Cannibalism in Bacillus subtilis colonies: Role of programmed cell death in shaping and functionalizing differentiated multicellular populations

枯草芽孢杆菌菌落中的同类相食：程序性细胞死亡在分化多细胞群体的形成和功能化中的作用

• 批准号: 504017689
• 负责人: Professor Dr. Klaus Dreisewerd
• 金额: --
• 依托单位: Professur für Allgemeine Mikrobiologie
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/504017689?language=en
• 关键词: Cannibalism; Bacillus; subtilis; colonies; Role

Cannibalism is a unique bacterial form of programmed cell death (PCD) that links multicellular differentiation to endospore formation in Bacillus subtilis. On solid surfaces, undomesticated strains form intricately structured colonies, in which phenotypically different cell types are spatiotemporally coordinated to form robust microbial tissues and fruiting bodies. These structures provide a multicellular form for controlling population expansion, balancing growth with survival, and ultimately culminating in the formation of dormant endospores. Cannibalism is based on the production of at least three toxins, the sporulation killing factor SKF, the sporulation delay protein SDP and the epipeptide EPE. Cannibalism seems to represent a central checkpoint in tissue formation, since it (i) provides resources to either delay or ultimately fuel sporulation, (ii) structures and functionalizes the colonies, and might ultimately serve to (iii) balance the ratio of different cell types in structured multicellular populations. In this joint project, we aim at unravelling the role of PCD, mediated by cannibalism toxins and other secondary metabolites, for the structure and function of differentiated B. subtilis colonies. We aim at mechanistically understanding cannibalism toxin action both in 2D microcolonies at single-cell resolution, and in 3D differentiated macrocolonies (Mascher).Cannibalism toxin production in colonies will also serve as a biological model system to apply and develop microbial MALDI mass spectrometry imaging (MSI), a core technology of this priority program. This powerful technique will be developed to enable studying the complex chemistry of bacterial colonies (cm range) in time and 3D space at single cell resolution (µm range). Combining MSI with further imaging modalities, including life cell imaging, multi-parameter flow cytometry and single cell transcriptomics will allow obtaining a comprehensive spatiotemporal map of microbial tissue dynamics and structure at unprecedented resolution. For developing MALDI-MSI (Dreisewerd), the current set-up for 2D topview and cross-section analysis will be optimized and the range of compounds detected will be expanded. A protocol for incorporating transmission geometries will be established by analyzing vertical thin-sections of colonies at µm resolution. Combined with 2D topview, this will allow analyzing bacterial colonies in 3D at high resolution down to single-cell level. Moreover, the established MALDI-MSI procedures shall be applied beyond B. subtilis, e.g. for studying PCD in E. coli and analyzing chemical communication in P. aeruginosa biofilms.

自食是枯草芽孢杆菌中一种独特的程序性细胞死亡（PCD）形式，它将多细胞分化与内生孢子形成联系起来。在固体表面上，未驯化的菌株形成复杂结构的菌落，其中表型不同的细胞类型在时空上协调以形成稳健的微生物组织和子实体。这些结构提供了一种多细胞形式，用于控制种群扩张，平衡生长与存活，并最终形成休眠的内生孢子。同类相食是基于至少三种毒素的产生，孢子形成杀伤因子SKF、孢子形成延迟蛋白SDP和表肽EPE。同类相食似乎代表了组织形成中的一个中心检查点，因为它（i）提供了延迟或最终促进孢子形成的资源，（ii）使菌落结构化和功能化，并可能最终用于（iii）平衡结构化多细胞群体中不同细胞类型的比例。在这个联合项目中，我们的目标是解开PCD的作用，介导的同类相食毒素和其他次级代谢产物，分化的B的结构和功能。枯草杆菌菌落。我们的目标是在单细胞分辨率的2D小菌落和3D分化的大菌落（Mascher）中机械地理解食人毒素的作用。菌落中的食人毒素生产也将作为应用和开发微生物MALDI质谱成像（MSI）的生物模型系统，这是该优先计划的核心技术。这种强大的技术将被开发，以使研究细菌菌落的复杂化学（厘米范围）在时间和3D空间在单细胞分辨率（微米范围）。 将MSI与进一步的成像方式（包括生命细胞成像、多参数流式细胞术和单细胞转录组学）相结合，将允许以前所未有的分辨率获得微生物组织动力学和结构的全面时空图。为了开发MALDI-MSI（Dreisewerd），将优化当前的2D顶视图和横截面分析设置，并扩大检测化合物的范围。将通过以µm分辨率分析菌落的垂直薄切片来建立用于合并传输几何形状的方案。结合2D俯视图，这将允许以高分辨率分析3D细菌菌落，直至单细胞水平。此外，已建立的MALDI-MSI程序应适用于B以外。subtilis，例如用于研究E.大肠杆菌中的化学物质，并分析铜绿假单胞菌生物膜中的化学通讯。