Oxidative Stress Resistance Mechanisms in Filifactor Alocis

Filifactor Alocis 的氧化应激抵抗机制

• 批准号: 10217430
• 负责人: Arunima Mishra
• 金额: $ 15.8万
• 依托单位: LOMA LINDA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10217430
• 关键词: ATP Hydrolysis; ATP-Binding Cassette Transporters; Adult; Alleles; Anaerobic Bacteria; Bacteria; Basic Science; Biological Models; Cell physiology; Cells; Coculture Techniques; Communities; Complex; Data; Development; Diagnostic; Disease; Endodontics; Environment; Etiology; Exposure to; Forsythia; Fusobacterium; Gene Expression Profile; Genes; Genetic; Genome; Goals; Growth; Health; Homeostasis; Human; Hydrogen Peroxide; Infection; Inflammatory; Light; Manganese; Molecular; Molecular Genetics; Mutagenesis; Oral; Organism; Oxidative Stress; Pathogenesis; Pathogenicity; Patients; Periodontal Diseases; Periodontal Pocket; Periodontitis; Phylogenetic Analysis; Play; Porphyromonas gingivalis; Prevention; Prophylactic treatment; Reactive Oxygen Species; Refractory; Reporting; Research; Resistance; Ribosomal RNA; Rod; Role; Severity of illness; Stress; Structure of gingival sulcus; System; Treponema; Treponema denticola; Virulence; Virulence Factors; bacterial community; base; diagnostic biomarker; emerging pathogen; genetic manipulation; innovation; microbial community; microbiome research; new therapeutic target; novel therapeutic intervention; novel therapeutics; oral microbiome; pathogen; periodontopathogen; resistance mechanism; response; tool; transcriptome sequencing; virtual

A. PROJECT SUMMARY/ABSTRACT Recent oral microbiome studies have recognized a myriad of as-yet-culturable and fastidious organisms that have shown a strong correlation with periodontal disease severity. It is likely that the emerging new pathogens may play a more significant role in the disease compared to the traditional “red complex” bacteria Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola. One such previously unrecognized organism, Filifactor alocis, is a Gram-positive, asaccharolytic, obligate anaerobic rod. Several recent studies have found this bacterium at significantly higher levels in adult or refractory periodontitis patients and have suggested that it could be included as a diagnostic indicator of periodontal disease. Currently, there is little or no information on survival mechanisms and virulence of F. alocis. Primarily, this is due to the unavailability of an efficient genetic system to allow genetic manipulations of the F. alocis genome. In response to environmental stress, our preliminary studies showed that F. alocis is relatively more resistant to H2O2-induced oxidative stress compared to P. gingivalis. Also, under H2O2-induced stress conditions, the survival of P. gingivalis is enhanced more than 4-fold in the presence of F. alocis. These observations suggest that F. alocis may have the ability to modify/reduce the oxidative stress environment and stabilize the microbial community of the periodontal pocket. In an RNA-seq analysis, the transcriptional profile of F. alocis showed that in coculture with P. gingivalis (compared to F. alocis monoculture) under H2O2-induced stress, the most highly upregulated genes in F. alocis encode for a putative manganese ABC transporter FA0894-FA0895-FA0896-FA0897. Manganese has been proposed to detoxify reactive oxygen species and protect bacteria from oxidative stress. It is our hypothesis that the F. alocis hypothetical ATP transporter, FA0894-FA0897, may play an important role in enhanced protection/survival of P. gingivalis against H2O2-induced stress. We wish to understand the modulation of F. alocis potential virulence factors in response to interaction with P. gingivalis and evaluate if they contribute to protection/persistence of P. gingivalis against the oxidative environment of the periodontal community. The proposed specific aims are: (1) to evaluate the specific role(s) of F. alocis putative ABC transporter FA0894-FA0897 in the protection/survival of P. gingivalis under H2O2-induced stress. (2) to develop an efficient genetic system for Filifactor that includes a markerless, in-frame deletion system and/or transposon mutagenesis system. Collectively, the data generated will facilitate a comprehensive assessment of the molecular mechanism(s) and overall interplay involving F. alocis and the ‘keystone’ pathogen P. gingivalis. It will also generate a polymicrobial model system that may facilitate the development of novel therapeutic interventions to aid in the control and prevention of periodontal disease. Furthermore, the new genetic manipulation system will help to uncover the relative significance of F. alocis in the etiology of periodontal disease.

A.项目总结/摘要 最近的口腔微生物组研究已经认识到， 牙周病的严重程度与牙周病的严重程度密切相关。很可能，新兴的 与传统的“红色复合物”相比，新的病原体可能在疾病中发挥更重要的作用。 细菌牙龈卟啉单胞菌、Tannerella gingivalis和齿垢密螺旋体。一个这样的先前 未识别的微生物，Filifactoralocis，是一种革兰氏阳性、溶砷、专性厌氧杆菌。几 最近的研究发现，这种细菌在成年人或难治性牙周炎患者中的水平明显较高 并建议将其作为牙周病的诊断指标。 目前，关于F. alocis。 首先，这是由于没有一个有效的遗传系统，使遗传操作的F。 阿洛西斯基因组。初步研究表明，F. Alocis相对来说 与牙龈卟啉单胞菌相比，其对H2 O2诱导的氧化应激的抗性更强。此外，在H2 O2诱导的胁迫下， 条件下，牙龈卟啉单胞菌的存活率在F. alocis。这些 观察表明，F. Alocis可能具有改变/减少氧化应激环境的能力， 稳定牙周袋的微生物群落。在RNA-seq分析中， 荷兰盾alocis与牙龈卟啉单胞菌共培养时，Alocis monoculture）在H2 O2诱导下 胁迫下，F. alocis编码一种假定锰ABC转运蛋白 FA0894-FA0895-FA0896-FA0897。锰已被提出用于解毒活性氧物质， 保护细菌免受氧化应激。我们假设F. alocis假设的ATP转运蛋白， FA 0894-FA 0897，可能在增强牙龈卟啉单胞菌的保护/存活中起重要作用， H2 O2诱导的应激。我们希望了解F的调制。alocis潜在毒力因子 反应与牙龈卟啉单胞菌的相互作用，并评估它们是否有助于保护/持久的P。 牙龈对牙周社区的氧化环境。建议的具体目标是：（1） 评价F. alocis推定的ABC转运蛋白FA 0894-FA 0897在保护/存活中的作用 牙龈卟啉单胞菌在H2 O2诱导的应激下的生长。(2)为Filifactor开发一个有效的遗传系统，包括 无标记的框内缺失系统和/或转座子诱变系统。 总的来说，所产生的数据将有助于对分子生物学的全面评估。 机制和涉及F的整体相互作用。alocis和'基石'病原体牙龈卟啉单胞菌。它还将 产生一个多微生物模型系统，可以促进新的治疗干预措施的发展 以帮助控制和预防牙周病。此外，新的基因操作系统 将有助于揭示F的相对意义。牙周病的病因学研究进展