Department of Microbiology, IWWR, Radboud University Nijmegen, Nijmegen, The Netherlands.
FEMS Microbiol Ecol. 2009 Dec;70(3):483-92. doi: 10.1111/j.1574-6941.2009.00765.x. Epub 2009 Aug 19.
The oxidation of dimethylsulfide and methanethiol by sulfate-reducing bacteria (SRB) was investigated in Tanzanian mangrove sediments. The rate of dimethylsulfide and methanethiol accumulation in nonamended sediment slurry (control) incubations was very low while in the presence of the inhibitors tungstate and bromoethanesulfonic acid (BES), the accumulation rates ranged from 0.02-0.34 to 0.2-0.4 nmol g FW sediment(-1) h(-1), respectively. Degradation rates of methanethiol and dimethylsulfide added were 2-10-fold higher. These results point to a balance of production and degradation. Degradation was inhibited much stronger by tungstate than by BES, which implied that SRB were more important. In addition, a new species of SRB, designated strain SD1, was isolated. The isolate was a short rod able to utilize a narrow range of substrates including dimethylsulfide, methanethiol, pyruvate and butyrate. Strain SD1 oxidized dimethylsulfide and methanethiol to carbon dioxide and hydrogen sulfide with sulfate as the electron acceptor and exhibited a low specific growth rate of 0.010 +/- 0.002 h(-1), but a high affinity for its substrates. The isolated microorganism could be placed in the genus Desulfosarcina (the most closely related cultured species was Desulfosarcina variabilis, 97% identity). Strain SD1 represents a member of the dimethylsulfide/methanethiol-consuming SRB population in mangrove sediments.
在坦桑尼亚红树林沉积物中研究了硫酸盐还原菌（SRB）对二甲基硫和甲硫醇的氧化作用。在未添加抑制剂的沉积物悬浮液（对照）培养物中，二甲基硫和甲硫醇的积累速率非常低，而在钨酸盐和溴乙磺酸盐（BES）存在的情况下，积累速率分别为 0.02-0.34 至 0.2-0.4 nmol g FW 沉积物（-1）h（-1）。添加的甲硫醇和二甲基硫的降解速率高 2-10 倍。这些结果表明存在生产和降解的平衡。钨酸盐对降解的抑制作用比 BES 强得多，这意味着 SRB 更为重要。此外，还分离出了一种新的 SRB，命名为 SD1 株。该分离物是一种短杆状菌，能够利用包括二甲基硫、甲硫醇、丙酮酸盐和丁酸盐在内的窄范围的底物。SD1 株将二甲基硫和甲硫醇氧化为二氧化碳和硫化氢，硫酸盐作为电子受体，并表现出低的特定生长速率（0.010 +/- 0.002 h（-1）），但对其底物具有高亲和力。分离出的微生物可归入脱硫弧菌属（最密切相关的培养物种是脱硫弧菌，同源性为 97%）。SD1 株代表红树林沉积物中二甲基硫/甲硫醇消耗型 SRB 种群的一个成员。
