Borer Benedict, Ciccarese Davide, Johnson David, Or Dani
Department of Environmental Systems Science, ETH Zürich, 8092, Zürich, Switzerland.
Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600, Dübendorf, Switzerland.
Commun Biol. 2020 Nov 18;3(1):685. doi: 10.1038/s42003-020-01409-y.
Evidence suggests that bacterial community spatial organization affects their ecological function, yet details of the mechanisms that promote spatial patterns remain difficult to resolve experimentally. In contrast to bacterial communities in liquid cultures, surface-attached range expansion fosters genetic segregation of the growing population with preferential access to nutrients and reduced mechanical restrictions for cells at the expanding periphery. Here we elucidate how localized conditions in cross-feeding bacterial communities shape community spatial organization. We combine experiments with an individual based mathematical model to resolve how trophic dependencies affect localized growth rates and nucleate successful cell lineages. The model tracks individual cell lineages and attributes these with trophic dependencies that promote counterintuitive reproductive advantages and result in lasting influences on the community structure, and potentially, on its functioning. We examine persistence of lucky lineages in structured habitats where expansion is interrupted by physical obstacles to gain insights into patterns in porous domains.
有证据表明细菌群落的空间组织会影响其生态功能，然而，促进空间模式形成的机制细节在实验上仍难以解析。与液体培养中的细菌群落不同，表面附着的范围扩展促进了生长群体的遗传隔离，使处于扩展边缘的细胞能优先获取营养，并减少机械限制。在此，我们阐明了交叉喂养细菌群落中的局部条件如何塑造群落空间组织。我们将实验与基于个体的数学模型相结合，以解析营养依赖如何影响局部生长速率并形成成功的细胞谱系。该模型追踪个体细胞谱系，并赋予其营养依赖关系，这些依赖关系促进了违反直觉的繁殖优势，并对群落结构乃至其功能产生持久影响。我们研究了在结构化栖息地中幸运谱系的持久性，在这些栖息地中，扩展因物理障碍而中断，以深入了解多孔区域中的模式。
