Cell-Wall Recycling and Nexus to Antibiotic Resistance

细胞壁回收及其与抗生素耐药性的关系

• 批准号: 10627796
• 负责人: Shahriar Mobashery
• 金额: $ 38.63万
• 依托单位: UNIVERSITY OF NOTRE DAME
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10627796
• 关键词: Antibiotic Resistance; Antibiotics; Applications Grants; Bacteria; Biochemical Process; Carbapenems; Cell Wall; Cephalosporins; Clinical; Complex; Cytoplasm; Enterobacteriaceae; Enzymes; Event; Future; Genetic Transcription; Gram-Negative Bacteria; Gram-Negative Bacterial Infections; Growth; Host resistance; Individual; Interruption; Knowledge; Lead; Link; Lytic; Mission; Natural Products; Outcome; Penicillins; Physiological Processes; Process; Proteins; Pseudomonas aeruginosa; Reaction; Recycling; Resistance; Science; Structure; Study Subject; System; beta-Lactam Resistance; beta-Lactamase; beta-Lactams; cell injury; chemical reaction; expectation; human pathogen; novel strategies; pathogen; periplasm; repaired; resistance mechanism; response

Project Summary/Abstract Cell-wall recycling is a fundamental process in bacteria, whereby it allows for remodeling of the cell wall in the course of the normal growth and in response to antibiotics that inflict damage to the cell wall for their mechanisms of action. Enterobacteriaceae and Pseudomonas aeruginosa (subject of this grant application) sense damage inflicted to their cell wall by β-lactam antibiotics. The sensing event is linked to cell-wall recycling, which leads to the formation of cell-wall-based natural products known as muropeptides. Certain muropeptides are internalized to the cytoplasm, where they induce the bacterial response to the antibiotic (antibiotic-resistance mechanisms). This process has led to obsolescence of many of the β-lactam antibiotics against Gram-negative bacteria. My lab has studied this system for the past several years and what I disclose in this MIRA application is the path that the lab will chart in the immediate future. I propose to study the periplasmic complexes involving lytic transglycosylases (LTs), which turn over the cell wall for the purpose of recycling or in response to damage by antibiotics. My lab has documented that there are 11 known LTs in P. aeruginosa, whose individual reactions with the cell wall have been described by us. These enzymes are proposed to be involved in complexes with other proteins within the periplasm, whose identities are not known and represent a major gap in our knowledge of cell-wall processes. Whereas all the functions of LTs are not understood, one is repair of cell wall upon exposure of bacteria to β-lactam antibiotics. Muropeptides are the degradation products of cell-wall recycling, which are internalized to the cytoplasm for this purpose. As an offshoot of the recycling events, certain muropetides activate the AmpR transcriptional regulator in expression of the AmpC β-lactamase, the resistance determinant for β-lactam antibiotics. We will study the interactions of the key mutropeptides with the AmpR protein in elucidating the system. Furthermore, four additional cytoplasmic enzymes that have been identified in P. aeruginosa for the key events of the muropeptide recycling will be investigated for their chemical reactions, the details of the catalytic cycles and for their structures. I anticipate that the successful completion of this proposed science will not only lead to the elucidation of these important events regulating the cell wall, but also will identify opportunities for their interruption as a means to circumventing the elaborate mechanism of β-lactam resistance that Gram-negative bacteria have evolved. These complex events are poorly understood, and they will be studied in detail in my lab in the course of the proposed reseach.

项目概要/摘要 细胞壁回收是细菌的一个基本过程，通过它可以重塑细菌中的细胞壁。 正常生长过程以及对抗生素造成的细胞壁损伤的反应 作用机制。肠杆菌科和铜绿假单胞菌（本拨款申请的主题） 感知β-内酰胺抗生素对其细胞壁造成的损伤，感知事件与细胞壁有关。 回收，从而形成基于细胞壁的天然产物，称为某些壁肽。 壁肽内化到细胞质中，诱导细菌对抗生素的反应 （抗生素耐药机制）。这个过程导致许多β-内酰胺抗生素的淘汰。 我的实验室在过去的几年里研究了这个系统，以及我所披露的内容。 在这个 MIRA 应用程序中，我建议实验室在不久的将来进行研究。 涉及裂解性转糖基酶 (LT) 的周质复合物，其翻转细胞壁以实现 我的实验室记录了 P. 中存在 11 种已知的 LT。 铜绿假单胞菌，我们已经描述了这些酶与细胞壁的单独反应。 提议参与与周质内其他蛋白质的复合物，其身份尚不清楚 并代表了我们对细胞壁过程的了解的一个主要空白，但 LT 的所有功能都不是。 据了解，其中之一是细菌接触β-内酰胺类抗生素后细胞壁的修复。 细胞壁回收的降解产物，为此目的而内化到细胞质中。 作为回收事件的分支，某些 muropetides 在表达中激活 AmpR 转录调节因子 AmpC β-内酰胺酶是 β-内酰胺类抗生素的耐药性决定因素，我们将研究它们之间的相互作用。 与 AmpR 蛋白一起阐明该系统的关键互肽。此外，另外还有四种 已在铜绿假单胞菌中鉴定出参与胞肽关键事件的胞质酶 将研究回收的化学反应、催化循环的细节及其 我预计这项拟议的科学的成功完成不仅会导致 阐明这些调节细胞壁的重要事件，同时也将确定它们的机会 中断作为规避革兰氏阴性菌所产生的β-内酰胺耐药的复杂机制的一种手段 人们对这些复杂的事件知之甚少，我将在我的文章中详细研究它们。 实验室在拟议的研究过程中。

项目成果

Amber-codon suppression for spatial localization and in vivo photoaffinity capture of the interactome of the Pseudomonas aeruginosa rare lipoprotein A lytic transglycosylase.

琥珀密码子抑制用于铜绿假单胞菌稀有脂蛋白 A 裂解转糖基酶相互作用组的空间定位和体内光亲和捕获。

• 发表时间: 2023-10
• 作者: Avila;Hoshino, Hidekazu;Horsman, Mark E;Nguyen, Van T;Qian, Yuanyuan;Feltzer, Rhona;Kim, Choon;Hu, Daniel D;Champion, Matthew M;Fisher, Jed F;Mobashery, Shahriar
• 通讯作者: Mobashery, Shahriar

Structure-based inhibitor design for reshaping bacterial morphology.

基于结构的抑制剂设计，用于重塑细菌形态。

• 发表时间: 2022-04-28
• 影响因子: 5.9
• 作者: Choi, Yuri;Park, Ji Su;Kim, Jinshil;Min, Kyungjin;Mahasenan, Kiran;Kim, Choon;Yoon, Hye;Lim, Sewon;Cheon, Dae Hee;Lee, Yan;Ryu, Sangryeol;Mobashery, Shahriar;Kim, B Moon;Lee, Hyung Ho
• 通讯作者: Lee, Hyung Ho

Catalytic process of anhydro-N-acetylmuramic acid kinase from Pseudomonas aeruginosa.

铜绿假单胞菌脱水-N-乙酰胞壁酸激酶的催化过程。

• 发表时间: 2023-10
• 作者: El;Jiménez;Feltzer, Rhona;Martin;Karri, Bhaskara Rao;Ramachandran, Balajee;Kim, Choon;Fisher, Jed F;Hermoso, Juan A;Mobashery, Shahriar
• 通讯作者: Mobashery, Shahriar