Tanimoto Y, Bak F
Max-Planck-Institut für Terrestrische Mikrobiologie, Marburg (Lahn), Federal Republic of Germany.
Appl Environ Microbiol. 1994 Jul;60(7):2450-5. doi: 10.1128/aem.60.7.2450-2455.1994.
The complete oxidation of methylmercaptan (MSH) and dimethyl sulfide (DMS) with sulfate or nitrate as electron acceptors was observed in enrichment cultures and dilution series using thermophilic fermentor sludge as the inoculum. Three new strains of thermophilic sulfate reducers were isolated in pure culture (strains MTS5, TDS2, and SDN4). Strain MTS5 grew on MSH and strain TDS2 grew on DMS whereas strain SDN4 grew on either MSH or DMS. The cellular growth yields were 2.57 g (dry weight)/mol of MSH for strain MTS5 and 6.02 g (dry weight)/mol of DMS for strain TDS2. All strains used sulfate, sulfite, or thiosulfate as electron acceptors, but only strain SDN4 used nitrate. DMS and MSH were oxidized to CO2 and sulfide with either sulfate or nitrate as the electron acceptor. Sulfate was stoichiometrically reduced to sulfide while nitrate was reduced to ammonium. All strains were motile rods, required biotin for growth, lacked desulfoviridin, had DNA with G+C contents of 48 to 57 mol% and probably belonged to the genus Desulfotomaculum. This is the first report of the oxidation of MSH and DMS by pure cultures of sulfate-reducing bacteria.
在以嗜热发酵罐污泥为接种物的富集培养物和稀释系列中，观察到以硫酸盐或硝酸盐作为电子受体时，甲硫醇（MSH）和二甲基硫醚（DMS）的完全氧化。在纯培养物中分离出三株嗜热硫酸盐还原菌新菌株（菌株MTS5、TDS2和SDN4）。菌株MTS5以MSH为生长底物，菌株TDS2以DMS为生长底物，而菌株SDN4可以以MSH或DMS为生长底物。菌株MTS5的细胞生长产量为每摩尔MSH 2.57 g（干重），菌株TDS2的细胞生长产量为每摩尔DMS 6.02 g（干重）。所有菌株都使用硫酸盐、亚硫酸盐或硫代硫酸盐作为电子受体，但只有菌株SDN4使用硝酸盐。以硫酸盐或硝酸盐作为电子受体时，DMS和MSH被氧化为二氧化碳和硫化物。硫酸盐按化学计量还原为硫化物，而硝酸盐还原为铵。所有菌株均为运动性杆状菌，生长需要生物素，缺乏脱硫绿素，DNA的G+C含量为48至57 mol%，可能属于脱硫肠状菌属。这是关于硫酸盐还原菌纯培养物氧化MSH和DMS的首次报道。
