A toluene-degrading sulfate-reducing bacterium, strain Tol2, was isolated from marine sediment under strictly anoxic conditions. Toluene was toxic if applied directly to the medium at concentrations higher than 0.5 mM. To provide toluene continuously at a nontoxic concentration, it was supplied in an inert hydrophobic carrier phase. The isolate had oval, sometimes motile cells (1.2 to 1.4 by 1.2 to 2.0 microns). The doubling time was 27 h. Toluene was completely oxidized to CO2, as demonstrated by measurement of the degradation balance. The presence of carbon monoxide dehydrogenase and formate dehydrogenase indicated a terminal oxidation of acetyl coenzyme A via the CO dehydrogenase pathway. The use of hypothetical intermediates of toluene degradation was tested in growth experiments and adaptation studies with dense cell suspensions. Results do not support a degradation of toluene via one of the cresols or methylbenzoates, benzyl alcohol, or phenylacetate as free intermediate. Benzyl alcohol did not serve as growth substrate; moreover, it was a strong, specific inhibitor of toluene degradation, whereas benzoate utilization was not affected by benzyl alcohol. Sequencing of 16S rRNA revealed a relationship to the metabolically dissimilar genus Desulfobacter and on a deeper level to the genus Desulfobacterium. The new genus and species Desulfobacula toluolica is proposed.
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机译：在严格的缺氧条件下，从海洋沉积物中分离出了降解甲苯的硫酸盐还原菌Tol2。如果将甲苯直接以高于0.5 mM的浓度施于培养基中，会产生毒性。为了以无毒浓度连续提供甲苯，将其以惰性疏水载体相形式提供。分离物具有椭圆形的，有时可移动的细胞（1.2至1.4 x 1.2至2.0微米）。倍增时间为27小时。如降解平衡的测量所示，甲苯被完全氧化为CO2。一氧化碳脱氢酶和甲酸脱氢酶的存在表明乙酰辅酶A通过CO脱氢酶途径的最终氧化。假设的甲苯降解中间体的使用已在生长实验和稠密细胞悬浮液的适应性研究中进行了测试。结果不支持通过甲酚或甲基苯甲酸酯，苯甲醇或苯乙酸酯中的一种作为游离中间体降解甲苯。苯甲醇不能用作生长底物；此外，它是甲苯降解的强力特异性抑制剂，而苯甲酸酯的利用不受苯甲醇的影响。 16S rRNA的测序揭示了与代谢不同的脱硫杆菌属之间的关系，并且在更深层次上与脱硫细菌属有关。提出了新的属和物种Tosulfobacula toluolica。
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