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

• 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
• 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

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.

项目摘要 细菌病原体铜绿假单胞菌会引起威胁生命的人类疾病，包括急性 肺炎，囊性纤维化患者的长期肺定植和严重的伤口感染。大多数感染 与受损的宿主防御能力有关，这与常见的环境发生有关 铜绿假单胞菌使其成为医院获得感染的主要原因。铜绿假单胞菌疾病的治疗 通常具有挑战性，部分原因是它对抗生素的内在抗性以及偶尔的爆发 多药抗性菌株。因此，迫切需要表征治疗的新目标 攻击。铜绿假单胞菌细胞包膜包含一个名为CTPA的C末端加工蛋白酶（CTP），该蛋白酶 对于急性感染至关重要。 CTPA采用了与Escherichia中唯一的CTP相似的作用 Coli，Prc，即使CTPA和PRC彼此截然不同。铜绿假单胞菌中的CTPA和PRC 大肠杆菌，降解酶，重塑细菌细胞壁。这很有趣，因为许多细菌 就像大肠杆菌只有一个CTP一样，铜绿假单胞菌有两个，第二个被称为PRC，因为它非常 类似于大肠杆菌。这引发了该探索性/发展建议的新问题：如果CTPA 达到了中国大肠杆菌中的角色，那么中国在PA中会做什么？已提出中国割伤 负调节蛋白粘膜，触发细胞外多糖的产生和表型 与囊性纤维化患者的预后不良有关。但是，既没有粘膜或任何其他铜绿假单胞菌 蛋白质已被证明是PRC底物。从我们的初步数据中，我们提出了一个令人兴奋的 PRC和CTPA对至少一个PG交联水解酶的差分控制的新模型。一起 通过我们的其他观察表明，中国会影响细胞壁，这支持了我们的中心假设，这是 中国的裂解裂解了参与细胞壁代谢的重要蛋白质，这可能是间接的 对抗sigma因子粘液的裂解的影响。为了检验这一假设，我们将：（1）确定PRC和PRC是否是否 CTPA在降解常见底物方面发挥不同的作用，（2）建立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，保守的理解 几乎所有细菌都很重要的过程。它还将提供第一个清晰的见解 PA，以及影响藻酸盐生物合成，粘液转化和细胞壁特征的机制 这会影响人类健康。了解这些机制可能最终有助于发展新的 针对这种普遍，危险且非常昂贵的人类病原体的治疗策略。