海洋中的細菌Alcanivorax borkumensis是一種能“吃”石油的細菌,，它在清除溢入海洋的石油的工作中發(fā)揮了關(guān)鍵作用,，因此也被稱為是石油去污菌。研究人員在8月出版的《自然—生物技術(shù)》上報告說,，他們測出了A. borkumensis的全部基因組序列,，從而為認識這種細菌的生物化學(xué)功能和生理適應(yīng)性提供了一個完整的藍圖，正是這些特性賦予這種細菌有效分解海洋中原油的能力,。
或是偶然事故或是故意為之,，每年會有約130萬噸石油被傾入大海，但其中只有小部分是因油輪事故造成的,。老天保佑,，海洋中的部分細菌能消化石油中的碳氫化合物，因此,，傾瀉入海洋的石油能夠慢慢被降解,。
Schneiker和同事測出了長度達3.1Mb的A. borkumensis基因組序列。在吃石油的細菌中,，A. borkumensis的獨特之處在于只有它能消化或降解呈線性或枝狀結(jié)構(gòu)的有機化合物——烷烴,，這類物質(zhì)是原油的兩種主要成分。A. borkumensis的基因組序列含有2755個可預(yù)測的開放閱讀框架,，包括降解烷烴,、乳化石油化合物和胞外聚合物的系統(tǒng)，正是這些功能系統(tǒng)讓A. borkumensis能夠消化石油,。
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.
