Polymicrobial interactions between commensal obligate anaerobic bacteria and cystic fibrosis pathogen P. aeruginosa

共生专性厌氧菌与囊性纤维化病原体铜绿假单胞菌之间的多种微生物相互作用

• 批准号: 10275319
• 负责人: Britney Lashawn Hardy
• 金额: --
• 依托单位: NATIONAL CANCER INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10275319
• 关键词: Polymicrobial; interactions; between; commensal; obligate

ABSTRACT It has become apparent that the human microbiota impacts virtually every facet of human health, including directly influencing clinical outcomes for certain diseases. The mechanisms that mediate these effects are often the polymicrobial interactions between incoming pathogens and commensal microbes. In Cystic Fibrosis (CF), a genetic disease in which patients are often afflicted with chronic bacterial infections, most notably Pseudomonas aeruginosa, the effect of the resident anaerobes in disease outcome is conflicting and poorly studied. However, microbiota-based studies have revealed that specific resident obligate anaerobic respiratory bacteria are associated with improved CF outcomes, and limited evidence suggests that specific obligate anaerobic bacteria impair P. aeruginosa colonization. Indeed, I recently discovered that the obligate anaerobic respiratory bacterial species Porphyromonas catoniae inhibits P. aeruginosa growth by a contact-independent mechanism. Genomic mining of the P. catoniae genome revealed no gene clusters known to be associated with antimicrobial synthesis, we therefore hypothesize that P. catoniae inhibits P. aeruginosa by a novel mechanism. The proposal will take a multifarious approach to investigate P. catoniae inhibition of P. aeruginosa. To this end, a P. catoniae transposon mutant strain library will be constructed and screened to identify the gene(s) responsible for inhibitory activity. Mass spectrometry will be utilized to characterize the P. catoniae “secretome” to identify potential anti-P. aeruginosa compound(s). The P. aeruginosa global transcriptional response to P. catoniae will be examined and measured by RNA-seq. Moreover, P. aeruginosa Tn-seq will be used to illuminate which genes are associated with survival in the presence of P. catoniae. Furthermore, we will assess the effects of bacterial lifestyle (planktonic vs. biofilm), CF relevant environmental stimuli, and the addition of other obligate anaerobic respiratory bacteria on this interaction. Alternations in biofilm biogeography under CF relevant conditions including the presence of other commensals will be assessed with fluorescence confocal microscopy. En masse, this proposal seeks to provide novel insight into interbacterial behavior and lifestyle that ultimately could reveal novel antimicrobials and/or molecular target(s) to treat chronic P. aeruginosa infections and improve the clinical outcomes for CF patients.

摘要 很明显，人类微生物群几乎影响人类健康的各个方面，包括 直接影响某些疾病的临床结果。调节这些效应的机制是 通常是外来病原体和肠道微生物之间的多微生物相互作用。肺囊性纤维化患者 (CF)这是一种遗传性疾病，患者通常患有慢性细菌感染， 铜绿假单胞菌，常驻厌氧菌在疾病结局中的作用是相互矛盾的， 研究了然而，基于微生物的研究表明，特定的居民专性厌氧呼吸 细菌与CF结果的改善相关，有限的证据表明，特定的专性 厌氧菌损害铜绿假单胞菌的定植。事实上，我最近发现，专性厌氧 呼吸道细菌物种卡他卟啉单胞菌通过非接触性 机制对卡特彼勒基因组的基因组挖掘显示， 因此，我们假设，P. catastrophin通过一种新的抗菌素合成抑制铜绿假单胞菌。 机制建议采取多种方法研究P. catenarum对P. catenarum的抑制作用。 铜绿。为此，将构建并筛选P. category转座子突变菌株文库， 鉴定负责抑制活性的基因。将采用质谱法表征P。 催化剂“分泌组”以鉴定潜在的抗铜绿假单胞菌化合物。绿脓杆菌全球 将通过RNA-seq检查和测量对猫疫丙酸杆菌的转录应答。此外，铜绿假单胞菌 Tn-seq将用于阐明哪些基因与在存在猫肺炎支原体的情况下的存活相关。 此外，我们还将评估细菌生活方式（浮游生物与生物膜）、CF相关环境 刺激，以及添加其他专性厌氧呼吸细菌对这种相互作用的影响。变更 将在CF相关条件下（包括存在其他微生物）进行生物膜层析， 用荧光共聚焦显微镜评估。因此，这项建议旨在提供新的见解， 细菌间行为和生活方式，最终可以揭示新的抗菌剂和/或分子靶点 治疗慢性铜绿假单胞菌感染并改善CF患者的临床结局。