Microbial desulfonation

Abstract

Organosulfonates are widespread compounds, be they natural products of low or high molecular weight, or xenobiotics. Many commonly found compounds are subject to desulfonation, even if it is not certain whether all the corresponding enzymes are widely expressed in nature. Sulfonates require transport systems to cross the cell membrane, but few physiological data and no biochemical data on this topic are available, though the sequences of some of the appropriate genes are known. Desulfonative enzymes in aerobic bacteria are generally regulated by induction, if the sulfonate is serving as a carbon and energy source, or by a global network for sulfur scavenging (sulfate starvation induced (SSI) stimulon) if the sulfonate is serving as a source of sulfur. It is unclear whether an SSI regulation is found in anaerobes. The anaerobic bacteria examined can express the degradative enzymes constitutively, if the sulfonate is being utilized as a carbon source, but enzyme induction has also been observed. At least three general mechanisms of desulfonation are recognisable or postulated in the aerobic catabolism of sulfonates: (1) activate the carbon neighboring the C y Q bond and release of sulfite assisted by a thiamine pyrophosphate cofactor; (2) destabilize the C y Q bond by addition of an oxygen atom to the same carbon, usually directly by oxygenation, and loss of the good leaving group, sulfite; (3) an unidentified, formally reductive reaction. Under SSIS control, different variants of mechanism (2) can be seen. Catabolism of sulfonates by anaerobes was discovered recently, and the degradation of taurine involves mechanism (1). When anaerobes assimilate sulfonate sulfur, there is one common, unknown mechanism to desulfonate the inert aromatic compounds and another to desulfonate inert aliphatic compounds; taurine seems to be desulfonated by mechanism (1).

Characterization of the genes encoding the 3-carboxy-cis,cis-muconate-lactonizing enzymes from the 4-sulfocatechol degradative pathways of Hydrogenophaga intermedia S1 and Agrobacterium radiobacter S2

“…The microbial degradation of aromatic sulfonic acids has mainly been studied using simple benzenesulfonates and naphthalenesulfonates as model compounds. These studies demonstrated that sulfonated substrates are in most cases initially desulfonated by the action of ring-hydroxylating dioxygenases to the corresponding diols (Brilon et al, 1981;Cook et al, 1999;Nörtemann et al, 1986;Ohe et al, 1990;Thurnheer et al, 1990;Wittich et al, 1988). In contrast, it has been found that 4-aminobenzenesulfonate (sulfanilate) was initially deaminated by a co-culture of Hydrogenophaga intermedia S1 and Agrobacterium radiobacter S2 to 4-sulfocatechol (Feigel & Knackmuss, 1988).…”

Bioavailability of water-polluting sulfonoaromatic compounds

“…This is perhaps not surprising, given the large percentage of sulfonates in soil and sediment sulfur, and the facts that humic materials are sulfonates and subject to rapid¯ux in soil (reviewed in Cook et al 1998). What is less obvious in these reports is the frequency with which pure cultures are not obtained (e.g.…”

“…The degradation of organosulfonates as carbon sources for growth is characterised by organisms with narrow substrate ranges (one to three sulfonated compounds) (Cook et al 1998), though exceptions are known (see Haug et al 1991) and some naphthalenedisulfonates are biodegradable (e.g. Wittich et al 1988).…”

Changes in proportions of arsenic species within an Ecklonia radiata food chain

“…[46] Anaerobic desulfonation has been demonstrated during fermentation, resulting in the loss of SO 3 as sulfide or thiosulfate. [47] Although differential accumulation of PO 4 -riboside cannot be discounted, it is unlikely that high PO 4 -riboside concentrations in animal tissues are the result of direct ingestion, as their diet is composed of ∼79% SO 3 -riboside from E. radiata, (Table A4). PO 4 -riboside has been found previously as the sole arsenoriboside in the digestive gland of the western rock lobster Panulirus cygnus, and in mussels.…”