石油去污菌的基因组测序完成
海洋中的细菌Alcanivorax borkumensis是一种能“吃”石油的细菌，它在清除溢入海洋的石油的工作中发挥了关键作用，因此也被称为是石油去污菌。研究人员在8月出版的《自然—生物技术》上报告说，他们测出了A. borkumensis的全部基因组序列，从而为认识这种细菌的生物化学功能和生理适应性提供了一个完整的蓝图，正是这些特性赋予这种细菌有效分解海洋中原油的能力。
或是偶然事故或是故意为之，每年会有约130万吨石油被倾入大海，但其中只有小部分是因油轮事故造成的。老天保佑，海洋中的部分细菌能消化石油中的碳氢化合物，因此，倾泻入海洋的石油能够慢慢被降解。
Schneiker和同事测出了长度达3.1Mb的A. borkumensis基因组序列。在吃石油的细菌中，A. borkumensis的独特之处在于只有它能消化或降解呈线性或枝状结构的有机化合物——烷烃，这类物质是原油的两种主要成分。A. borkumensis的基因组序列含有2755个可预测的开放阅读框架，包括降解烷烃、乳化石油化合物和胞外聚合物的系统，正是这些功能系统让A. borkumensis能够消化石油。
英文原文：
Proteomic Insights into Metabolic Adaptations in Alcanivorax borkumensis Induced by Alkane Utilization
Alcanivorax borkumensis is a ubiquitous marine petroleum oil-degrading bacterium with an unusual physiology specialized for alkane metabolism. This "hydrocarbonoclastic" bacterium degrades an exceptionally broad range of alkane hydrocarbons but few other substrates. The proteomic analysis presented here reveals metabolic features of the hydrocarbonoclastic lifestyle. Specifically, hexadecane-grown and pyruvate-grown cells differed in the expression of 97 cytoplasmic and membrane-associated proteins whose genes appeared to be components of 46 putative operon structures. Membrane proteins up-regulated in alkane-grown cells included three enzyme systems able to convert alkanes via terminal oxidation to fatty acids, namely, enzymes encoded by the well-known alkB1 gene cluster and two new alkane hydroxylating systems, a P450 cytochrome monooxygenase and a putative flavin-binding monooxygenase, and enzymes mediating ß-oxidation of fatty acids. Cytoplasmic proteins up-regulated in hexadecane-grown cells reflect a central metabolism based on a fatty acid diet, namely, enzymes of the glyoxylate bypass and of the gluconeogenesis pathway, able to provide key metabolic intermediates, like phosphoenolpyruvate, from fatty acids. They also include enzymes for synthesis of riboflavin and of unsaturated fatty acids and cardiolipin, which presumably reflect membrane restructuring required for membranes to adapt to perturbations induced by the massive influx of alkane oxidation enzymes. Ancillary functions up-regulated included the lipoprotein releasing system (Lol), presumably associated with biosurfactant release, and polyhydroxyalkanoate synthesis enzymes associated with carbon storage under conditions of carbon surfeit. The existence of three different alkane-oxidizing systems is consistent with the broad range of oil hydrocarbons degraded by A. borkumensis and its ecological success in oil-contaminated marine habitats.
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