The roles of the Pseudomonas aeruginosa Prc/AlgO protease - Resubmission - 1

铜绿假单胞菌 Prc/AlgO 蛋白酶的作用 - 重新提交 - 1

基本信息

批准号：
10312116
负责人：
ANDREW J. DARWIN
金额：
$ 21.19万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-12-07 至 2023-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10312116
关键词：
Acute Pneumonia Address Adopted Affect Alginates Anabolism Antibiotic Resistance Antibiotics Bacteria C-terminal Catalytic Domain Cell Wall Cells Cystic Fibrosis Dangerousness Data Development Disease Disease Outbreaks Drug Targeting Enzymes Escherichia coli Funding Future Goals Health Host Defense Human Hydrolase Immune system Individual Infection Life Link Metabolism Modeling Multi-Drug Resistance N-Acetylmuramoyl-L-alanine Amidase N-terminal Names Nosocomial Infections Patients Peptide Hydrolases Peptidoglycan Phenotype Play Polysaccharides Process Production Prognosis Proteins Pseudomonas aeruginosa Regulation Regulon Research Role Sigma Factor Testing Therapeutic Intervention Virulence Work Wound Infection acute infection cell envelope cell growth chronic infection cleavage factor cost crosslink cystic fibrosis patients extracellular genetic regulatory protein human pathogen insight lung colonization mucoid new therapeutic target novel novel therapeutic intervention pathogen pathogenic bacteria periplasm resistant strain targeted treatment therapeutic target

项目摘要

PROJECT SUMMARY The bacterial pathogen Pseudomonas aeruginosa causes life-threatening human illnesses, including acute pneumonia, long-term lung colonization in cystic fibrosis patients, and severe wound infections. Most infections are associated with compromised host defenses and this, together with the common environmental occurrence of P. aeruginosa, makes it a leading cause of hospital-acquired infections. Treatment of P. aeruginosa disease is often challenging, in part because of its intrinsic resistance to antibiotics as well as occasional outbreaks of multi-drug-resistant strains. Therefore, there is an urgent need to characterize new targets for therapeutic attack. The P. aeruginosa cell envelope contains a C-terminal processing protease (CTP) named CtpA, which is essential for acute infection. CtpA has adopted a similar role to that of the only CTP found in Escherichia coli, Prc, even though CtpA and Prc are quite different from each other. Both CtpA in P. aeruginosa, and Prc in E. coli, degrade enzymes that remodel the bacterial cell wall. This is intriguing because whereas many bacteria like E. coli have only one CTP, P. aeruginosa has two, and the second one is named Prc because it is very similar to E. coli Prc. This raises the new question for this exploratory/developmental proposal: if CtpA achieves the role played by Prc in E. coli, then what does Prc do in Pa? Prc has been proposed to cleave the negative regulatory protein MucA, triggering extracellular polysaccharide production and a phenotype associated with a poor prognosis in cystic fibrosis patients. However, neither MucA or any other P. aeruginosa protein has been demonstrated to be a Prc substrate. From our preliminary data, we are proposing an exciting new model for the differential control of at least one PG cross-link hydrolase by both Prc and CtpA. Together with our other observations suggesting that Prc affects the cell wall, this supports our central hypothesis, which is that Prc cleaves important proteins involved in cell wall metabolism, and that this might have an indirect impact on the cleavage of the anti-sigma factor MucA. To test this hypothesis, we will: (1) Determine if Prc and CtpA play different roles in degrading common substrates and (2) Establish how Prc affects alginate regulation and the mucoid conversion phenotype. This work will impact our understanding of fundamental, conserved processes important to almost all bacteria. It will also provide the first clear insight into exactly what Prc does in Pa, and the mechanism(s) by which it affects alginate biosynthesis, mucoid conversion, and cell wall features that impact human health. Understanding these mechanisms might ultimately help the development of new therapeutic strategies against this widespread, dangerous and very costly human pathogen.

项目概要细菌病原体铜绿假单胞菌会导致危及生命的人类疾病，包括急性肺炎、囊性纤维化患者肺部长期定植以及严重伤口感染。大多数感染与宿主防御受损有关，这与常见的环境事件有关铜绿假单胞菌，使其成为医院获得性感染的主要原因。铜绿假单胞菌病的治疗通常具有挑战性，部分原因是其对抗生素的固有耐药性以及偶尔爆发的多重耐药菌株。因此，迫切需要确定新的治疗靶点攻击。铜绿假单胞菌细胞膜含有一种名为 CtpA 的 C 末端加工蛋白酶 (CTP)，它对于急性感染至关重要。 CtpA 具有与埃希氏菌中唯一发现的 CTP 类似的作用大肠杆菌、Prc，尽管 CtpA 和 Prc 彼此有很大不同。铜绿假单胞菌中的 CtpA 和大肠杆菌，降解重塑细菌细胞壁的酶。这很有趣，因为尽管许多细菌就像大肠杆菌只有一个CTP，铜绿假单胞菌有两个，第二个被命名为Prc，因为它非常类似于 E. coli Prc。这为这个探索性/发展性提案提出了一个新问题：如果 CtpA 实现了Prc在大肠杆菌中所扮演的角色，那么Prc在Pa中又做了什么呢？已建议中华人民共和国分裂负调节蛋白 MucA，触发细胞外多糖产生和表型与囊性纤维化患者的不良预后相关。然而，MucA 或任何其他铜绿假单胞菌蛋白质已被证明是 Prc 底物。根据我们的初步数据，我们提出了一个令人兴奋的方案 Prc 和 CtpA 对至少一种 PG 交联水解酶进行差异控制的新模型。一起我们的其他观察表明 Prc 影响细胞壁，这支持了我们的中心假设，即 Prc 裂解参与细胞壁代谢的重要蛋白质，这可能具有间接作用对抗 Sigma 因子 MucA 裂解的影响。为了检验这个假设，我们将： (1) 确定 Prc 和 CtpA 在降解常见底物中发挥不同的作用，并且 (2) 确定 Prc 如何影响藻酸盐调节和粘液转化表型。这项工作将影响我们对基本的、保守的对几乎所有细菌都很重要的过程。它还将首次清晰地了解中国在做什么 Pa 及其影响藻酸盐生物合成、粘液转化和细胞壁特征的机制从而影响人类健康。了解这些机制可能最终有助于开发新的针对这种广泛、危险且昂贵的人类病原体的治疗策略。