文学创作策略大本营2:自由,平等,友爱。

《The Emperor of All Maladies: A

2021-03-11  本文已影响0人  游文影月志

Cisplatin--short for cis-platinum--was a new drug forged out of an old one. Its molecular structure, a central planar platinum atom with four "arms" extending outward, had been described back in the 1890s. But chemists had never found an application for cisplatin: the beautiful, satisfyingly symmetric chemical structure had no obvious human use. It had been shelved away in the laboratory in relative obscurity. No one had bothered to test its biological effects.

In 1965, at Michigan State University, a biophysicist, Barnett Rosenberg, began to investigate whether electrical currents might stimulate bacterial cell division. Rosenberg devised a bacterial flask through which an electrical current could be run using two platinum electrodes. When Rosenberg turned the electricity on, he found, astonishingly, that the bacterial cells stopped dividing entirely. Rosenberg initially proposed that the electrical current was the active agent in inhibiting cell division. But the electricity, he soon determined, was merely a bystander. The platinum electrode had reacted with the salt in the bacterial solution to generate a new growth-arresting molecule that had diffused throughout the liquid. That chemical was cisplatin. Like all cells, bacteria need to replicate DNA in order to divide. Cisplatin had chemically attacked DNA with its reactive molecular arms, cross-linking and damaging the molecule irreparably, forcing cells to arrest their division.

顺铂,顺式-二氯二氨合铂(II) 的简称,是一种改造而来的新药。早在19世纪90年代就有人描述了它的分子结构:中央一个铂原子,四周有四个向外延伸的“臂”。但是化学家并没有发现它的用途,这种美丽的,令人满意的对称的化学结构对人类没有什么明显的使用价值。它被默默无闻地搁置在实验室里,没有人愿意去测试它的生物学效应。

1965年,一个密歇根州立大学的生物物理学家 Barnett Rosenberg 开始研究电流是否能够刺激细菌分裂。Rosenberg 设计了一种可以利用两个铂电极通电的细菌瓶。当 Rosenberg 打开电源时,他惊讶地发现细胞分裂完全停止了。起初,他以为是电流抑制了细胞的分裂。但他很快发现电流仅仅是一个局外人。铂电极与细菌溶液中的盐发生反应,生成了一种新的抑制生长分子,并扩散到了整个溶液中。这种化学物质就是顺铂。正如所有的细胞一样,细胞需要复制 DNA 才能分裂。而顺铂通过其活性分子臂攻击了 DNA,它与 DNA 交联起来并对其造成了不可逆的损伤,最终迫使细胞停止分裂。

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