Miralles Gilles, Nérini David, Manté Claude, Acquaviva Monique, Doumenq Pierre, Michotey Valérie, Nazaret Sylvie, Bertrand Jean Claude, Cuny Philippe
Laboratoire de Microbiologie, de Géochimie et d'Ecologie Marines, CNRS-UMR 6117, Centre d'Océanologie de Marseille, Cedex 9, Case 901, Campus de Luminy, Marseille, 13288, France.
Microb Ecol. 2007 Nov;54(4):646-61. doi: 10.1007/s00248-007-9221-6. Epub 2007 Mar 4.
The effects of spilled oil on sedimentary bacterial communities were examined in situ at 20 m water depth in a Mediterranean coastal area. Sediment collected at an experimental site chronically subjected to hydrocarbon inputs was reworked into PVC cores with or without a massive addition of crude Arabian light oil ( approximately 20 g kg(-1) dry weight). Cores were reinserted into the sediment and incubated in situ at the sampling site (20 m water depth) for 135 and 503 days. The massive oil contamination induced significant shifts in the structure of the indigenous bacterial communities as shown by ribosomal intergenic spacer analysis (RISA). The vertical heterogeneity of the bacterial communities within the sediment was more pronounced in the oiled sediments particularly after 503 days of incubation. Response to oil of the deeper depth communities (8-10 cm) was slower than that of superficial depth communities (0-1 and 2-4 cm). Analysis of the oil composition by gas chromatography revealed a typical microbial alteration of n-alkanes during the experiment. Predominant RISA bands in oiled sediments were affiliated to hydrocarbonoclastic bacteria sequences. In particular, a 395-bp RISA band, which was the dominant band in all the oiled sediments for both incubation times, was closely related to hydrocarbonoclastic sulfate-reducing bacteria (SRB). These bacteria may have contributed to the main fingerprint changes and to the observed biodegradation of n-alkanes. This study provides useful information on bacterial dynamics in anoxic contaminated infralittoral sediments and highlights the need to assess more precisely the contribution of SRB to bioremediation in oil anoxic contaminated areas.
在地中海沿海地区20米水深处，对泄漏石油对沉积细菌群落的影响进行了原位研究。在一个长期受到烃类输入影响的实验地点采集沉积物，将其重新装入聚氯乙烯岩芯中，分别添加或不添加大量阿拉伯轻质原油（约20克/千克干重）。将岩芯重新插入沉积物中，并在采样地点（20米水深处）原位培养135天和503天。核糖体基因间隔分析（RISA）结果表明，大量油污导致原生细菌群落结构发生显著变化。特别是在培养503天后，油污沉积物中细菌群落的垂直异质性更加明显。较深深度群落（8 - 10厘米）对石油的反应比浅表层群落（0 - 1厘米和2 - 4厘米）慢。通过气相色谱分析石油成分发现，实验过程中正构烷烃发生了典型的微生物变化。油污沉积物中主要的RISA条带与烃类分解细菌序列相关。特别是一条395碱基对的RISA条带，在两个培养时间的所有油污沉积物中都是主导条带，它与烃类分解硫酸盐还原菌（SRB）密切相关。这些细菌可能导致了主要的指纹图谱变化以及观察到的正构烷烃生物降解。本研究为缺氧污染潮下带沉积物中的细菌动态提供了有用信息，并强调需要更精确地评估硫酸盐还原菌在石油缺氧污染区域生物修复中的作用。
