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.

项目摘要 细菌细胞分裂途径是一条基本的、高度保守的生理途径 使单个母细胞通过有丝分裂分裂成两个相同的子细胞。该途径 对于细菌的增殖和定居是必需的。详细了解这一途径将 提供基础的，分子知识，将改善新抗生素的未来设计， 针对这一途径的治疗方法。在这里，我们提出实验来揭示生物化学和 几种关键细胞分裂蛋白的功能作用。在细胞分裂的早期，一种蛋白质 具有环状结构的结构，称为Z环，在细胞分裂的部位组装。多 蛋白质系统确保环的组装发生在中间细胞，靠近膜并远离 从类核中在大肠杆菌中，包括MinC、MinD和MinE的Min系统表现出 极性振荡和拮抗FtsZ-环组装在细胞两极。MinC直接与 FtsZ抑制FtsZ聚合，从而防止Z环组装，并与MinD形成复合物， 其建立MinC的蜂窝位置。由于FtsZ聚合在细胞中的两极被拮抗， 在体内通过MinC，FtsZ聚合物在中间细胞处聚结以形成Z环，栓系到细胞的内小叶。 通过与膜相关ATP酶FtsA的直接相互作用，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 其调节FtsZ聚合物组装。 了解体外调节Z环组装的系统的生化机制 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， 探索FtsZ相互作用蛋白的功能活性，包括FtsA，MinC和ZapE。我们 提出实验来阐明FtsA的生化机制，包括ATP的利用， 寡聚化、磷脂结合、FtsZ的募集、FtsZ聚合的调节，以及 与后期分裂蛋白的相互作用。了解MinC如何与FtsZ相互作用并形成 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 生物化学测定以绘制MinC上的FtsZ结合位点，探测MinD的激活，并评估 MinCD聚合物在体内和体外对FtsZ组装的作用。我们还将调查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，并探针ZapE 结构总之，这些研究将揭示细胞分裂所必需的关键机制步骤 并提供洞察力，以推进Z形环组装和收缩的当前模型， 生物物理相互作用