Chickens, Chlorine and Campylobacter: New insights into the redox biology of the most prevalent food-borne pathogen

一些细菌进入我们吃的食物中，导致食物中毒。其中一些细菌很常见，但通常会在烹饪过程中被杀死。当鸡肉没有被正确煮熟时，其中一种被称为空肠弯曲杆菌的细菌就会成为一个特别的问题。它通常生活在鸡的肠道中，对人无害，但会引起严重的腹泻，虽然通常不会危及生命，但会对下班时间造成相当大的影响，在某些情况下可能会导致严重的并发症。通过详细了解这种细菌与宿主相互作用并在食物链中生存的方式，我们可能能够在人类摄入之前阻止定植或提高对细菌的杀灭。我们对空肠弯曲菌的一种特殊性质感兴趣，我们认为这是一个可以利用的弱点--它对氧气非常敏感，很容易被过氧物和次氯酸盐等“活性”氧和氯物种杀死。然而，我们并不完全理解这种情况是如何发生的。在这个项目中，我们将研究次氯酸盐对蛋白质的影响以及这种损伤是如何修复的。我们还将研究当细菌暴露在次氯酸盐中时，基因表达是如何变化的，并试图找出它们如何“感觉”这种化学物质的存在。这些结果应该能让我们更好地了解细菌对氧化损伤的反应方式，这可以在未来被利用来改善食物链干预措施，并为有关使用此类治疗的政策决策提供信息。

Some bacteria get into the food that we eat and cause food-poisoning. Some of these bacteria are quite common but are usually killed during cooking. When chicken meat is not cooked properly, one of these types of bacteria, called Campylobacter jejuni, is a particular problem. It normally lives harmlessly in the intestines of chickens but in humans causes severe diarrohea, which although not usually life-threatening, causes considerable impacts on time off work and in some cases can lead to serious complications. By understanding in detail the way in which this bacterium interacts with its hosts and survives in the food-chain we may be able to stop colonisation or improve killing of the bacteria before human ingestion. We are interested in a specific property of C. jejuni that we think is a vulnerability that can be exploited - it is very sensitive to oxygen and is easily killed by "reactive" oxygen and chlorine species like peroxides and hypochlorite. However, we don't fully understand how this occurs. In this project we will be investigating the effects of hypochlorite on proteins and how this damage is repaired. We will also study how gene expression is changed when the bacteria are exposed to hypochlorite and try to find out how they can "sense" the presence of this chemical. The results should allow us to get a better knowledge of the way in which the bacterium responds to oxidative damage, which could be exploited in future to improve food-chain interventions and to inform policy decisions about the use of such treatments.