SCIENTISTS CHALLENGE THINKING ABOUT LIFE AFTER TRANSFORMING CHEMICALS INTO LIVING ORGANISM

2010 年05月21日 05:59 AM

SCIENTISTS CHALLENGE THINKING ABOUT LIFE AFTER TRANSFORMING CHEMICALS INTO LIVING ORGANISM By Clive Cookson Science Editor


Scientists have turned inanimate chemicals into a living organism in an experiment that raises profound questions about the essence of life.Craig Venter, the US genomics pioneer, announced last night that scientists at his laboratories in Maryland and California had succeeded in their 15-year project to make the world's first “synthetic cells” – bacteria called Mycoplasma mycoides.“We have passed through a critical psychological barrier,” Dr Venter told the Financial Times.

“It has changed my own thinking, both scientifically and philosophically, about life and how it works.”The bacteria's genes were all constructed in the laboratory “from four bottles of chemicals on a chemical synthesiser, starting with information on a computer,” he said. The research – published online by the journal Science – was hailed as a landmark by many independent scientists and philosophers. Julian Savulescu, ethics professor at Oxford University, said: “This is a step towards . . . creation of living beings with capacities and natures that could never have naturally evolved.”

The synthetic bacteria have 14 “watermark sequences” attached to their genome – inert stretches of DNA added to distinguish them from their natural counterparts. They behaved and divided in lab dishes like natural bacteria. M mycoides was chosen as a simple microbe with which to develop and prove the technology.

It has no immediate application.But scientists at the J Craig Venter Institute and Synthetic Genomics, the company funding their research, intend to move on to more useful targets that may not exist in nature. They are particularly interested in designing algae that can capture carbon dioxide from the air and produce hydrocarbon fuels. Last year Synthetic Genomics signed a $600m agreement with ExxonMobil to make algal biofuels. “We have looked hard at natural algae and we can't find one that can make the fuels we want on the scales we need,” Dr Venter said.

美国科学家造出“合成细菌” 英国《金融时报》科学编辑 克莱夫·库克森 报道 科学家已把无生命的化学物质转化为有生命的有机体，这项实 验对生命的本质提出了意义深远的问题。美国基因组学先驱克莱格·凡特(Craig Venter)昨天宣布，在他位于马里兰州和加州的实验室，科研人员在其为期15年的研究项目中，已成功制造出全球首个“合成细胞”，一种称为丝状支原体 的细菌。“我们穿越了一道关键的心理障碍，”凡特对英国《金融时报》表示。“这在科学和哲学两个层面上改变了我自己对生命及其机理的思 索。”他表示，这一人造细菌的基因均在实验室内构建，“从电脑上的信息开始，使用四瓶化学物质和一台化学合成装置来构建的。”《科学》期刊在网上发表了这项研究。它被许多独立科学家和哲学家誉为一个标志性突破。英 国牛津大学(Oxford University)的伦理学教授朱利安·萨乌莱斯(Julian Savulescu)表示：“此举向创造具有能力的生物和构建永远不可能自然进化的‘自然界'迈出了一步。”这种合成的细菌有14个“水印 序列”附在其基因组上，添加这些惰性的DNA延伸，是为了使其有别于同类的天然细菌。在培养皿中，合成细菌的行为（包括分裂）就像天然细菌一样。之所以选 择丝状支原体，是因为这是一种简单的微生物，便于开发和验证相关技术。这种技术眼下没有实际用途。


但克莱格·凡特研究所(J Craig Venter Institute)和合成基因组公司(Synthetic Genomics)的科研人员有意向前推进，瞄准自然界可能不存在的更有用的目标。他们特别感兴趣的是，设计能够从空气中捕捉二氧化碳、然后产生碳氢化合 物燃料的藻类。合成基因组公司资助这项研究。

去年，合成基因组公司与埃克森美孚(ExxonMobil)签署了一项6亿美元的协议，旨在制 造藻类生物燃料。“我们对天然藻类进行了大量研究，但找不到能以我们需要的规模、产生我们想要的燃料的藻类，”凡特表示。