第十九章 生命的起源
In 1953, Stanley Miller, a graduate student at the University of Chicago, took two flasks—one containing a little water to represent a primeval ocean, the other holding a mixture of methane, ammonia, and hydrogen sulphide gases to represent Earth's early atmosphere—connected them with rubber tubes, and introduced some electrical sparks as a stand-in for lightning. After a few days, the water in the flasks had turned green and yellow in a hearty broth of amino acids, fatty acids, sugars, and other organic compounds. "If God didn't do it this way," observed Miller's delighted supervisor, the Nobel laureate Harold Urey, "He missed a good bet."
1953年，芝加哥大学的研究生斯坦利·米勒拿起两个长颈瓶——一个盛着一点水，代表远古的大海洋，一个装着甲烷、氨和硫化氢的气体混合物，代表地救上早期的大气——然后用橡皮管子把两个瓶子一连，放了几次电火花算做闪电。几个星期以后，瓶子里的水呈黄绿色，变成了营养丰富的汁，里面有氨基酸、脂肪酸、糖以及别的有机化合物。米勒的导师、诺贝尔奖金获得者哈罗德·尤里欣喜万分，说：“我可以打赌，上帝肯定是这么干的。”
Press reports of the time made it sound as if about all that was needed now was for somebody to give the whole a good shake and life would crawl out. As time has shown, it wasn't nearly so simple. Despite half a century of further study, we are no nearer to synthesizing life today than we were in 1953 and much further away from thinking we can. Scientists are now pretty certain that the early atmosphere was nothing like as primed for development as Miller and Urey's gaseous stew, but rather was a much less reactive blend of nitrogen and carbon dioxide. Repeating Miller's experiments with these more challenging inputs has so far produced only one fairly primitive amino acid. At all events, creating amino acids is not really the problem. The problem is proteins.
当时的新闻报道听上去让人觉得，你只要把瓶子好好地晃一晃，生命就会从里面爬出来。时间已经表明，事情根本不是那么简单。尽管又经过了半个世纪的研究，今天我们距离合成生命与1953年的时候一样遥远——更不用说认为我们已经有这等本事。科学家们现在相当肯定，早斯的大气根本不像米勒和尤里的混合气体那样已经为生命的形成作好准备，而是一种根本很不活泼的氮和二氧化碳的混合物。有人用这些更具挑战性的气体重新做了米勒的实验，至今只制造出一种非常原始的氨基酸，无论如何，其实问题不在于制造氨基酸，问题在于蛋白质。
来源:可可英语 http://www.kekenet.com/Article/201805/553926.shtml
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