Staphylococcus aureus and Pseudomonas aeruginosa interactions in wound pathogenesis

金黄色葡萄球菌和铜绿假单胞菌在伤口发病机制中的相互作用

• 批准号: 10531680
• 负责人: ALEXANDER R HORSWILL
• 金额: $ 18.73万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-01 至 2024-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10531680
• 关键词: Accounting; Address; Affect; Anabolism; Antibiotic Resistance; Antibiotic Therapy; Antibiotics; Binding; Biochemical Genetics; Biological; Chemicals; Chronic; Collaborations; Communities; Data; Development; Disease; Disease Outcome; Elements; Enterococcus; Environment; Enzymes; Exposure to; Gene Expression; Gene Proteins; Generations; Genes; Genus staphylococcus; Goals; Growth; Immune system; In Vitro; Infection; Iron; Knowledge; Lead; Leg Ulcer; Libraries; Metabolic Biotransformation; Metabolism; Metabolite Interaction; Methods; Methylation; Methyltransferase; Microbial Biofilms; Modeling; Modification; Morbidity - disease rate; Mus; Outcome; Pathogenesis; Pathway interactions; Patients; Persons; Physiology; Prevalence; Production; Property; Pseudomonas; Pseudomonas aeruginosa; Pyocyanine; Quinolones; Recurrence; Regulation; Siderophores; Signal Pathway; Site; Skin Tissue; Soft Tissue Infections; Staphylococcus aureus; Surveillance Program; System; Testing; United States; Virulence Factors; Work; Wound Infection; Wound models; alternative treatment; antibiotic tolerance; antimicrobial; cell behavior; chronic infection; chronic wound; co-infection; genetic analysis; immune clearance; improved; mass spectrometric imaging; methicillin resistant Staphylococcus aureus; microbial community; mutant; novel; pathogen; pathogenic bacteria; polymicrobial disease; pyochelin; quorum sensing; receptor; recurrent infection; screening; uptake; wound; wound environment

PROJECT ABSTRACT Patients with chronic wound infections have a rich microbial community and several bacterial species have been identified as the main drivers of persistent disease. Two of the most prominent wound pathogens are Staphylococcus aureus (including methicillin-resistant S. aureus (MRSA)), and Pseudomonas aeruginosa. The SENTRY antimicrobial surveillance program identified S. three 11%, aureus P. aeruginosa and Enterococcus spp. as the main pathogens causing skin and soft tissue infections (SSTI) in the United States accounting for 44%, and 9% of all SSTI during the years 1998 and 2004. , , Chronic leg ulcers (CLUs) affect 1-2% of people worldwide, are a major cause of prolonged morbidity and have a high recurrence rate. S. aureus and P. aeruginosa are the most common agents isolated from CLUs usually as biofilm resistant to antibiotic therapy. Biofilms are notoriously difficult to eradicate, due to their recalcitrance to antibiotics and ability to evade clearance by the immune system. There is evidence that these two pathogens can exchange specialized metabolites that have the potential to alter cellular behavior and lead to community-wide antibiotic tolerance. Specifically, in vitro co-cultivation studies with S. aureus increased Pseudomonas quinolone gene expression that regulates the expression of several quorum-sensing dependent P. aeruginosa virulence factors and iron acquisition systems. As the prevalence of MRSA increases in the US, new strategies are necessary to treat chronic and recurrent infections. Therefore, the long-term goal is to develop alternative treatment options for chronic wound patients infected by S. aureus and P. aeruginosa. The objective of this proposal is to determine the biological consequences of MRSA modification of P. aeruginosa pyochelin. The rationale underlying this proposal is our preliminary findings that S. aureus and P. aeruginosa act synergistically, which may in part explain why co- infections with these two pathogens lead to worse outcomes. In preliminary imaging mass spectrometry studies, we determined that a novel methylated pyochelin derivative is produced during the interaction of MRSA and P. aeruginosa. We identified the MRSA gene responsible and we can detect this new metabolite in a mouse wound infection model. Our initial studies confirm that the pyochelin originates from P. aeruginosa and then is enzymatically converted by MRSA into a new methylated form. We hypothesize that MRSA methylates pyochelin to compete in a polymicrobial environment. In order to test this hypothesis we will (i) characterize methylated pyochelin generated by MRSA through biochemical, genetic and infection modeling methods and; (ii) determine the functional consequences of methylated pyochelin on P. aeruginosa physiology and pathogenesis. The expected outcomes of this work will increase our understanding the biosynthesis and biological activities of specialized metabolites that drive inter-species interactions to better predict infection outcomes and to develop new treatment approaches.

项目摘要 患有慢性伤口感染的患者具有丰富的微生物群落，几种细菌种类已经 被确定为持续性疾病的主要驱动因素。两种最突出的伤口病原体是 金黄色葡萄球菌（包括甲氧西林的金黄色葡萄球菌（MRSA））和铜绿假单胞菌。这 哨兵抗菌监测计划确定了S。 三 11％， 金黄色葡萄球菌和肠球菌属。作为 在美国引起皮肤和软组织感染（SSTI）的主要病原体占44％， 在1998年和2004年中，所有SSTI的9％。 ，，， 慢性腿溃疡（CLUS）影响1-2％的人 在全球范围内，是发病率延长的主要原因，并且复发率高。 S.金黄色葡萄球菌和P。 铜绿物是通常从CLU中分离出的最常见药物，通常是对抗生素疗法抗性的生物膜。 由于生物膜对抗生素的顽固和逃避清除能力，因此很难根除生物膜 通过免疫系统。有证据表明，这两种病原体可以交换专门的代谢产物 有可能改变细胞行为并导致社区范围的抗生素耐受性。具体而言，体外 与金黄色葡萄球菌共培养研究增加了奎诺酮基因表达，从而调节 表达几个依赖于铜绿假单胞菌的毒力因子和铁采集系统的表达。 随着美国MRSA的患病率的增加，需要新的策略来治疗慢性和经常性 感染。因此，长期目标是为慢性伤口患者开发替代治疗选择 由金黄色葡萄球菌和铜绿假单胞菌感染。该提议的目的是确定生物学 MRSA修饰铜绿假单胞菌的后果。该提议的基本原理是我们的 初步发现，金黄色葡萄球菌和铜绿假单胞菌是协同作用的，这可能部分解释了为什么共同 这两种病原体的感染导致结果较差。在初步成像质谱研究中， 我们确定在MRSA和P的相互作用期间产生了一种新型的甲基化的毕胆素衍生物。 铜绿。我们确定了负责的MRSA基因，我们可以在小鼠伤口中检测到这种新的代谢产物 感染模型。我们的初步研究证实毕胆素起源于铜绿假单胞菌，然后是 通过MRSA转化为一种新的甲基化形式。我们假设MRSA甲基化 毕叶素在多数型环境中竞争。为了检验此假设，我们将（i）表征 MRSA通过生化，遗传和感染建模方法产生的甲基化的毕胆素和； （ii）确定甲基化楼锡素对铜绿假单胞菌生理学和 发病。这项工作的预期结果将增加我们的理解生物合成和 驱动种间相互作用以更好地预测感染的专门代谢产物的生物学活性 结果并开发新的治疗方法。