Every villain has his Achilles' heel. And microscopic scoundrels are no exception. The challenge for those who wish to ____1____ microbial bad guys is to identify that weak spot. Now, scientists studying the toxoplasmosis parasite think they’ve done just that. They share the secret in the Proceedings of the National Academy of Sciences.
The toxo parasite is similar to the one that causes malaria. So finding a way to prevent these rogues from reproducing is high on researchers’ to-do lists. The bugs are ____2____ to take down, in part because they’re unpredictable in the way they multiply. Sometimes they get in and get busy making babies. Other times they copy their chromosomes but hold off parceling them out to their army of offspring until the time is right.
This flexibility has benefits, but it also has a ____3____: the parasites have to keep track of their chromosomes…even as they change their minds about how and when to divvy them up. Now scientists have discovered a structure…unique to these parasites…that keeps their DNA in a tidy bundle through ____4____. Find a drug that breaks that bundle packet, and we could destroy these parasites’ ____5____ plans.
【視聽版科學(xué)小組榮譽(yù)出品】
ward off tricky drawback thick and thin devious
每個(gè)壞人都有他的致命弱點(diǎn)，顯微鏡下的惡棍也不例外。想不受這些壞家伙的傷害，我們就要找到它的弱點(diǎn)?，F(xiàn)在研究弓形體寄生蟲的科學(xué)家們覺得這項(xiàng)工作已經(jīng)完成了。他們?cè)凇度珖茖W(xué)院學(xué)報(bào)》上刊登了研究結(jié)果 弓形體寄生蟲和瘧疾寄生蟲很像。因此研究人員工作的重點(diǎn)就是找到抑制這些流氓們繁殖的途徑。這些寄生蟲很難消滅，因?yàn)槲覀兒茈y預(yù)料它們的繁殖方式。它們有時(shí)候會(huì)繁殖下一代，有時(shí)候則只是復(fù)制基因，直到時(shí)機(jī)成熟才將一大群子子孫孫打包送出去。 這種靈活的繁殖方式有優(yōu)點(diǎn)也有缺點(diǎn)：就算是寄生蟲想用不同方式或者想在不同時(shí)間分開染色體進(jìn)行復(fù)制，它們都必須跟蹤記錄自己的染色體信息。現(xiàn)在，科學(xué)家們找到了一種結(jié)構(gòu)，它可以在各種惡劣條件下將寄生蟲的DNA保存在一個(gè)整齊的捆束里面。如果找到一種可以打破這個(gè)捆束的藥物，我們就可以破壞寄生蟲的如意算盤咯。 thick and thin 任何時(shí)候 devious ['di:vj?s] adj. 迂回的, 曲折的；不光明正大的, 不坦誠的, 狡猾的 ward off v. 避開,擋住 tricky ['tr?ki:] adj. (形勢(shì)、工作等)復(fù)雜的, 棘手的；狡猾的, 詭計(jì)多端的；機(jī)警的;足智多謀的；微妙的;難處理的