太空生活对人是一个极大的挑战。宇航员不仅要应付失重、辐射等外部问题,事实上,他们还要防肚子里的“虫子”——寄生在人体肠道内的微生物——作乱。他们有理由担心,在太空中呆的时间一长,这些微生物或许会背叛他们。众所周知,在人体肠道内,寄生着大量的微生物,单从数量而言,是人体细胞的10倍之多。其中很多对我们的健康至关重要,比如帮助消化食物,制造人体必需的营养素,监护免疫系统等等。当宇航员飞往太空时,它们当然也搭便车去太空“旅行”了。可是,这些微生物在太空微重力的环境下表现如何,这一点过去被科学家极大地忽视了。譬如,最近的几项研究表明,寄生在肠道内的一种会导致食物中毒的细菌沙门氏杆菌,在太空中呆 Space life is a great challenge to people. Astronauts not only have to deal with external problems such as weight loss and radiation, but actually they also need to prevent “bugs” in their belly - microorganisms that are parasitic in the human gut. They have reason to fear that these microorganisms may betray them for a long time in space. As we all know, in the human intestine, parasitic with a large number of microorganisms, the number alone, is 10 times the number of human cells. Many of them are crucial to our health, such as helping to digest food, making nutrients that are essential to the body, guarding the immune system and more. When astronauts flew to space, of course, they also hitchhiking to space “travel”. However, how these microbes behaved in space-microgravity was largely overlooked by scientists. For example, several recent studies have shown that a bacterium Salmonella typhimurium, which causes food poisoning in the gut, stays in space