Unraveling biofilm matrix composition, architecture, and function

揭示生物膜基质的组成、结构和功能

• 批准号: 2001189
• 负责人: Lynette Cegelski
• 金额: $ 100万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2001189&HistoricalAwards=false
• 关键词: Unraveling; biofilm; matrix; composition; architecture

Bacteria are essential to life as we know it and colonize and thrive in astonishing environments, ranging from within the human host to the acidic microbial mats in Yellowstone and industrial oil pipelines. The propensity for bacteria to form multicellular communities termed biofilms far exceeds the tendency to persist in suspension. Bacteria secrete and surround themselves with molecular polymers as building materials to enmesh and protect resident bacteria in slime-like assemblies. The PI’s recent work revealed the assembly of extraordinary mechanically robust basket-like architectures surrounding E. coli cells in biofilms and led to the discovery of a new chemical structure never before observed in nature within these baskets. Cellulose is the most abundant biopolymer on Earth, present in the cell walls of plants and trees, leading to wood, paper, and cotton products. Other industries also employ methods to modify standard cellulose through synthetic routes for desirable properties and are used as food additives and in membrane and biotechnology applications. E. coli produces its own uniquely modified form of cellulose with phosphoethanolamine groups through newly defined molecular machinery. This project tackles crucial questions involving nature’s phosphoethanolamine (pEtN) cellulose: its modification patterning, its physical properties and potential for application in new industrial materials, and the molecular basis for the assembly of the full polysaccharide-protein nanocomposite structures. This project will fuel new research directions with implications for bacterial physiology; glycobiology; and industrial applications including the production of new materials and uses in renewable energy. The PI communicates scientific concepts and discoveries through scientific and educational research articles targeted to broad audiences. This project will train undergraduate and graduate students, particularly those from groups under-represented in STEM. The PI is designing coursework changes to introduce more quantitative concepts and hands-on course-based undergraduate research experiences (CUREs) into undergraduate chemistry courses.This project will integrate biochemical analysis with characterization of polymer strength and materials properties, electron microscopy, fluorescence microscopy, solid-state NMR spectroscopy and mass spectrometry to: (1) deliver a fundamental understanding of the molecular patterning and physical properties of the zwitterionic phosphoethanolamine cellulose; (2) determine the influence of the cellulose modification on the Velcro-like association of curli at the bacterial cell surface; (3) define atomic-level parameters corresponding to molecular interactions between curli and pEtN cellulose in native bacterial composites in situ and highly tuned complexes formed in vitro. In addition to revealing the fundamental chemical principles underlying biofilm matrix assemblies, the work will introduce new methods for the production of pEtN cellulose and isotopically labeled matrix materials, and provide unprecedented atomic- level analysis of insoluble matrix materials that pose a challenge to analysis by conventional methods. The project may serve to reveal a new paradigm for understanding the molecular basis of other amyloid- polysaccharide interactions, prevalent not only in microorganisms but also in eukaryotic cell systems and should inspire the search for alternately modified celluloses and polysaccharides. This project is supported by the Molecular Biophysics Cluster of the Molecular and Cellular Biosciences Division in the Directorate for Biological Sciences.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

正如我们所知，细菌对生命至关重要，它们在令人惊讶的环境中繁衍生息，从人类宿主体内到黄石公园的酸性微生物垫和工业石油管道。细菌形成被称为生物膜的多细胞群落的倾向远远超过在悬浮液中持续存在的倾向。细菌分泌和周围的分子聚合物作为建筑材料，以黏液状组件缠绕和保护常驻细菌。PI最近的工作揭示了在生物膜中围绕大肠杆菌细胞的特殊机械坚固的篮子状结构的组装，并导致在这些篮子中发现了以前从未在自然界中观察到的新化学结构。纤维素是地球上最丰富的生物聚合物，存在于植物和树木的细胞壁中，用于生产木材、纸张和棉花产品。其他工业也采用各种方法，通过合成途径对标准纤维素进行改性，使其具有理想的性能，并用作食品添加剂、膜和生物技术应用。大肠杆菌通过新定义的分子机制产生其独特的带有磷酸乙醇胺基团的纤维素修饰形式。该项目解决了涉及自然界磷酸乙醇胺（pEtN）纤维素的关键问题：它的修饰模式，它的物理性质和在新工业材料中的应用潜力，以及组装完整的多糖-蛋白质纳米复合结构的分子基础。该项目将为细菌生理学提供新的研究方向；糖生物学;工业应用，包括新材料的生产和可再生能源的使用。PI通过针对广大受众的科学和教育研究文章传播科学概念和发现。该项目将培训本科生和研究生，特别是那些来自STEM中代表性不足的群体的学生。PI正在设计课程改革，在本科化学课程中引入更多的定量概念和基于实践的本科研究经验（CUREs）。该项目将整合生物化学分析、聚合物强度和材料特性表征、电子显微镜、荧光显微镜、固态核磁共振波谱和质谱，以：(1)提供对两性离子磷酸乙醇胺纤维素的分子模式和物理特性的基本理解；(2)测定纤维素改性对细菌细胞表面curli类魔术贴结合体的影响；(3)确定原生细菌复合材料和体外形成的高调谐配合物中curli和pEtN纤维素分子相互作用的原子水平参数。除了揭示生物膜基质组合的基本化学原理外，这项工作还将引入生产pEtN纤维素和同位素标记基质材料的新方法，并提供前所未有的不溶性基质材料的原子水平分析，这对传统方法的分析构成了挑战。该项目可能有助于揭示其他淀粉样蛋白-多糖相互作用的分子基础的新范式，不仅在微生物中普遍存在，而且在真核细胞系统中也很普遍，并且应该激发对交替修饰的纤维素和多糖的研究。该项目得到了生物科学理事会分子和细胞生物科学部分子生物物理组的支持。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Chemical and Molecular Composition of the Chrysalis Reveals Common Chitin-Rich Structural Framework for Monarchs and Swallowtails

• DOI: 10.1016/j.jmb.2022.167456
• 发表时间: 2022-02-05
• 期刊: JOURNAL OF MOLECULAR BIOLOGY
• 影响因子: 5.6
• 作者: Goularte, Nicolette F.;Kallem, Till;Cegelski, Lynette
• 通讯作者: Cegelski, Lynette

Molecular organization of the E. coli cellulose synthase macrocomplex.

• DOI: 10.1038/s41594-021-00569-7
• 发表时间: 2021-03
• 期刊: NATURE STRUCTURAL & MOLECULAR BIOLOGY
• 影响因子: 16.8
• 作者: Acheson, Justin F.;Ho, Ruoya;Goularte, Nicolette F.;Cegelski, Lynette;Zimmer, Jochen
• 通讯作者: Zimmer, Jochen

Variation in the ratio of curli and phosphoethanolamine cellulose associated with biofilm architecture and properties

• DOI: 10.1002/bip.23395
• 发表时间: 2020-09-07
• 期刊: BIOPOLYMERS
• 影响因子: 2.9
• 作者: Jeffries, Jamie;Thongsomboon, Wiriya;Cegelski, Lynette
• 通讯作者: Cegelski, Lynette

Nordihydroguaiaretic Acid (NDGA) Inhibits CsgA Polymerization, Bacterial Amyloid Biogenesis, and Biofilm Formation

去甲二氢愈创木酸 (NDGA) 抑制 CsgA 聚合、细菌淀粉样蛋白生物发生和生物膜形成

• DOI: 10.1002/cbic.202300266
• 发表时间: 2023
• 期刊: ChemBioChem
• 影响因子: 3.2
• 作者: Visser, Joshua A.;Yager, Deborah;Chambers, Schuyler A;Lim, Ji Youn;Cao, Xujun;Cegelski, Lynette
• 通讯作者: Cegelski, Lynette

Mechanochemical synthesis of an elusive fluorinated polyacetylene

• DOI: 10.1038/s41557-020-00608-8
• 发表时间: 2020-12-22
• 期刊: NATURE CHEMISTRY
• 影响因子: 21.8
• 作者: Boswell, Benjamin R.;Mansson, Carl M. F.;Burns, Noah Z.
• 通讯作者: Burns, Noah Z.