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.
【视听版科学小组荣誉出品】
ward off tricky drawback thick and thin devious
每个坏人都有他的致命弱点，显微镜下的恶棍也不例外。想不受这些坏家伙的伤害，我们就要找到它的弱点。现在研究弓形体寄生虫的科学家们觉得这项工作已经完成了。他们在《全国科学院学报》上刊登了研究结果 弓形体寄生虫和疟疾寄生虫很像。因此研究人员工作的重点就是找到抑制这些流氓们繁殖的途径。这些寄生虫很难消灭，因为我们很难预料它们的繁殖方式。它们有时候会繁殖下一代，有时候则只是复制基因，直到时机成熟才将一大群子子孙孙打包送出去。 这种灵活的繁殖方式有优点也有缺点：就算是寄生虫想用不同方式或者想在不同时间分开染色体进行复制，它们都必须跟踪记录自己的染色体信息。现在，科学家们找到了一种结构，它可以在各种恶劣条件下将寄生虫的DNA保存在一个整齐的捆束里面。如果找到一种可以打破这个捆束的药物，我们就可以破坏寄生虫的如意算盘咯。 thick and thin 任何时候 devious ['di:vjəs] adj. 迂回的, 曲折的；不光明正大的, 不坦诚的, 狡猾的 ward off v. 避开,挡住 tricky ['trɪki:] adj. (形势、工作等)复杂的, 棘手的；狡猾的, 诡计多端的；机警的;足智多谋的；微妙的;难处理的