Contribution of extracellular enzymes to Staphylococcus aureus biofilm development

胞外酶对金黄色葡萄球菌生物膜发育的贡献

• 批准号: 10461797
• 负责人: Tammy L Kielian
• 金额: $ 45.33万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10461797
• 关键词: Address; Adenosine; Anti-Inflammatory Agents; Antibiotics; Behavior; Biological Markers; Carbon; Catabolism; Cell physiology; Collaborations; DNA; Defect; Development; Devices; Digestion; Disaccharides; Disease; Environment; Enzymes; Excision; Foreign Bodies; Gene Expression; Genus staphylococcus; Glycosaminoglycans; Growth; Healthcare Systems; Human; Hyaluronan; Hyaluronidase; Immune; In Vitro; Infection; Inflammation; Inflammatory; Innovative Therapy; Joint Prosthesis; Knock-out; Label; Metabolic; Metabolism; Microbial Biofilms; Mutation; Nature; Nutrient; Nutritional; Nutritional status; Pathway interactions; Patient-Focused Outcomes; Patients; Phenotype; Polymers; Production; Property; Regulation; Reporting; Resistance; Role; Scheme; Site; Source; Staphylococcus aureus; Staphylococcus aureus infection; Synovial Fluid; System; Testing; bioimaging; cell community; chemotherapy; defined contribution; exoenzyme; extracellular; follow-up; genetic analysis; health care settings; inhibitor; joint infection; metabolomics; mutant; nuclease; pathogenic bacteria; sensor; transcriptome sequencing; transcriptomics

PROJECT SUMMARY Staphylococcus aureus is one of the most problematic bacterial pathogens in our healthcare settings. S. aureus can survive and persist in the host by developing into an encased community of cells called a biofilm, and numerous studies have demonstrated that biofilms are resistant to host immune defenses and chemotherapies. Our central PPG hypothesis is that S. aureus biofilm development creates unique metabolic niches that promote an immune suppressive environment. In this proposal (Project 3), we are focusing on the contribution of S. aureus extracellular enzymes to biofilm growth and maturation, persistence in the host, and ultimately dissemination to a new site. Of the many enzymes that S. aureus secretes, we will prioritize hyaluronidase (HysA) and nuclease (Nuc1), as they have commonalities in biofilm-host interaction phenotypes and regulatory schemes. We recently demonstrated that hyaluronan accumulates in an S. aureus biofilm infection and that HysA can degrade this host glycosaminoglycan to disaccharides (HA-DS). Our preliminary studies indicate that HA-DS can serve as a carbon source through an unknown catabolic pathway, and this disaccharide has additional anti-inflammatory properties that could be contributing to the persistent nature of S. aureus biofilm infections. In Specific Aim 1, we will determine the role and regulation of hyaluronan metabolism in S. aureus biofilm maturation. We will characterize the HA-DS catabolic pathway using genetic analysis and labeling studies in collaboration with the Metabolomics Core. We will also test catabolic pathway knockouts in biofilm maturation and foreign-body infections, and investigate the contribution of CodY and CcpA to regulation of hyaluronan catabolism. Additionally, S. aureus will be grown on HA-DS and RNAseq performed to identify global transcriptomic changes. In Specific Aim 2, we will investigate how S. aureus enzymatic degradation of host polymers impacts the biofilm anti-inflammatory state. In collaboration with Dr. Tammy Kielian (PPG Project 4), we will assess the effect of HA-DS, as well as Nuc1 and HysA enzymes and their regulators, on immune cell function. We will also determine the impact of HA-DS and HysA inhibitors on biofilm infection, and test whether HA-DS is a biomarker for S. aureus in human synovial fluid from patients with prosthetic joint infection (PJI). In Specific Aim 3, we will examine S. aureus exo-enzyme regulation and function in biofilm dispersal. We hypothesize that CodY controls dissemination from S. aureus biofilms in an enzyme and nutrient dependent manner. We will investigate the contribution of Nuc1 and HysA, along with CodY and SaeRS regulators, to biofilm dispersal in vitro and during foreign body infection. We will also examine the impact of nutritional status on CodY activity during biofilm formation and dispersal in collaboration with Dr. Ken Bayles (PPG Project 1) and the Bioimaging Core. Finally, we will determine the role of aureusimine molecules in S. aureus biofilm development. Collectively these studies will define the contribution of S. aureus exo-enzymes to biofilm metabolism, development and persistence, potentially leading to innovative therapies for biofilm infections.

项目摘要 金黄色葡萄球菌是我们医疗保健环境中最有问题的细菌病原体之一。 S.金黄色葡萄酒 可以通过发展为一个称为生物膜的细胞社区，可以在宿主中生存并持续存在 许多研究表明，生物膜对宿主防御和化学疗法具有抗性。 我们的中心PPG假设是，金黄色葡萄球菌生物膜的发展产生了独特的代谢壁ches来促进 免疫抑制环境。在此提案（项目3）中，我们关注S的贡献。 金黄色金黄色细胞外酶以生物膜生长和成熟，宿主的持久性，最终 传播到新网站。在金黄色葡萄球菌分泌的许多酶中，我们将优先考虑透明质酸酶（HYSA） 和核酸酶（NUC1），因为它们在生物膜宿主相互作用表型和调节中具有共同点 方案。我们最近证明了透明质酸在金黄色葡萄球菌生物膜感染中积聚，并且 HYSA可以将此宿主糖胺聚糖降解为二糖（HA-DS）。我们的初步研究表明 HA-DS可以通过未知的分解代谢途径作为碳源，并且这种二糖具有 可能导致金黄色葡萄球菌生物膜持续性的其他抗炎特性 感染。在特定目标1中，我们将确定透明质酸代谢在金黄色葡萄球菌中的作用和调节 生物膜成熟。我们将使用遗传分析和标记研究来表征HA-DS分解代谢途径 与代谢组学核心合作。我们还将测试生物膜成熟的分解代谢途径敲除 和外国体内感染，并研究了Cody和CCPA对透明质酸调节的贡献 分解代谢。此外，金黄色葡萄球菌将在HA-DS和RNASEQ上生长以识别全局 转录组变化。在特定目标2中，我们将研究宿主的金黄色葡萄球菌酶促降解 聚合物会影响生物膜抗炎状态。与Tammy Kielian博士（PPG项目4）合作， 我们将评估HA-DS以及NUC1和HYSA酶及其调节剂对免疫细胞的影响 功能。我们还将确定HA-DS和HYSA抑制剂对生物膜感染的影响，并测试是否是否 HA-DS是人义关节感染患者（PJI）的人类滑液中金黄色葡萄球菌的生物标志物。在 具体目的3，我们将检查Aureus Exo-enzyme S. exo-enzyme调节和生物膜分散的功能。我们 假设Cody控制酶和养分依赖性的金黄色葡萄球菌生物膜的传播 方式。我们将研究Nuc1和Hysa以及Cody和Saers调节剂对生物膜的贡献 在体外和外国体内感染期间分散。我们还将检查营养状况对Cody的影响 与Ken Bayles博士（PPG Project 1）合作的生物膜形成和分散期间的活动 生物成像核心。最后，我们将确定金黄色分子在金黄色葡萄球菌生物膜发育中的作用。 这些研究集体定义了金黄色葡萄球菌外酶对生物膜代谢的贡献， 发展和持久性，有可能导致生物膜感染的创新疗法。