Characterization and intervention strategies of Campylobacter jejuni biofilm in a microfluidic "lab-on-a-chip" system

微流体“芯片实验室”系统中空肠弯曲杆菌生物膜的表征和干预策略

• 批准号: RGPIN-2014-05487
• 负责人: Lu, Xiaonan
• 金额: $ 2.11万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=658033
• 关键词: Characterization; intervention; strategies; Campylobacter; jejuni

Campylobacter jejuni is the leading cause of foodborne bacterial gastroenteritis in the developed world, with diarrhea often associated with consumption of undercooked poultry products, drinking water and unpasteurized milk. It is estimated that 1% of Canadian population is affected with campylobacteriosis each year, resulting in significant burden on economy because of lost productivity and the potential for serious medical complications. Residing in a biofilm microenvironment is a critical way for this microaerophilic pathogen to survive and transmit into the food chain in stressful conditions, such as the natural aerobic environment, leading to food poisoning. Biofilm formation allows bacteria to grow and survive, as the surface-attached and matrix-encased bacteria are protected. My overall research program is to understand the behavior of C. jejuni in the environment, food systems and animals, and to develop mitigation strategies to reduce campylobacteriosis. The aim of this research proposal is to use novel approach and advanced technology to characterize C. jejuni biofilms and develop intervention strategies. Our central hypothesis is that natural compounds and synthetic polymers can inhibit C. jejuni biofilm formation driven by environmental and genetic factors. Our specific objectives in the first five-year period are to investigate oxygen condition that promotes C. jejuni biofilm formation, to identify and characterize C. jejuni colonization associated proteins involved in biofilm formation, to identify compounds as either antimicrobials or quorum sensing (QS) signal inhibitors, resulting in less C. jejuni biofilms, and to develop molecularly imprinted polymers (MIPs) as QS capturer to inhibit C. jejuni biofilms. We have established a microfluidic "lab-on-a-chip" platform coupled with biophysical instruments (i.e., confocal micro-Raman spectroscopy and atomic force microscopy) to cultivate and nondestructively characterize C. jejuni biofilms in a natural state. The work will allow us to better understand biofilm as an important vehicle for C. jejuni to survive during transit between hosts and on food products under unfavorable conditions and to further develop effective strategies to reduce biofilm formation. The studies address fundamental questions of bacterial stress, QS, and gene expression, and the knowledge to be generated is therefore of broad biological interest. The development of QS inhibitors and capturers will suggest new ways that food industry to reduce the prevalence of pathogens. For example, MIPs can be grafted onto food contact surfaces to reduce bacterial biofilms. Pharmaceutical company may also be able to design novel antimicrobials based on new target site (i.e., QS) while do not increase bacterial antibiotic resistance. This research has the potential for significant economic benefit to Canadian food producers and public health while increasing fundamental knowledge on bacterial biofilms that may translate to study other pathogens.

空肠弯曲菌是发达国家食源性细菌性胃肠炎的主要原因，腹泻通常与食用未煮熟的家禽产品、饮用水和未经巴氏消毒的牛奶有关。据估计，每年有1%的加拿大人口受到弯曲杆菌病的影响，由于生产力损失和严重医疗并发症的可能性，对经济造成重大负担。这种微需氧病原体在生物膜微环境中生存并在应激条件下（如自然需氧环境）传播到食物链中，导致食物中毒。生物膜的形成允许细菌生长和存活，因为表面附着和基质包裹的细菌受到保护。我的总体研究计划是了解C的行为。该项目旨在加强对环境、食品系统和动物中空肠弯曲菌的监测，并制定减少弯曲菌病的缓解战略。本研究的目的是采用新的方法和先进的技术来表征C。空肠生物膜和制定干预策略。我们的中心假设是天然化合物和合成聚合物可以抑制C。空肠生物膜形成由环境和遗传因素驱动。第一个五年的具体目标是研究促进C.空肠生物膜形成，以鉴定和表征C.空肠定殖相关蛋白参与生物膜形成，以鉴定化合物作为抗菌剂或群体感应（QS）信号抑制剂，导致较少的C.空肠弯曲菌生物膜，并开发分子印迹聚合物（MIPs）作为QS捕获剂，以抑制C.空肠生物膜我们已经建立了与生物物理仪器耦合的微流体“芯片实验室”平台（即，共焦显微拉曼光谱和原子力显微镜）培养和非破坏性地表征C。自然状态下空肠生物膜。这项工作将使我们更好地了解生物膜作为C。空肠在不利条件下在宿主之间和食物产品上的运输期间存活，并进一步开发有效的策略以减少生物膜形成。这些研究解决了细菌应激、QS和基因表达的基本问题，因此所产生的知识具有广泛的生物学意义。QS抑制剂和捕获剂的开发将为食品工业降低病原体的流行提供新的途径。例如，MIP可以接枝到食品接触表面上以减少细菌生物膜。制药公司还可以基于新的靶位点（即，QS），同时不增加细菌的抗生素耐药性。这项研究有可能为加拿大食品生产商和公共卫生带来重大经济效益，同时增加有关细菌生物膜的基础知识，这些知识可能转化为研究其他病原体。