Bacterial biofilms can cause medical problems and issues in technical systems. While a large body of knowledge exists on the phenotypes of planktonic and of sessile cells in mature biofilms, our understanding of what happens when bacteria change from the planktonic to the sessile state is still very incomplete. Fundamental questions are unanswered: for instance, how do bacteria sense that they are in contact with a surface, and what are the very initial cellular responses to surface contact. Here, we review the current knowledge on the signals that bacteria could perceive once they attach to a surface, the signal transduction systems that could be involved in sensing the surface contact and the cellular responses that are triggered as a consequence to surface contact ultimately leading to biofilm formation. Finally, as the main obstacle in investigating the initial responses to surface contact has been the difficulty to experimentally study the dynamic response of single cells upon surface attachment, we also review recent experimental approaches that could be employed to study bacterial surface sensing, which ultimately could lead to an improved understanding of how biofilm formation could be prevented.

中文翻译：

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细菌如何识别和响应表面接触。

细菌生物膜会引起医学问题以及技术系统中的问题。尽管关于成熟生物膜中浮游生物和无柄细胞的表型存在大量知识，但我们对细菌从浮游状态转变为无柄状态时会发生什么的理解仍然非常不完整。基本问题尚未解决：例如，细菌如何感觉到它们与表面接触，以及最初对表面接触的细胞反应是什么？在这里，我们回顾了有关细菌一旦附着到表面便能感知到的信号的当前知识，可能涉及传感表面接触的信号转导系统以及由于表面接触而最终触发的细胞反应，最终导致生物膜形成。最后，