Kinne-Saffran E, Kinne R K
Max-Planck-Institut für molekulare Physiologie, Dortmund, Germany.
Am J Nephrol. 1999;19(2):290-4. doi: 10.1159/000013463.
In 1828, Friedrich Wöhler, a German physician and chemist by training, published a paper that describes the formation of urea, known since 1773 to be a major component of mammalian urine, by combining cyanic acid and ammonium in vitro. In these experiments the synthesis of an organic compound from two inorganic molecules was achieved for the first time. These results weakened significantly the vitalistic hypothesis on the functioning of living cells, although Wöhler, at that time, was more interested in the chemical consequences of isomerism than in the philosophical implications of his finding. However, the chemical synthesis observed by Wöhler does not represent the reaction which is employed in the mammalian liver for urea synthesis. The mechanism of this process was elucidated by the German physician Hans A. Krebs and his medical student Kurt Henseleit in 1932 and was shown to include the ornithine cycle. This 'urea cycle' is only observed in living cells; this apparently vitalistic phenomenon is caused by the compartmentalization of the various enzymatic reactions in mitochondria and cytosol, respectively.
1828年，受过医学和化学专业训练的德国医生弗里德里希·维勒发表了一篇论文，描述了通过在体外将氰酸和铵结合来形成尿素的过程。自1773年以来，尿素就被认为是哺乳动物尿液的主要成分。在这些实验中，首次实现了由两个无机分子合成有机化合物。这些结果极大地削弱了关于活细胞功能的活力论假说，尽管当时维勒对异构现象的化学后果比对他这一发现的哲学意义更感兴趣。然而，维勒观察到的化学合成并不代表哺乳动物肝脏中用于合成尿素的反应。1932年，德国医生汉斯·A·克雷布斯和他的医学生库尔特·亨泽莱特阐明了这一过程的机制，并证明其包括鸟氨酸循环。这种“尿素循环”只在活细胞中观察到；这种明显的活力论现象是由线粒体和细胞质中各种酶促反应的区室化分别导致的。
