Contribution of altered lipid metabolism to resistance to cell envelope-targeting antimicrobials in MRSA

脂质代谢改变对 MRSA 细胞包膜靶向抗菌药物耐药性的贡献

基本信息

批准号：
10216950
负责人：
Brian James Werth
金额：
$ 46.38万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-08-15 至 2023-06-08
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10216950
关键词：
Address Alleles American Antibiotic Resistance Antibiotics Antimicrobial Resistance Bacteremia Bacteria Biophysics Categories Cell Wall Cell membrane Cessation of life Characteristics Clinical Clinical Management Coupled Daptomycin Development Diagnostic Drug resistance Failure Foundations Gene Expression Gene Mutation Genes Genetic study Genomics Genotype Glycopeptides Goals Health Human In Vitro Individual Infection Lead Libraries Lipids Mass Spectrum Analysis Measures Methicillin Resistance Methodology Modeling Mutation Outcome Parents Pathway interactions Patient-Focused Outcomes Patients Pharmaceutical Preparations Pharmacodynamics Phenotype Phosphatidylglycerols Play Population Analysis Predisposition Prevention Property Resistance Resistance development Role Staphylococcus aureus infection Superbug Techniques Testing Therapeutic Time Transcript Treatment Failure Vancomycin Work antimicrobial base beta-Lactams biological adaptation to stress cell envelope clinically relevant dalbavancin differential expression drug response prediction druggable target genome sequencing improved innovation insight lipid metabolism lipidomics lipoteichoic acid methicillin resistant Staphylococcus aureus mutant novel novel diagnostics novel therapeutics pathogenic bacteria pharmacokinetics and pharmacodynamics predicting response resistance mechanism resistant strain response small molecule specific biomarkers standard of care success synergism transcriptome sequencing transcriptomics whole genome

项目摘要

Project Summary Invasive infections due to the “superbug” methicillin-resistant Staphylococcus aureus (MRSA) are responsible for more deaths than any other drug-resistant bacterial pathogen in the USA. The glycopeptide (GP), vanco- mycin, is the standard of care for the treatment of MRSA, but therapeutic failures are common. Vancomycin is closely related to two other classes of antibiotics that are also important for the treatment of MRSA infections, the lipopeptides (LP) and the lipoglycopeptides (LGP). Drugs from each of these classes can select for cross- resistance to the others to various degrees, but the mechanisms behind this cross-resistance are not well un- derstood. In addition, there is a critical need to develop new diagnostics that can predict drug response to GP, LP, and LGP antimicrobials, and to develop novel therapies that can modulate resistance. Recently, using an innovative lipidomic approach we have observed significant and characteristic changes in lipid metabolism as- sociated with resistance to each class of drugs (GP, LP, and LGP). We hypothesize that lipidomic signatures in the cell membrane reflect specific antibiotic resistance mechanisms and that these lipidomic signatures can be modified by other small molecules to favor a susceptible phenotype. We propose to comprehensively inter- rogate the mechanisms of resistance and cross-resistance to GP, LP, and LGP antimicrobials in MRSA by in- tegrated lipidomics, genomics, and transcriptomics. In AIM 1, our strategy will focus on elucidating the role of altered lipid metabolism in the development of resistant phenotypes in in vitro-selected strains that are re- sistant to GP, LP, and/or LGP using comprehensive lipidomics, coupled with genomics, transcriptomics, stand- ard and advanced susceptibility testing, and quantitative biophysical assessment of cell wall and cell mem- brane properties. Contribution of each gene mutation to the resistant phenotypes will be elucidated by similar characterization of single-gene mutants generated by allelic replacement. In AIM 2, we will test the hypothesis that β-lactams modulate the susceptibility of MRSA to GP, LP, and LGP, at least in part, by modifying the lipid composition of the bacteria. We will examine the synergistic interactions between the study drugs and β- lactams by the integrated omics approach, which would yield insights into the mechanisms of β-lactam synergy with these agents and the β-lactam “seesaw effect”. In AIM 3, we will evaluate the sensitivity of our lipidomic technique to identify sub-MIC differences in susceptibility and predict response to clinically relevant GP, LP, and LGP exposures. We anticipate that this strategy will yield valuable insight into the role of altered lipid me- tabolism in producing antimicrobial resistance. This work is significant because the pathways identified as crit- ical to resistance and susceptible to modulation will lay the foundation for further studies that could lead to re- sistance prevention therapeutics and advanced diagnostics, which in turn will improve human health. The in- novation of this proposal includes the novel lipidomics methodology, the integrated omics approach, and cor- relation of lipidomic signatures with clinically relevant pharmacodynamics endpoints.

项目概要由“超级细菌”耐甲氧西林金黄色葡萄球菌 (MRSA) 引起的侵袭性感染是罪魁祸首在美国，糖肽 (GP)、vanco- 导致的死亡人数比任何其他耐药细菌病原体都要多。霉素是治疗 MRSA 的标准疗法，但万古霉素治疗失败的情况很常见。与其他两类抗生素密切相关，这两种抗生素对于治疗 MRSA 感染也很重要，脂肽（LP）和脂糖肽（LGP）可以从每一类药物中进行交叉选择。不同程度地对其他药物产生抵抗，但这种交叉抵抗背后的机制尚不清楚。此外，迫切需要开发新的诊断方法来预测对 GP 的药物反应， LP 和 LGP 抗菌剂，并最近使用一种可以调节耐药性的新疗法。创新的脂质组学方法我们观察到脂质代谢的显着和特征性变化：与各类药物（GP、LP 和 LGP）的耐药性相关。细胞膜中反映了特定的抗生素耐药机制，这些脂质组学特征可以我们建议通过其他小分子进行修饰以支持易感表型。通过 in- 探究 MRSA 对 GP、LP 和 LGP 抗菌剂的耐药性和交叉耐药性机制在 AIM 1 中，我们的策略将侧重于阐明脂质组学、基因组学和转录组学的作用。在体外选择的菌株中，脂质代谢发生了抗药性表型的改变，这些菌株被重新使用综合脂质组学，结合基因组学、转录组学、标准组学，对 GP、LP 和/或 LGP 有帮助 ard 和先进的药敏试验，以及细胞壁和细胞记忆的定量生物物理评估每个基因突变对抗性表型的贡献将通过类似的方法来阐明。通过等位基因替换产生的单基因突变体的表征在 AIM 2 中，我们将检验假设。 β-内酰胺至少部分通过修饰脂质来调节 MRSA 对 GP、LP 和 LGP 的敏感性我们将检查研究药物和 β- 之间的协同相互作用。通过综合组学方法研究内酰胺，这将深入了解 β-内酰胺协同作用的机制使用这些药物和 β-内酰胺“跷跷板效应”，在 AIM 3 中，我们将评估我们的脂质组学的敏感性。识别亚 MIC 敏感性差异并预测对临床相关 GP、LP、我们预计这一策略将对改变脂质代谢的作用产生有价值的见解。这项工作具有重要意义，因为被确定为关键途径。抗性和易受调制将为进一步的研究奠定基础，这可能会导致重新耐药预防疗法和先进的诊断学，反过来将改善人类健康。该提案的创新包括新的脂质组学方法、综合组学方法以及相关的脂质组学特征与临床相关药效学终点的关系。