Agent-based modeling of stress anisotropy driven nematic ordering in growing biofilms.
Agent-based modeling of stress anisotropy driven nematic ordering in growing biofilms.
复制标题
基于代理的生物膜生长中应力各向异性驱动的向列排序建模。
DOI：
10.1039/d3sm01535a
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发表时间：
2024
期刊：
影响因子：
3.4
通讯作者：
Zhang,Sulin
中科院分区：
文献类型：
--
作者：
Li,Changhao;Nijjer,Japinder;Feng,Luyi;Zhang,Qiuting;Yan,Jing;Zhang,Sulin
活的活跃集体已经进化出了非凡的自我模式能力，以适应对他们的成长和生存至关重要的物理和生物约束。然而，复杂的多细胞模式从单个创始细胞中出现的复杂过程仍然难以捉摸。在这项研究中，我们利用基于代理的模型，通过单细胞显微镜成像验证，跟踪三维（3D）形态动力学的细胞内生长的细菌生物膜包裹琼脂糖凝胶。受限的生长条件引起生物膜内的时空异质应力景观。在生物膜的核心中，高流体静力学和低剪切应力占主导地位，细胞包装出现无序。相比之下，在凝胶-细胞界面附近，出现高剪切应力和低静水应力的状态，从而驱动非线性有序化，尽管剪切应力松弛具有固有的时间延迟。引人注目的是，我们观察到一个强大的时空相关性应力各向异性和这些密闭的生物膜内的有序。这种相关性表明了一种机制，即应力各向异性在控制细胞的空间组织中起着关键作用。在有限的生物膜中，应力各向异性和细胞有序之间的相互作用为创新的3D机械引导图案化技术开辟了新的途径，用于生活的活性集体，这为广泛的环境和生物医学应用带来了重大的希望。
Living active collectives have evolved with remarkable self-patterning capabilities to adapt to the physical and biological constraints crucial for their growth and survival. However, the intricate process by which complex multicellular patterns emerge from a single founder cell remains elusive. In this study, we utilize an agent-based model, validated through single-cell microscopy imaging, to track the three-dimensional (3D) morphodynamics of cells within growing bacterial biofilms encased by agarose gels. The confined growth conditions give rise to a spatiotemporally heterogeneous stress landscape within the biofilm. In the core of the biofilm, where high hydrostatic and low shear stresses prevail, cell packing appears disordered. In contrast, near the gel–cell interface, a state of high shear stress and low hydrostatic stress emerges, driving nematic ordering, albeit with a time delay inherent to shear stress relaxation. Strikingly, we observe a robust spatiotemporal correlation between stress anisotropy and nematic ordering within these confined biofilms. This correlation suggests a mechanism whereby stress anisotropy plays a pivotal role in governing the spatial organization of cells. The reciprocity between stress anisotropy and cell ordering in confined biofilms opens new avenues for innovative 3D mechanically guided patterning techniques for living active collectives, which hold significant promise for a wide array of environmental and biomedical applications.