Cell envelope stress responses and the mechanism of antibiotic tolerance in Gram-negative pathogens

革兰氏阴性病原体的细胞包膜应激反应和抗生素耐受机制

基本信息

批准号：
10078589
负责人：
Tobias Doerr
金额：
$ 39.23万
依托单位：
CORNELL UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-10 至 2023-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10078589
关键词：
Acinetobacter baumannii Adjuvant Aftercare Animal Model Anti-Bacterial Agents Antibiotic Resistance Antibiotic Therapy Antibiotics Bacteria Biochemical Biological Models Cell Shape Cell Wall Cell membrane Cells Cholera Clinical Clinical Treatment Complex Data Data Set Development Down-Regulation Drug Targeting Enterobacter cloacae Excision Exhibits Exposure to Genes Genetic Goals Gram-Negative Bacteria Haemophilus influenzae Homeostasis In Vitro Individual Infection Iron Knowledge Lipids Maintenance Measures Mediating Membrane Metabolic Metals Microbe Modeling Modern Medicine Monobactams Normal Cell Pathway interactions Penicillins Pharmaceutical Preparations Phospholipids Population Pseudomonas aeruginosa Recovery Regulon Resistance Resolution Role Shapes Signal Induction Signal Transduction Stress Superoxide Dismutase System Testing Translating Treatment Failure Up-Regulation Vibrio cholerae Withdrawal antibiotic design antibiotic tolerance antimicrobial bactericide beta-Lactams biological adaptation to stress candidate identification cell envelope cell motility clinical practice design experimental study in vivo insight member membrane synthesis novel pathogen protein-histidine kinase rapid growth recurrent infection repaired response transcriptome sequencing

项目摘要

Project Summary Bacteria often resist killing by normally bactericidal antibiotics, resulting in clinical treatment failure and the development of antibiotic resistance. The ability to survive damage elicited by exposure to antibiotics is termed tolerance. Tolerance is likely responsible for the recurrence of infections after discontinuation of antimicrobial therapy, and provides a reservoir of a bacterial population that can develop full scale resistance. An extreme case of tolerance is the formation of persister cells, which do not experience antibiotic-induced damage due to dormancy. However, we and others have found that many Gram-negative pathogens (Vibrio cholerae, Pseudomonas aeruginosa, Enterobacter cloacae, Haemophilus influenzae and Acinetobacter baumannii) are fully susceptible to damage induced by cell wall acting antibiotics (beta lactams), but yet survive at very high levels. Survival is enabled through the formation of viable spheres that are devoid of detectable cell wall material and that recover to normal shape upon withdrawal of the antibiotic. In our model organism, the cholera pathogen V. cholerae, tolerance is promoted by cell envelope stress responses, especially the two-component system WigKR. WigKR is induced by cell wall acting antibiotics and mounts a complex response that ultimately enables recovery from the spherical state. This response includes upregulation of cell wall synthesis functions, outer membrane synthesis, phospholipid synthesis and downregulation of motility and iron acquisition genes. How this response promotes tolerance is poorly understood, and so are the mechanisms of tolerance in other Gram-negative bacteria. Here, we aim to interrogate V. cholerae's cell envelope stress responses and their relationship with beta lactam tolerance and post-antibiotic recovery. Using genetic and biochemical approaches, we will find the elusive induction signal sensed by the histidine kinase WigK. Leveraging extensive datasets comprehensively describing the WigKR regulon, we will measure each individual regulon member's contribution to beta lactam tolerance. Lastly, we will apply what we have learned in the V. cholerae model to other Gram-negative pathogens exhibiting high beta lactam tolerance, specifically E. cloacae and P. aeruginosa. Our experiments will yield novel insight into the mechanisms of antibiotic tolerance and result in the identification of candidate drug targets for anti-tolerance adjuvants of beta lactams.

项目摘要细菌通常会通过正常杀菌性抗生素抗击，导致临床治疗衰竭和抗生素耐药性的发展。暴露于抗生素引起的损害生存的能力称为宽容。耐受性可能导致抗菌药物中断后感染的复发治疗，并提供可营造全尺度耐药性的细菌种群的储层。极端耐受性的情况是持久细胞的形成，不会遭受抗生素引起的损害休眠。但是，我们和其他人发现许多革兰氏阴性病原体（Vibrio Cholerae，铜绿假单胞菌，肠杆菌，流感嗜血杆菌和baumannii）是完全容易受到细胞壁作用抗生素（βlacTAMS）诱导的损害，但在很高的水平。通过形成没有可检测到的细胞壁的可行球的形成来实现生存材料并在戒断抗生素后恢复到正常形状。在我们的模型有机体中，霍乱病原体V.霍乱，耐受性是由细胞包络应力反应促进的，尤其是两个组件系统wigkr。 WIGKR是由细胞壁作用抗生素诱导的，并安装了一个复杂的反应，最终使从球形状态恢复。该响应包括细胞壁合成功能的上调，外膜合成，磷脂合成以及运动性和采集基因的下调。这种反应如何促进宽容的理解很少，而其他宽容的机制也是如此革兰氏阴性细菌。在这里，我们旨在询问V.霍乱的细胞信封压力反应及其与β腹酰胺耐受性和抗生素后恢复的关系。使用遗传和生化方法是，我们将发现组氨酸激酶假发感知的难以捉摸的诱导信号。利用广泛的数据集全面描述了wigkr条件，我们将衡量每个单独的条件成员对β乳糖耐受性的贡献。最后，我们将应用我们在V.霍乱中学到的知识表现出较高βlacTAM耐受性的其他革兰氏阴性病原体的模型，特别是E. cloacae和P. 铜绿。我们的实验将产生对抗生素耐受性机理的新见解，并导致鉴定βlacTAMS抗耐受性佐剂的候选药物靶标。