, 1981). Taurine was derivatized with dinitrofluorobenzene and quantified after separation by HPLC (Denger et al, 1997). Isethionate and sulfoacetate were determined by ion chromatography Styp von Rekowski et al, 2005).…”

Dissimilation of C3-sulfonates

“…L-Cysteate was later found to serve as an electron acceptor for several sulfate-or sulfitereducing bacteria (Laue et al 1997b;Lie et al 1996Lie et al , 1998Lie et al , 1999: the fate of the cysteate carbon is largely acetate, and the sulfonate sulfur is recovered as sulfide. L-Cysteate can serve as an electron donor for some nitrate-reducing bacteria (Denger et al 1997;Mikosch et al 1999). Paracoccus pantotrophus NKNCYSA grows exponentially with L-cysteate as the electron donor and nitrate as the electron acceptor, and excretes the sulfonate moiety as sulfate; the amino group is recovered largely as ammonium ion in the medium and in part in cell material (Mikosch et al 1999).…”

Genome-enabled analysis of the utilization of taurine as sole source of carbon or of nitrogen by Rhodobacter sphaeroides 2.4.1

“…Growth was followed as turbidity (OD 580 ) and quantified as protein in a Lowry-type reaction (Cook & Hütter, 1981). Taurine and alanine were derivatized with dinitrofluorobenzene and subjected to separation by HPLC (Denger et al, 1997). Sulfite was quantified as the fuchsin derivative as described elsewhere (Denger et al, 2001).…”