Mechanical Resilience of Biofilms toward Environmental Perturbations Mediated by Extracellular Matrix
Mechanical Resilience of Biofilms toward Environmental Perturbations Mediated by Extracellular Matrix
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DOI：
10.1002/adfm.202110699
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发表时间：
2022-03
影响因子：
19
通讯作者：
Qiuting Zhang;Danh-Truong Nguyen;Jung-Shen B. Tai;XJ Xu;Japinder S. Nijjer;Xin Huang;Y. Li;Jing Yan
中科院分区：
文献类型：
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作者：
Qiuting Zhang;Danh-Truong Nguyen;Jung-Shen B. Tai;XJ Xu;Japinder S. Nijjer;Xin Huang;Y. Li;Jing Yan
生物膜是包埋在细胞外基质（ECM）中的细菌细胞的表面相关群落。生物膜细胞可以在各种动态环境中生存和茁壮成长，在医疗保健和工业中造成顽固的问题。从材料科学的角度来看，生物膜可以被认为是柔软的粘弹性材料，并表现出显着的机械弹性。生物膜如何实现对各种环境扰动的弹性仍不清楚，虽然ECM已被普遍认为发挥了关键作用。在这里，霍乱弧菌（Vc）被用来作为一种模式生物，通过系统地研究每个组成基质成分的作用，在非线性流变学制度的生物膜力学。结合诱变，流变学测量和分子动力学模拟，研究了各种突变生物膜的机械行为及其不同的机械表型，包括机械引导形态，非线性粘弹性行为以及从大剪切力和加热中恢复。结果表明，ECM聚合物网络通过响应于大的机械扰动提供机械弹性来保护嵌入的细胞免受环境挑战。这些发现为生物膜的结构-性质关系提供了物理见解，这些关系可以用于设计生物膜去除策略，或者更前瞻性地将生物膜设计为动态环境中有益的功能性软材料。
Biofilms are surface‐associated communities of bacterial cells embedded in an extracellular matrix (ECM). Biofilm cells can survive and thrive in various dynamic environments causing tenacious problems in healthcare and industry. From a materials science point of view, biofilms can be considered as soft, viscoelastic materials, and exhibit remarkable mechanical resilience. How biofilms achieve such resilience toward various environmental perturbations remain unclear, although ECM has been generally considered to play a key role. Here, Vibrio cholerae (Vc) is used as a model organism to investigate biofilm mechanics in the nonlinear rheological regime by systematically examining the role of each constituent matrix component. Combining mutagenesis, rheological measurements, and molecular dynamics simulations, the mechanical behaviors of various mutant biofilms and their distinct mechanical phenotypes including mechanics‐guided morphologies, nonlinear viscoelastic behavior, and recovery from large shear forces and heating are investigated. The results show that the ECM polymeric network protects the embedded cells from environmental challenges by providing mechanical resilience in response to large mechanical perturbation. The findings provide physical insights into the structure–property relationship of biofilms, which can be potentially employed to design biofilm removal strategies or, more forward‐looking, engineer biofilms as beneficial, functional soft materials in dynamic environments.