Mechanism of Cell Division in Prokaryotes

原核生物细胞分裂的机制

• 批准号: 9889135
• 负责人: Jodi Lynn Camberg
• 金额: $ 28.14万
• 依托单位: UNIVERSITY OF RHODE ISLAND
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9889135
• 关键词: ATP Hydrolysis; ATP phosphohydrolase; Address; Antibiotic Resistance; Antibiotics; Antimicrobial Resistance; Architecture; Bacteria; Bacterial Antibiotic Resistance; Binding; Binding Sites; Biochemical; Biological Assay; Biophysics; Cell division; Cell membrane; Cells; Cessation of life; Collaborations; Complex; Development; Ensure; Escherichia coli; Exhibits; Future; Genetic; Genetic Screening; Goals; Growth; Homologous Gene; In Vitro; Infection; Knowledge; Liposomes; Location; Maps; Membrane; Mind; Mitosis; Modeling; Molecular; Mothers; Nucleotides; Pathway interactions; Phenotype; Phospholipid Interaction; Phospholipids; Physiological; Polymers; Process; Prokaryotic Cells; Proteins; Public Health; Regulation; Reporting; Role; Security; Site; Structure; System; Tubulin; United States; Universities; base; combat; constriction; copolymer; daughter cell; design; enzyme activity; experimental study; global health; improved; in vivo; insight; novel; polymerization; prevent; protein function; protein structure; reconstitution; recruit; screening; therapeutic target; tool; z-ring

PROJECT SUMMARY The cell division pathway in bacteria is a fundamental and highly conserved physiological pathway that enables a single mother cell to divide into two identical daughter cells by mitosis. This pathway is essential for proliferation and colonization by bacteria. A detailed understanding of this pathway will provide fundamental, molecular knowledge that will improve the future design of new antibiotics and therapeutics targeting this pathway. Here, we propose experiments to uncover biochemical and functional roles of several key cell division proteins. Early in the cell division pathway, a protein structure with ring-like architecture, called the Z-ring, assembles at the site of cell division. Multiple protein systems ensure that assembly of the ring occurs at midcell, adjacent to the membrane and away from the nucleoid. In Escherichia coli, the Min system, which includes MinC, MinD, and MinE, exhibits polar oscillation and antagonizes FtsZ-ring assembly at the cell poles. MinC directly associates with FtsZ to inhibit FtsZ polymerization, thus preventing Z-ring assembly, and forms a complex with MinD, which establishes the cellular location of MinC. As FtsZ polymerization is antagonized at the poles in vivo by MinC, FtsZ polymers coalesce at midcell to form the Z-ring, tethered to the inner leaflet of the cytoplasmic membrane through direct interactions with membrane-associated ATPase FtsA. Once the mature Z-ring assembles in vivo, FtsZ polymerization is antagonized by a cellular network of proteins that modulate FtsZ polymer assembly. To understand the biochemical mechanisms of systems that regulate Z-ring assembly in vitro and in vivo, we will investigate direct interactions between FtsZ and FtsZ-interacting proteins and probe the functional activities of FtsZ-interacting proteins, including FtsA, MinC and ZapE. We are proposing experiments to elucidate the biochemical mechanisms of FtsA, including ATP utilization, oligomerization, phospholipid binding, recruitment of FtsZ, regulation of FtsZ polymerization, and interactions with late stage division proteins. To understand how MinC interacts with FtsZ and forms copolymers with MinD we are incorporating new genetic tools, phenotypic screens and in vitro biochemical assays to map the FtsZ binding site on MinC, probe activation of MinD, and evaluate the role of MinCD polymers on FtsZ assembly in vivo and in vitro. We will also investigate how ZapE, a recently reported cell division ATPase, impacts division and FtsZ in vitro and in vivo and probe ZapE structure. Together, these studies will uncover key mechanistic steps that are essential for cell division and provide insight to advance current models for Z-ring assembly and constriction based on biophysical interactions.

项目概要 细菌的细胞分裂途径是一条基本且高度保守的生理途径 这使得单个母细胞能够通过有丝分裂分裂成两个相同的子细胞。这条途径是 对于细菌的增殖和定植至关重要。对该途径的详细了解将 提供基础分子知识，以改进新抗生素的未来设计 针对该途径的治疗。在这里，我们提出实验来揭示生化和 几种关键细胞分裂蛋白的功能作用。在细胞分裂途径的早期，一种蛋白质 具有环状结构的结构，称为 Z 环，在细胞分裂部位组装。多种的 蛋白质系统确保环的组装发生在细胞中部，靠近膜并远离 来自核仁。在大肠杆菌中，Min 系统（包括 MinC、MinD 和 MinE）表现出 极振荡并拮抗细胞极处的 FtsZ 环组件。 MinC 直接关联 FtsZ 抑制 FtsZ 聚合，从而阻止 Z 环组装，并与 MinD 形成复合物， 它确定了 MinC 的蜂窝位置。由于 FtsZ 聚合在两极被拮抗 Vivo by MinC，FtsZ 聚合物在细胞中部聚结形成 Z 形环，拴在细胞的内叶上 通过与膜相关的 ATP 酶 FtsA 直接相互作用来抑制细胞质膜。一旦 成熟的 Z 环在体内组装，FtsZ 聚合被蛋白质的细胞网络拮抗 调节 FtsZ 聚合物组装。 了解调节 Z 环体外组装系统的生化机制 在体内，我们将研究 FtsZ 和 FtsZ 相互作用蛋白之间的直接相互作用 探测 FtsZ 相互作用蛋白的功能活性，包括 FtsA、MinC 和 ZapE。我们是 提出实验来阐明 FtsA 的生化机制，包括 ATP 利用， 寡聚化、磷脂结合、FtsZ 募集、FtsZ 聚合调节，以及 与晚期分裂蛋白的相互作用。了解 MinC 如何与 FtsZ 和表单交互 与 MinD 的共聚物，我们正在整合新的遗传工具、表型筛选和体外 生化检测以绘制 MinC 上的 FtsZ 结合位点、探针激活 MinD 并评估 MinCD 聚合物对体内和体外 FtsZ 组装的作用。我们还将研究 ZapE（一个 最近报道了细胞分裂 ATP 酶，在体外和体内影响分裂和 FtsZ 并探测 ZapE 结构。这些研究将共同​​揭示细胞分裂所必需的关键机制步骤 并提供见解，以推进基于 Z 形环组装和收缩的当前模型 生物物理相互作用。