Ethanedisulfonate is degraded via sulfoacetaldehyde in Ralstonia sp. strain EDS1

Aerobic enrichment cultures (11) yielded three cultures able to utilise ethane-1,2-disulfonate as sole source of carbon and energy in salts medium. Two pure cultures were obtained and we worked with strain EDS1, which was assigned to the genus Ralstonia on the basis of its 16S rDNA sequence and simple taxonomic tests. Strain EDS1 utilised at least seven alkane(di)sulfonates, ethane-1,2disulfonate, taurine, isethionate, sulfoacetate, sulfoacetaldehyde and propane-1,3-disulfonate, as well as methanesulfonate and formate. Growth with ethanedisulfonate was concomitant with substrate disappearance and the formation of 2 mol sulfate per mol substrate. The growth yield, 7 g protein (mol C)–1, indicated quantitative utilisation of the substrate. Ethanedisulfonate-dependent oxygen uptake of whole cells during growth rose to a maximum before the end of growth and then sank rapidly; this was interpreted as evidence for an inducible desulfonative oxygenase that was not active in cell extracts. Inducible sulfoacetaldehyde sulfo-lyase was detected at high activity. Inducible degradation of taurine or isethionate or sulfoacetate via sulfoacetaldehyde sulfo-lyase is interpreted from