Antimicrobial peptides from the microbiome as modulators of bacterial virulence

来自微生物组的抗菌肽作为细菌毒力的调节剂

• 批准号: RGPIN-2017-05322
• 负责人: Duperthuy, Marylise
• 金额: $ 3.79万
• 依托单位: Université de Montréal
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=760938
• 关键词: Antimicrobial; peptides; microbiome; modulators; bacterial

The gut microbiome has been intensively studied lately because of its fundamental role in human health. However, the molecular dialogue between the bacteria from the microbiome is still poorly understood. My research focus on understanding this dialogue in a cooperative or a competitive bacterial relationship. The bacteria from the microbiome are producing antimicrobial peptides (AMPs), which have an important role in regulating the microbial community. The aim of this proposal is to determine if AMPs produced by the microbiome can modulate the expression and secretion of proteins involved in virulence and resistance in V. cholerae. Therefore, our specific objectives are to: i) Identify and select bacteria from the microbiome that produce AMP(s) active against V. cholerae. Two approaches will be considered. A random approach consisting of the screening of a bacterial collection from the microbiome for their anti-Vibrio activity, followed by an identification of the producer and a purification of the AMPs. The second approach consist on the selection of the AMPs produced by bacteria from the microbiome based on the available literature, eventually followed by a cloning and purification.ii) Determine how the AMPs from the microbiome affect the expression and secretion of proteins from V. cholerae. A global proteomic approach will be performed to identify the protein differentially expressed in presence of AMPs. A construction of the mutants of the genes coding for the identified effectors will follow for the identification of the role of the effector proteins in antimicrobial peptide resistance and in virulence using animal models.iii) Identify the risk of developing a resistance to the AMPs from the microbiome, by cultivating different intestinal pathogens with low concentration of the AMPs from the microbiome.This work will greatly improve our knowledge of bacteria-bacteria communication in the gut at the molecular level. The novelty resides in considering AMPs as molecules that can subvert the signalling pathways of the neighbouring bacteria, including pathogens, therefore modulating their ability to adapt to their environment.

肠道微生物组由于其在人类健康中的重要作用而受到广泛研究。然而，微生物组中细菌之间的分子对话仍然知之甚少。我的研究重点是理解这种对话在合作或竞争的细菌关系。来自微生物组的细菌正在产生抗菌肽（AMP），其在调节微生物群落中具有重要作用。该提案的目的是确定微生物组产生的AMP是否可以调节参与霍乱弧菌毒力和抗性的蛋白质的表达和分泌。因此，我们的具体目标是：i）从微生物组中鉴定和选择产生对霍乱弧菌有活性的AMP的细菌。将考虑两种办法。一种随机方法，包括从微生物组中筛选细菌收集物的抗弧菌活性，然后鉴定生产者并纯化AMP。第二种方法包括基于现有文献从微生物组中选择由细菌产生的AMP，最终进行克隆和纯化。ii）确定来自微生物组的AMP如何影响来自霍乱弧菌的蛋白质的表达和分泌。将进行全局蛋白质组学方法以鉴定在AMP存在下差异表达的蛋白质。随后构建编码所鉴定的效应物的基因的突变体，以使用动物模型鉴定效应物蛋白在抗微生物肽抗性和毒力中的作用。iii）鉴定从微生物组发展对AMP的抗性的风险，通过培养不同的肠道病原体与低浓度的AMP从微生物组。这项工作将大大提高我们的知识，在分子水平上促进肠道中细菌间的交流。新奇之处在于将AMP视为可以破坏包括病原体在内的邻近细菌的信号传导途径的分子，从而调节它们适应环境的能力。