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In a remote lake in California, scientists have discovered a form of bacteria that could hold the secret to life on other planets. |
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The tiny and remarkable organism can thrive on arsenic, an element that has up to now been considered poisonous. |
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The finding dramatically expands both the commonly-held idea of how life is sustained and the range of environments in which it might be found across the universe. |
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科學家在加州一座偏遠的湖泊發現了一種細菌，可能藏有外星球是否有生物存在的秘密。這種微小而非凡的生物賴以維生的元素，竟是我們向來認為有毒的砷。這項發現大幅擴展了我們對生命如何維繫的認知，以及宇宙中哪些環境可能發現有生命存在。 |
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The announcement of the discovery was made by NASA-funded researchers Thursday. |
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美國太空總署資助的研究人員在週四宣布了這項發現。 |
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"Life as we know it requires particular chemical elements and excludes others," Arizona State University researcher Ariel Anbar said in a news release. |
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"But are those the only options? How different could life be?" |
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亞利桑那州立大學艾里爾．安巴在一份新聞稿中指出：「就我們所知，生物需要特定的化學元素，並且會排除其他元素。可是這些元素是唯一的選擇嗎？生物可能多麼地不同呢？」 |
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The bacterium is known as strain GFAJ-1 of the Halomonadaceae family of Gammaproteobacteria. |
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It was found in sediment taken from California's Mono Lake. |
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The lake's water and surrounding area are rife with high levels of naturally occurring arsenic. |
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這種細菌是丙型變形菌綱鹽單胞菌科的 GFAJ-1 菌株，是在加州摩諾湖沉積物裡發現的。這座湖泊的湖水和周遭地區都富含大量自然生成的砷。 |
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Scientists were able to grow the microbes from the lake with only small amounts of phosphorus. |
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The element is an essential nutrient in the biomolecules of naturally occurring bacteria. |
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科學家僅利用微量的磷，就得以培養湖中的微生物。在自然生成細菌的生物分子中，磷是不可或缺的營養素。 |
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"We've discovered an organism that can substitute one element for another," said NASA scientist Felisa Wolfe-Simon. |
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"Nothing should have grown. Put your plant in the dark, it doesn't grow." |
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「我們發現了一種生物，能夠以一種元素取代另一種元素，」太空總署科學家費莉莎．沃夫賽門表示：「原本應該沒有生物能夠生長得出來。把植物放在黑暗裡，植物是不會生長的。」 |
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Not only did the bacterium grow, but it also incorporated the arsenic molecules into its DNA, in place of phosphorus, she said. |
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她說，但這種細菌不但能夠生長，還以砷分子取代磷而納入本身的 DNA 裡。 |
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"We've cracked open the door to what's possible elsewhere in the universe," Wolfe-Simon said during a press conference Thursday. |
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「我們已經打開了一扇門，一窺宇宙中的其他地方可能存在什麼現象，」沃夫賽門在週四的一場記者會上表示。 |
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Online chatter had reached a fever pitch by Thursday ahead of the news conference, which NASA promised would "discuss an astrobiology finding that will impact the search for evidence of extraterrestrial life." |
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在記者會舉行之前，網路上的傳言在週四已達到了極度狂熱的程度，因為太空總署宣稱這場記者會將「討論一項天體生物學的發現，將會影響外星生物證據的搜尋工作。」 |
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