Scientists have isolated a unique molecular pattern that might one day enable a 'stress vaccine' to exist for real – and they found it hidden inside a bacterium that thrives in dirt.

　　科学家分离出一种独特的分子模式，将来可能将“压力疫苗”变成现实，他们发现这种分子隐藏在一种在泥土中大量存在的细菌中。

　　Mycobacterium vaccae is a non-pathogenic bacterium that lives in soil, and has shown considerable promise in health research; now, a new study may have finally figured out why.

　　母牛分枝杆菌是一种无毒细菌，存在于土壤中，在健康研究方面有相当大的潜力，现在一项新的研究最终给出了原因。

　　The findings suggest that a specific kind of fat inside M. vaccae could be why exposure to this seemingly beneficial bacterium in ground soil may be good for us.

　　研究结果表明可能就是母牛分枝杆菌中一种特定的脂肪使接触这种看似有益的土壤细菌对我们有好处的。

　　This work ties in with the idea of "old friends", a hypothesis that claims humans co-evolved with a bunch of useful microorganisms, and losing those ties in the modern environment has led to an increase in allergic and autoimmune diseases.

　　这种作用与“老朋友”的说法有关，是一种假设，认为人类和一些有益微生物共同进化。而在现代环境中失去这种联系导致了过敏性和自身免疫性疾病的增加。

　　"The idea is that as humans have moved away from farms and an agricultural or hunter-gatherer existence into cities, we have lost contact with organisms that served to regulate our immune system and suppress inappropriate inflammation," says neuroendocrinologist Christopher Lowry.

　　神经内分泌学家Christopher Lowry说：“这个说法就是随着人类从农场和以农业或狩猎采集为生的生活转移到了城市中，我们失去了和微生物的联系，而这些微生物能调节免疫系统、抑制不良炎症。”

　　"That has put us at higher risk for inflammatory disease and stress-related psychiatric disorders."

　　“这使我们出现炎症和患与压力有关的精神障碍的风险增高。”

　　Lowry has been researching M. vaccae for years, finding in a previous study that injecting mice with a heat-killed preparation of the bacterium prevented the emergence of stress-induced reactions in the animals.

　　Lowry研究母牛分枝杆菌多年，在此前的一项研究中发现给小鼠注射热休克制备的母牛分枝杆菌会避免动物产生应激反应。

　　But until now, nobody was sure what was it in M. vaccae that could be responsible for such effects.

　　但是，在此之前，还没人能确定母牛分枝杆菌中是什么成分有这种作用。