Understanding the ecology of Listeria and its interactions with microbiomes in food processing facilities to inform biocontrol strategies

英国每年有超过100万例食物中毒，估计经济负担为15亿英镑。李斯特菌是引起食物中毒的五大原因之一。这是一个特别的问题，与冷藏食品，如未经巴氏消毒的牛奶，软奶酪，沙拉和许多即食，冷藏食品。L.单核细胞增多症可在孕妇、老年人和新生儿等弱势群体中引起脑膜炎、死产和流产。在欧洲，2014年报告了2161例确诊病例，比前一年增加了30%。与其他食源性疾病相比，李斯特菌病的发病率相对较低，但由于其高达30%的死亡率，该疾病与重大的公共卫生和经济负担相关。该项目将提供影响李斯特菌在食品加工环境中存活的因素的知识库，其中李斯特菌能够在许多场所定植，特别是潮湿，潮湿的条件如排水沟，地板、清洗区和食品处理表面。尽管有强大的清洁和消毒程序，李斯特菌属。坚持在环境中。虽然我们对李斯特菌的遗传学和持久性了解很多。来源于临床样品，李斯特菌属（Listeria spp.）存在于食品工厂环境中的李斯特菌的遗传组成还没有被研究到相同的程度，并且在我们对以下的理解中仍然存在显著的差距：（a）在食品加工厂中发现的李斯特菌菌株的遗传组成和（B）这些李斯特菌属物种如何在食品加工厂环境中被发现。与工厂微生物群落的不同细菌物种相互作用。这项建议将填补我们知识上的这些空白。我们将与食品加工部门密切合作，分析从食品加工厂内不同类型表面获得的拭子。然后将这些样本用于鉴定李斯特菌属。和相关的工厂细菌。将确定整个基因组序列，以通过加工厂的不同部分追踪病原体，这将为工厂内的污染途径和特定李斯特菌的持久性提供独特的见解。在工厂的特定区域。为了调查工厂环境中细菌的完整多样性，我们将使用先进的基于DNA的指纹识别方法来识别不同工厂场所中存在哪些其他类型的细菌，以及这些细菌与特定位置李斯特菌菌株的存在/不存在之间是否存在联系。全基因组序列数据还将为深入了解与生物膜形成、杀菌剂抗性以及与其他细菌的复杂群落相关的基因提供帮助。强有力的证据表明，李斯特菌能够在环境中存活，因为它能够形成生物膜（细菌在固体表面上作为群落生长）。因此，我们将确定李斯特菌分离株形成生物膜的能力，无论是单独的还是在存在从工厂表面分离的其他细菌的情况下，以评估这些细菌如何影响李斯特菌属的生物膜形成。和他们在工厂的坚持。这些生物膜研究将在一个“模型工厂”中进行检查，我们将在IFR实验室中建立一个模型工厂，以重建不同的表面并模拟工厂的环境条件。为了开展这项多学科计划，我们组建了一个由食品行业技术专家和学术研究科学家组成的合作团队。这项研究将提供更好的了解李斯特菌的行为和生存。在食品加工环境中。我们的最终目标是提供详细，广泛的知识，为工业开发减少李斯特菌的新方法提供信息。在食品加工环境中。这些改进的方法将作为“最佳实践”与更广泛的冷冻食品行业分享，最终带来显著的健康/经济效益。

There are over one million cases of food poisoning in the UK each year with an estimated economic burden of £1.5 billion. Listeria monocytogenes is one of the five major causes of food poisoning. It is a particular problem with chilled foods such as unpasteurised milk, soft cheeses, salads and many of the ready-to-eat, chilled foods. L. monocytogenes can cause meningitis, still births and abortion, in vulnerable groups including pregnant women, the elderly, and the neonates. In Europe, 2161 confirmed cases of listeriosis were reported in 2014, a rise of 30% on the previous year. In comparison to other food-borne diseases the incidence of listeriosis is relatively low, however the disease is associated with significant public health and economic burdens because of its high mortality rate of up to 30%.This project will provide a knowledge base of factors that influence survival of Listeria in the food processing environment where it is able to colonise many sites, particularly damp, moist conditions such as drains, floors, wash areas and food handling surfaces. Despite robust cleaning and sanitising procedures, Listeria spp. persist in the environment. While we know a great deal about the genetics and persistence of Listeria spp. originating from clinical samples, Listeria spp. present in food factory environments have not been studied to the same degree, and there remains a significant gap in our understanding of: (a) the genetic makeup of Listeria strains that are found in food processing factories and (b) how these Listeria spp. interact with diverse bacterial species of the factory microbial communities. This proposal will address these gaps in our knowledge. We will work closely with the food processing sector and analyse swabs obtained from different types of surfaces within food processing factories. These samples will then be used to identify both the Listeria spp. and associated factory bacteria. The whole genome sequence will be determined to track the pathogen through different parts of the processing factory and this will provide unique insight into routes of contamination within the factory and the persistence of particular Listeria spp. in specific areas of the factory. To survey the complete diversity of bacteria in the factory environment we will use advanced DNA based fingerprinting methods to identify which other types of bacteria are present in different factory sites and if there is a connection between these bacteria and presence/absence of the Listeria strains at a particular location. Whole genome sequence data will also provide insight into the genes associated with biofilm formation, biocide resistance and association as complex communities with other bacteria.Strong evidence suggests that Listeria persists in the environment because of its ability to form biofilms (where bacteria grow as communities on solid surfaces). We will therefore determine the ability of the Listeria isolates to form biofilms, both individually and also in the presence of other bacteria isolated from the factory surfaces to assess how these bacteria impact biofilm formation by Listeria spp. and their persistence in the factory. These biofilm studies will be examined in a 'model factory' that we will set up in the IFR lab to recreate diverse surfaces and simulate factory environmental conditions. To undertake this multidisciplinary programme we have assembled a collaborative team of technical experts from the food industry and academic research scientists. This research will provide improved understanding of the behaviour and survival of Listeria spp. in food processing environments. Our ultimate aim is to provide detailed, extensive knowledge to inform the industrial development of new methods to reduce Listeria spp. levels in the food processing environment. These improved methods will be shared as 'best practice' with the wider chilled food industry, eventually leading to significant health / economic benefits.