Fredrickson J K, Balkwill D L, Romine M F, Shi T
Pacific Northwest National Laboratory, Richland, Washington 99352, USA.
J Ind Microbiol Biotechnol. 1999 Oct;23(4-5):273-283. doi: 10.1038/sj.jim.2900741.
Several new species of the genus Sphingomonas including S. aromaticivorans, S. stygia, and S. subterranea that have the capacity for degrading a broad range of aromatic compounds including toluene, naphthalene, xylenes, p-cresol, fluorene, biphenyl, and dibenzothiophene, were isolated from deeply-buried (>200 m) sediments of the US Atlantic coastal plain (ACP). In S. aromaticivorans F199, many of the genes involved in the catabolism of these aromatic compounds are encoded on a 184-kb conjugative plasmid; some of the genes involved in aromatic catabolism are plasmid-encoded in the other strains as well. Members of the genus Sphingomonas were common among aerobic heterotrophic bacteria cultured from ACP sediments and have been detected in deep subsurface environments elsewhere. The major source of organic carbon for heterotrophic metabolism in ACP deep aquifers is lignite that originated from plant material buried with the sediments. We speculate that the ability of the subsurface Sphingomonas strains to degrade a wide array of aromatic compounds represents an adaptation for utilization of sedimentary lignite. These and related subsurface Sphingomonas spp may play an important role in the transformation of sedimentary organic carbon in the aerobic and microaerobic regions of the deep aquifers of the ACP.
鞘氨醇单胞菌属（Sphingomonas）的几个新物种，包括芳香鞘氨醇单胞菌（S. aromaticivorans）、斯氏鞘氨醇单胞菌（S. stygia）和地下鞘氨醇单胞菌（S. subterranea），它们能够降解多种芳香族化合物，包括甲苯、萘、二甲苯、对甲酚、芴、联苯和二苯并噻吩，这些菌株是从美国大西洋沿岸平原（ACP）深度埋藏（>200米）的沉积物中分离出来的。在芳香鞘氨醇单胞菌F199中，许多参与这些芳香族化合物分解代谢的基因都编码在一个184 kb的接合质粒上；其他菌株中一些参与芳香族分解代谢的基因也是质粒编码的。鞘氨醇单胞菌属成员在从ACP沉积物中培养的好氧异养细菌中很常见，并且在其他地方的深部地下环境中也被检测到。ACP深层含水层中异养代谢的主要有机碳来源是褐煤，它源自与沉积物一起埋藏的植物材料。我们推测，地下鞘氨醇单胞菌菌株降解多种芳香族化合物的能力代表了对沉积褐煤利用的一种适应。这些以及相关的地下鞘氨醇单胞菌物种可能在ACP深层含水层好氧和微氧区域的沉积有机碳转化中发挥重要作用。
