Developing novel models to understand threats from Vibrio pathogens for safeguarding aquatic food supply under future climates

开发新模型来了解弧菌病原体的威胁，以保障未来气候下的水产食品供应

• 批准号: NE/X010333/1
• 负责人: Charles Tyler
• 金额: $ 10.26万
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX010333%2F1
• 关键词: Developing; novel; models; understand; threats

Climate change, leading to ocean warming, is affecting the frequency, intensity and duration of extreme weather events affecting nearshore ecosystems that will make our UK coastal shellfisheries more vulnerable to new and emerging microbial diseases, and with potentially greater associated human health concerns. When bacteria encounter extreme or unfavourable environmental conditions they enter a state of dormancy to protect themselves, however, they can re-awaken when favourable environmental conditions return. For bacterial pathogens these re-emergent blooms can be hazardous to the environment and in some cases to human health. A major problem in the prevention of bacterial diseases is that dormant cells are not detectable by routine tests making them difficult to study. In this project, we will exploit new approaches to understand the ways (mechanisms) by which dormant bacterial Vibrio cells (our study organism) emerge as active disease-causing pathogens in the environment to provide a springboard for future projects for predicting and preventing Vibrio disease establishment in wild shellfisheries and farmed shellfish, and the protection of human health.Vibriosis is a disease responsible for numerous mass mortality events in managed and wild shellfisheries, and globally Vibrio pathogens are the leading causes of seafood related gastroenteritis in humans. In our coastal waters, sediment and shellfish, Vibrio parahaemolyticus is found during the summer months but is not detected in the winter. It had been assumed that these bacteria die due to the cold-water temperatures, however, we know now that a small proportion enter dormancy in order to survive cooler (winter) conditions. When summer conditions return and, nutrient levels and sea temperatures increase these dormant cells reawaken, growing into bacterial populations that can infect shellfish and cause adverse human health impacts. In this project, we will first detect and quantify Vibrio in its various functional states in relation to environmental abiotic factors in water, sediment, and shellfish from a coastal site in Dorset, England. The cell sorting and staining methods we will apply, will allow us to separate dormant Vibrio cell populations from those that are metabolically active and those that are non-viable. We will then assess the ability to resuscitate the dormant cells collected from the environmental samples through manipulating the salt and temperature to simulate summer conditions and with the addition of sodium lactate (we have shown that lactate can resuscitate Vibrio dormant cells for our laboratory induced dormant cells). We will also test the virulence potential of the resuscitated Vibrio cells derived from our environmental samples through their injection to an established moth larvae disease model. Finally, we will develop analytical protocols (using mass spectrophotometry methods) to determine the fate of lactate in environmental dormant cells and identify metabolism mechanisms as the dormant cells switch to the actively growing cell population. Collectively these studies will be a major step forward in establishing the factors that allow Vibrio cells to emerge from dormancy and establish as a growing population under favourable climate conditions to cause disease. Improving our ability to predict when Vibrio bacterial populations are established will help prevent disease reinfections and avoidance of seasonal epidemics through adoption of mitigation strategies such as depuration of the shellfish, and/or early and/or selective harvesting.

导致海洋变暖的气候变化正在影响影响近海生态系统的极端天气事件的频率，强度和持续时间，这将使我们的英国沿海贝类者更容易受到新的和新兴的微生物疾病的影响，并且可能会引起更多相关的人类健康问题。但是，当细菌遇到极端或不利的环境条件时，它们会进入一个休眠状态以保护自己，但是，当有利的环境条件恢复时，它们可能会重新唤醒。对于细菌病原体，这些重新出现的开花可能对环境有害，在某些情况下可能对人类健康有害。预防细菌疾病的一个主要问题是，通过常规测试无法检测到休眠细胞，因此难以研究。在这个项目中，我们将利用新方法来了解休眠细菌细胞（我们的研究有机体）的方式（机制）作为在环境中引起病原体病原体的活跃病原体的出现，以为未来的项目提供预测和防止野生贝壳和人类疾病的疾病疾病的武器和保护的武器，以预测和预防福利氏病的速度疾病。全球弧菌病原体是人类与海鲜相关的胃炎的主要原因。在我们的沿海水域，沉积物和贝类中，在夏季发现了颤动的溶血性，但在冬季未发现。据认为，这些细菌由于冷水温度而死亡，但是，我们现在知道，为了使凉爽（冬季）条件生存下来，较小的比例会进入休眠状态。当夏季状况恢复时，营养水平和海温会增加这些休眠的细胞，从而成长为可感染贝类并引起人类健康影响的细菌种群。在该项目中，我们将首先检测到其各种功能状态中的弧菌与英格兰多塞特郡沿海地区的水，沉积物和贝类中的环境非生物因素有关。我们将应用的细胞分选和染色方法将使我们能够将休眠的颤音细胞群体与代谢活性和不可行的细胞分离。然后，我们将评估通过操纵盐和温度来模拟夏季条件并添加乳酸钠，从而使从环境样品中收集的休眠细胞复苏的能力（我们已经表明，乳酸可以为我们的实验室诱导的休眠细胞恢复弧菌休眠细胞）。我们还将测试通过注射到已建立的蛾幼虫疾病模型中的环境样品中衍生的复苏弧菌细胞的毒力潜力。最后，我们将开发分析方案（使用质量分光光度法方法）来确定乳酸在环境休眠细胞中的命运，并随着休眠细胞转换为主动生长的细胞群，并鉴定代谢机制。这些研究集体将是建立允许颤音细胞从休眠状态出现并在有利的气候条件下成为不断增长的人口的因素，这将是向前迈出的重要一步。提高我们预测何时建立弧菌细菌种群的能力，将有助于通过采用缓解策略（例如贝壳虫降级，和/或早期和/或选择性收获）来预防疾病的疾病并避免季节性流行病。