生物谷報道：Syntrophus aciditrophicus是一種極端厭氧菌,，用以維持生命的食物非常簡單,，是為數(shù)不多的能夠降解有機物脂肪酸的生命形式,，在全球碳循環(huán)中發(fā)揮關(guān)鍵作用。最近加州大學(xué)洛杉磯分校的研究人員完成了其基因組測序工作,，共鑒別出3169個基因,。
大多數(shù)生命利用氧降解有機物獲得能量，反應(yīng)過程中產(chǎn)生的電子驅(qū)動儲存能量的ATP生成,。Syntrophus是極端厭氧菌,，不能進(jìn)行氧化作用，其電子流動方向與氧化作用中的電子傳遞方向相反,，反應(yīng)耗能,、產(chǎn)生氫和甲酸鹽（formate）。因此如果沒有消耗氫和甲酸鹽,、產(chǎn)能的其它細(xì)菌幫助,，Syntrophus不能生存,。
Robert Gunsalus小組鑒別出幾個Syntrophus參與反向電子轉(zhuǎn)移（耗能）的基因,，他們進(jìn)一步打算研究這種機制。“如果我們能夠弄清這種‘互養(yǎng)共棲新陳代謝’,，也許就能提高從廢物中獲取的氫量,，實現(xiàn)生物氫生產(chǎn),。”詳細(xì)研究內(nèi)容刊登于《PNAS》（DOI: 10.1073/pnas.0610456104）
英文原文：
Extreme-living bacteria has genome sequenced
22:00 16 April 2007 NewScientist.com news service Rowan Hooper
The bacterium Syntrophus aciditrophicus, one of the most extreme-survival organisms ever discovered, has had its genome sequenced.
Syntrophus lives on a diet so austere that it exists on the brink of energetic death. The genes now discovered making up its genome are providing clues as to how it survives, and might even improve the efficiency by which we can make hydrogen from waste materials, the researchers say.
Robert Gunsalus at the University of California, Los Angeles, US, and colleagues, identified 3169 genes in Syntrophus. The bacterium performs a key part of the global carbon cycle by breaking down fatty acids in organic matter – a very limited diet consumed by almost no other organisms. To do this it needs genes that can participate in thermodynamically unfavourable reactions known as reverse electron transport.
Most organisms use oxygen to help breakdown organic compounds for energy use. In this process, organic compounds are chemically oxidised, and the electrons produced in the reaction are used to drive the production of the energy-storage compound ATP.
Syntrophus lives in an anaerobic (non-oxygen) environment, where such a key reaction is impossible. Instead, the flow of electrons occurs in the opposite direction – reverse electron transport – through a reaction that produces hydrogen and formate, which actually requires energy. Without the "help" of other types of bacteria, which consume the hydrogen and formate and provide energy in return, Syntrophus could not survive.
Gunsalus's team found several genes that appear to participate in this process, and they hope to gain a better understanding of the mechanism. “If we can understand such 'syntrophic metabolism', we may be able to increase the amount of hydrogen that can be made from waste materials, and hopefully make biohydrogen production a reality,” says Gunsalus.
Journal reference: Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.0610456104)
