科学美国人60秒 早在抗生素出现之前, 刺猬体内就出现了抗药菌(2)

So the big question was, why hedgehogs carry so much mecC MRSA?

因此，最大的问题是，为什么刺猬携带了这么多mecC MRSA呢？

To find out, Larsen went to the library…

为了找出答案，拉森去了图书馆…

…where I came across an old study from the 1960s which showed that a particular fungus¹ in hedgehogs is able to produce a penicillin²-like antibiotic³ that is very similar to methicillin.

在那里，我偶然找到了一项20世纪60年代的旧研究，这项研究展示了刺猬体内的一种特定真菌能够产生一种类似青霉素的抗生素，这种抗生素与甲氧西林非常相似。

So hedgehogs with this particular skin fungus would naturally be exposed to penicillin.

因此，带有这种特殊皮肤真菌的刺猬自然会接触青霉素。

And that could have launched an evolutionary⁵ arms race that drove the hedgehog’s resident bacteria to evolve resistance.

这可能引发了一场进化军备竞赛，促使刺猬体内的细菌进化出抗体。

This was a real eureka moment and led us to hypothesize that wild hedgehogs have been a natural reservoir of mecC MRSA long before penicillin and methicillin came on the market.

当时我们灵光乍现，猜想早在青霉素和甲氧西林在市场上出现之前，野生刺猬一直都是mecC MRSA的天然储备库。

To confirm this suspicion, Larsen and his colleagues screened hedgehogs from Europe and New Zealand and found that hedgehogs in Scandinavia and the UK harbor a heavy load of mecC MRSA.

为了证实这一猜想，拉森和他的同事对来自欧洲和新西兰的刺猬进行了筛查，发现斯堪的纳维亚和英国的刺猬携带大量的mecC MRSA。

And they also found that the fungus carried by those hedgehogs had all the genes⁶ they needed to produce penicillin.

他们还发现，这些刺猬身上的真菌具备一切需要用来制造青霉素的基因。

We then went on and sequenced and analyzed⁷ the genomes of around one thousand mecC MRSA isolates⁸, which showed that they first appeared in hedgehogs in the early 1800s long before we started to use antibiotics⁹ in human and veterinary medicine.

然后，我们继续对大约1000株mecC MRSA分离株的基因组进行测序和分析。结果表明，早在我们开始在人类和兽医中使用抗生素之前，它们就在19世纪初首次出现在刺猬体内。

Now, that doesn’t mean that we should feel free to use antibiotics all over the place, because it’s not our fault, it’s the hedgehogs’.

现在，虽说这不是我们的错，而是刺猬的错，却并不表明我们可以随意使用抗生素。

Because if having antibiotics around encourages bacteria to evolve resistance, taking antibiotics away robs them of their superpower and leaves them a little bit weaker than their non-resistant¹⁰ kin⁴.

因为如果周围有抗生素会促使细菌进化出抗药性，那么撤走抗生素就会剥夺它们的超能力, 这会让让它们变弱，逊于自己的非抗性同类。

It is often very energy consuming to produce the enzymes¹¹ that inactivate¹² the antibiotics.

生产使抗生素失活的酶通常是非常耗能的。

This means that resistant bacteria will often be outcompeted by susceptible¹³ bacteria in periods when they are not exposed to antibiotics.

这意味着，在不接触抗生素的时期，耐药细菌往往会被易感菌击败。

So if we really want to show MRSA no mercy, we should keep the methicillin to a minimum.

因此，如果我们真的想对MRSA痛下杀手，我们应该将甲氧西林的用量保持在最低水平。

And maybe keep at least a quills-length away from Scandinavian hedgehogs.

也许至少与斯堪的纳维亚的刺猬保持一根刺的距离。

For Scientific American’s 60-Second Science, I’m Karen Hopkin.

谢谢大家收听科学美国人——60秒科学。我是凯伦·霍普金。

1 fungus   

n.真菌，真菌类植物

参考例句：

• Mushrooms are a type of fungus.蘑菇是一种真菌。
• This fungus can just be detected by the unaided eye.这种真菌只用肉眼就能检查出。

2 penicillin   

n.青霉素，盘尼西林

参考例句：

• I should have asked him for a shot of penicillin.我应当让他给我打一针青霉素的。
• Penicillin was an extremely significant medical discovery.青霉素是极其重要的医学发现。

3 antibiotic   

adj.抗菌的；n.抗生素

参考例句：

• The doctor said that I should take some antibiotic.医生说我应该服些用抗生素。
• Antibiotic can be used against infection.抗菌素可以用来防止感染。

4 kin   

n.家族，亲属，血缘关系；adj.亲属关系的，同类的

参考例句：

• He comes of good kin.他出身好。
• She has gone to live with her husband's kin.她住到丈夫的亲戚家里去了。

5 evolutionary   

adj.进化的；演化的，演变的；[生]进化论的

参考例句：

• Life has its own evolutionary process.生命有其自身的进化过程。
• These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。

6 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

7 analyzed   

v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析

参考例句：

• The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
• The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》

8 isolates   

v.使隔离( isolate的第三人称单数 )；将…剔出（以便看清和单独处理）；使（某物质、细胞等）分离；使离析

参考例句：

• The transformer isolates the transistors with regard to d-c bias voltage. 变压器可在两个晶体管之间隔离直流偏压。 来自辞典例句
• In regions with certain isolates of TRV, spraining is more prominent. 在具有TRV某些分离物的地区，坏死是比较显著的。 来自辞典例句

9 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

10 resistant   

adj.(to)抵抗的，有抵抗力的

参考例句：

• Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
• They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。

11 enzymes   

n. 酶，酵素

参考例句：

• It was said that washing powders containing enzymes remove stains more efficiently. 据说加酶洗衣粉除污更有效。
• Among the enzymes which are particularly effective are pepsin, papain. 在酶当中特别有效的是胃朊酶、木瓜酶。

12 inactivate   

v.使…不活跃

参考例句：

• We put bacteria in an environment at low temperature to inactivate them.我们将细菌置於低温的环境中使之失去活性。
• Food processing destroys some nutrients,but can also inactivate toxins and increase the availability of other nutrients.食物加工破坏一些营养物质，但也可以灭活毒素，并增加其他营养物质的可用性。

13 susceptible   

adj.过敏的，敏感的；易动感情的，易受感动的

参考例句：

• Children are more susceptible than adults.孩子比成人易受感动。
• We are all susceptible to advertising.我们都易受广告的影响。