詼諧的語言，生動的內容一分鐘快速掌握科技最新動態(tài)

>>本期節(jié)目音頻下載<<

Life on Earth requires six basic ingredients—carbon, hydrogen, nitrogen, oxygen, sulfur and phosphorus. Those six elements are the building blocks for DNA and RNA, along with proteins and fats. Which means they're essential for life—as we know it. But it might be time to update that list. Because scientists have found a bacterium that can do without phosphorus—live on arsenic instead.
地球上的生命體需要六種基本元素——碳、氫、氮、氧、硫和磷。這六種元素以及脂肪和蛋白質是DNA和RNA的構成要素，也就是說，和我們知道的一樣，它們是生命體所必須的。但也許是時候更新這份必需元素目錄了，因為科學家們發(fā)現(xiàn)一種細菌會用砷來代替磷，不需要磷也可生存。

The researchers had a hunch a bug like this might exist, because arsenic has some chemical properties in common with phosphorus. So they collected mud from California's Mono Lake, where the waters are naturally salty, and laced with arsenic. Back in the lab, they cultured microbes from that mud. But instead of adding phosphorus to the cultures to help the bugs grow, they added varying levels of arsenic.
因為砷和磷有一些相同的化學特性，研究人員早有預感有這種細菌存在。因此他們從加利福尼亞的莫諾湖收集了一些泥土。莫諾湖水天然帶咸并含砷?；氐綄嶒炇液?，研究人員開始培養(yǎng)泥土中的微生物。但是他們加進去幫助微生物生長的元素并不是磷，而是不同分量的砷。

One bacterial strain continued to thrive. And tests confirmed that the organisms compensated for the lack of phosphorus by building their DNA with arsenic instead. The research appears in the journal Science.
一種細菌在這種情況下繼續(xù)繁殖，而檢測證實這種生命用砷代替了缺乏的磷合成了它們的DNA。這項發(fā)現(xiàn)刊登在《科學》雜志上。

This is the first known life form that seems to be able to swap out one of life's fundamental building blocks with another element. So for astrobiologists hunting for life in space, don’t rule out places filled with poison.
這是人們發(fā)現(xiàn)的第一種可以用其他元素取代生命基本構成要素的生物。因此那些在太空尋找生命的天體生物學家們，可不要忽略了那些充滿毒藥的地方哦！:P

點擊進入?yún)⑴c科學60秒查看背景資料和單詞總結>>>


聲明：音視頻均來自互聯(lián)網(wǎng)鏈接，僅供學習使用。本網(wǎng)站自身不存儲、控制、修改被鏈接的內容。"滬江英語"高度重視知識產權保護。當如發(fā)現(xiàn)本網(wǎng)站發(fā)布的信息包含有侵犯其著作權的鏈接內容時，請聯(lián)系我們，我們將依法采取措施移除相關內容或屏蔽相關鏈接。