...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Proceedings of the National Academy of Sciences of the United States of America >Fluid dynamics and noise in bacterial cell-cell and cell-surface scattering
【24h】

Fluid dynamics and noise in bacterial cell-cell and cell-surface scattering

机译：细菌细胞-细胞和细胞表面散射中的流体动力学和噪声

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Bacterial processes ranging from gene expression to motility and biofilm formation are constantly challenged by internal and exter nal noise. While the importance of stochastic fluctuations has been appreciated for chemotaxis, it is currently believed that determinis tic long-range fluid dynamical effects govern cell-cell and cell surface scattering—the elementary events that lead to swarming and collective swimming in active suspensions and to the for mation of biofilms. Here, we report direct measurements of the bacterial flow field generated by individual swimming Escherichia coli both far from and near to a solid surface. These experiments allowed us to examine the relative importance of fluid dynamics and rotational diffusion for bacteria. For cell-cell interactions it is shown that thermal and intrinsic stochasticity drown the effects of long-range fluid dynamics, implying that physical interactions between bacteria are determined by steric collisions and near-field lubrication forces. This dominance of short-range forces closely links collective motion in bacterial suspensions to self-organization in driven granular systems, assemblages of biofilaments, and ani mal flocks. For the scattering of bacteria with surfaces, long-range fluid dynamical interactions are also shown to be negligible before collisions; however, once the bacterium swims along the surface within a few microns after an aligning collision, hydrodynamic effects can contribute to the experimentally observed, long resi dence times. Because these results are based on purely mechanical properties, they apply to a wide range of microorganisms.
机译：从基因表达到活力和生物膜形成的细菌过程不断受到内部和外部噪声的挑战。尽管随机波动对于趋化性的重要性已得到认可，但目前认为，决定性的远程流体动力学效应决定着细胞-细胞和细胞表面的散射，这些基本事件导致主动悬浮液中的群体和集体游泳。用于生物膜的成像。在这里，我们报告了直接测量远离和靠近固体表面的单个游泳大肠杆菌产生的细菌流场的情况。这些实验使我们能够研究流体动力学和旋转扩散对细菌的相对重要性。对于细胞间相互作用，表明热和固有的随机性淹没了远程流体动力学的影响，这意味着细菌之间的物理相互作用是由空间碰撞和近场润滑力决定的。这种短距离作用力的优势将细菌悬浮液中的集体运动与驱动颗粒系统，生物丝的组合和动物群的自组织紧密联系在一起。对于细菌在表面的散布，在碰撞之前，远距离流体动力学相互作用也可以忽略不计。然而，一旦细菌在对准碰撞后沿表面在几微米内游动，流体动力学效应可能有助于实验观察到较长的驻留时间。因为这些结果是基于纯粹的机械特性，所以它们适用于广泛的微生物。

著录项

  • 来源
  • 作者

    Knut Drescher; Joern Dunkel; Luis H. Cisneros; Sujoy Ganguly; Raymond E. Goldstein;

  • 作者单位

    Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 OWA, United Kingdom;

    Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 OWA, United Kingdom;

    Department of Physics, University of Arizona, 1118 East 4th Street, Tucson, AZ 85721;

    Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 OWA, United Kingdom;

    Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 OWA, United Kingdom;

  • 收录信息 美国《科学引文索引》(SCI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    low reynolds number hydrodynamics; microswimmers;

    机译：低雷诺数流体动力学;微泳;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号