Establishing drivers for the generation and transmission of antimicrobial resistance in the food chain

病原微生物对食品安全和传染病传播构成重大威胁，特别是在抗生素耐药生物(ARO)的传播仍然是一个严重关切的情况下。在环境中选择或维护ARO的驱动因素是这些生物通过食物链传播的重要途径。因此，环境中ARO的发生和存在可能仅仅是由于内源性抗生素的选择，或者在环境中应用抗生素或类似抗生素的化合物造成的。因此，最近的数据显示，导致农药耐药性的遗传因素也会导致抗生素耐药性。尽管有这些证据，但人们对农药暴露的影响以及食物链中常见微生物产生抗菌素耐药性的潜力知之甚少。在这项应用中，我们的总体目标是为农药暴露和AMR生物从环境中转移到食品供应中建立一个机制基础；其中具体目标是：目标1：建立“定植和抗药性”植物模型系统，我们将使用一种易于遗传的模型，该模型将利用受普通农药处理(草甘膦)的相关可食用园艺物种，接种两种与抗菌剂耐药性(KPN)和食源性传播(Eco O157：H7)相关的微生物物种。这个模型系统将被用来参数体内定植的条件，如细菌定植与时间，农药浓度，以诱导适应性的遗传变化。目标2：为了建立农药耐药性的机制基础，将从优化的模型系统中通过全基因组序列分析和转录组(RNA-seq)分析来确定农药暴露后的整体适应性变化。这将建立两者，哪些基因代表突变热点和调控网络被改变，从而促进基因变化的综合网络被定位并与抗生素/农药耐药性表型相关联。目标3：确定农药暴露是否加速了抗菌剂和农药耐药性的获得。利用体内模型，在存在或不存在杀虫剂和外源AMR细菌(如动物粪便)的情况下，将建立焦点物种例如KPN或Eco O157：H7的遗传和表型特性。这将确定对杀虫剂的适应是否可以加速从外源来源获得或水平转移抗性元素。预期的结果将是验证和实施体内植物微生物定植模型，以评估杀虫剂使用在促进微生物和ARO转移方面的贡献。

Pathogenic microorganisms pose a significant threat to food security and in the spread of infectious diseases, particularly where the transmission of antibiotic resistant organisms (ARO) remains a critical concern. The drivers for the selection or maintenance of ARO's within the environment represents an important route for the dissemination of these organisms via the food chain. As such, the occurrence and presence of ARO's in the environment can arise simply as a result of selection by endogenous antibiotics, or the application of antibiotic or antibiotic-like compounds within the environment. As such, recent data reveals that the genetic factors which contribute to pesticide resistance also confer antibiotic resistance. Despite this evidence, little is known about the impact of pesticide exposure and the potential for the development of antimicrobial resistance in common microorganisms found within the food chain. In this application, our overarching aim is to establish a mechanistic basis for pesticide exposure and the transfer of AMR organisms from the environment into the food supply; where the specific aims are to:Aim 1: To establish a "colonisation & pesticide resistance" plant model system, we will use a genetically tractable model, which will exploit a relevant edible horticultural species subject to common pesticide treatment (glyphosate), inoculated with two microbial species associated with antimicrobial resistance (Kpn) and foodborne transmission (Eco O157:H7). This model system will be used to parameterise the conditions of in vivo colonisation such as bacterial colonisation versus time, pesticide concentrations to elicit adaptive genetic changes.Aim 2: To establish the mechanistic basis of pesticide resistance, wholescale adaptive changes after pesticide exposure will be determined from the optimised model system, by both whole genome sequence analysis and transcriptome (RNA-seq) profiling. This will establish both, which genes represent mutational hot-spots and regulatory networks are altered, thus facilitating an integrated network of genetic changes to be mapped and linked to the antibiotic/pesticide resistance phenotype.Aim 3: Determine if pesticide exposure accelerates the acquisition of antimicrobial and pesticide resistance. Using the in-vivo model, the genetic and phenotypic properties of the focal species e.g, Kpn or Eco O157:H7 will be established in the presence or absence of pesticides and exogenous AMR bacteria e.g. animal manure. This will establish whether adaptation to pesticides can accelerate the acquisition or horizontal transfer of resistance elements from exogenous sources. The expected outcomes will be the validation and implementation of an in-vivo plant microbe colonisation model to assess the contributions of pesticide use in promoting microorganism and ARO transfer.