Noncontact Cohesive Swimming of Bacteria in Two-Dimensional Liquid Films.
Noncontact Cohesive Swimming of Bacteria in Two-Dimensional Liquid Films.
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DOI：
10.1103/physrevlett.119.018101
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发表时间：
2017-07-07
影响因子：
8.6
通讯作者：
Wu Y
中科院分区：
文献类型：
--
作者：
Li Y;Zhai H;Sanchez S;Kearns DB;Wu Y
细菌在受限的二维环境中游泳在自然界和临床环境中是普遍存在的。表征在二维禁闭中游泳的细菌之间的个体相互作用将有助于理解不同的微生物过程，如细菌群和生物膜的形成。在这里，我们报告了鞭毛细菌在二维禁闭中的一种新的生物物理相互作用形式：当两个附近的细胞对齐它们的运动方向时，它们倾向于在没有直接细胞体接触的情况下进行粘性游泳，这是由于流体动力学相互作用而不是鞭毛缠绕的结果。我们进一步发现，细胞在内聚游动时具有更高的定向持久性，这可以使细胞的有效扩散率提高约3倍，这是计算模型预测的结果。作为环鞭毛细菌的一种保守行为，二维约束下的内聚游动可能是细菌群体集体运动和自组织的关键；它还可能促进细菌在非饱和土壤和感染间隙中的扩散。
Bacterial swimming in confined two-dimensional environments is ubiquitous in nature and in clinical settings. Characterizing individual interactions between swimming bacteria in 2D confinement will help to understand diverse microbial processes, such as bacterial swarming and biofilm formation. Here we report a novel form of biophysical interaction between flagellated bacteria in 2D confinement: When two nearby cells align their moving directions, they tend to engage in cohesive swimming without direct cell body contact, as a result of hydrodynamic interaction but not flagellar intertwining. We further found that cells in cohesive swimming move with higher directional persistence, which can increase the effective diffusivity of cells by ~3 times as predicted by computational modeling. As a conserved behavior for peritrichously flagellated bacteria, cohesive swimming in 2D confinement may be key to collective motion and self-organization in bacterial swarms; it may also promote bacterial dispersal in unsaturated soils and in interstitial space during infections.