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Bacteria Can Be Resistant¹ to Brand-New Antibiotics³

谁在对抗最新的抗生素

Perhaps the chief poster child of antibiotic² resistance is methicillin-resistant Staphylococcus aureus, or MRSA. The bacterium⁴ is impervious⁵ to a suite⁶ of antibiotics, and can cause blood infections, pneumonia…even death. And you'd assume that it developed its namesake resistance to methicillin…by being exposed to methicillin.

也许抗生素耐药性的主要代表就是“耐甲氧西林金黄色葡萄球菌(MRSA)”。这种细菌不受一系列抗生素的影响，并能引发血液感染、肺炎……甚至死亡。你可能会认为它是通过被暴露于甲氧西林，才生出了同名的抗甲氧西林耐药性……

\But that doesn’t seem to be the case. Instead, the culprit for resistance appears to be an earlier, and chemically related antibiotic: penicillin⁷. "We think it's a very early use of penicillin that forced the strains to pick up these mechanisms⁸." Matthew Holden, a molecular⁹ microbiologist at the University of Saint Andrews in Scotland.

但事实并非如此。相反，耐药性的罪魁祸首似乎是更早的、与化学相关的抗生素：青霉素（盘尼西林）。“我们认为是一种较早时期使用的青霉素迫使菌株去提取了这些机制。”苏格兰圣安德鲁斯大学的一名分子微生物学家马修·霍顿说道。

Holden and his team analyzed¹⁰ the genomes of freeze-dried strains of MRSA bacteria, from the 1960s through the '80s. "In effect what we were doing was sort of genomic archaeology¹¹, in looking at the genomes, and comparing the variation and using that information to effectively reconstruct the evolutionary¹² histories."

霍顿和他的团队分析了20世纪60年代到80年代的、经过冷冻干燥处理的MRSA细菌菌株的基因组。“实际上，我们做的有点像基因组考古。通过研究基因组，比较变异并利用这些信息有效地重建进化史。”

What they found was that the Staph bacteria seem to have acquired the methicillin-resistance gene¹³ in the mid-1940s—about 15 years before methicillin even hit the market. And they determined¹⁴ that it was the widespread use of penicillin that led to that adaptation. The results are in the journal Genome Biology.

他们发现，葡萄球菌似乎是在20世纪40年代中期获得了“抗甲氧西林耐药性”的基因——大约在甲氧西林进入市场的15年前。他们断定是青霉素的广泛使用导致了这种适应性。该研究结果发表在《基因生物学》杂志上。

Methicillin was introduced in the U.K. in 1959. Less than a year later, resistance was first reported—resistance that it appears now was already baked into the staph strains. Looking ahead, Holden says we'd do well to vigilantly¹⁵ monitor the genetics of circulating strains—to find out which bugs¹⁶ may be armed to battle our newest antibiotics as soon as they’re developed.

英国于1959年引入了甲氧西林。不到一年，就第一次报道出了抗药性——一种似乎现在已经进入了葡萄球菌菌株的耐药性。霍顿表