Budrene E O, Berg H C
Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Nature. 1995 Jul 6;376(6535):49-53. doi: 10.1038/376049a0.
Motile cells of Escherichia coli aggregate to form stable patterns of remarkable regularity when grown from a single point on certain substrates. Central to this self-organization is chemotaxis, the motion of bacteria along gradients of a chemical attractant that the cells themselves excrete. Here we show how these complex patterns develop. The long-range spatial order arises from interactions between two multicellular aggregate structures: a 'swarm ring' that expands radially, and focal aggregates that have lower mobility. Patterning occurs through alternating domination by these two sources of excreted attractant (which we identify here as aspartate). The pattern geometries vary in a systematic way, depending on how long an aggregate remains active; this depends, in turn, on the initial concentration of substrate (here, succinate).
当从某些底物上的单个点开始生长时，大肠杆菌的运动细胞会聚集形成具有显著规律性的稳定模式。这种自我组织的核心是趋化作用，即细菌沿着细胞自身分泌的化学引诱剂梯度运动。在这里，我们展示了这些复杂模式是如何形成的。远距离的空间秩序源于两个多细胞聚集体结构之间的相互作用：一个呈放射状扩展的“群体环”和移动性较低的心形聚集体。模式的形成是通过这两种分泌引诱剂（我们在此确定为天冬氨酸）来源的交替主导实现 的。模式几何形状会以一种系统的方式变化，这取决于聚集体保持活跃的时间长短；而这又反过来取决于底物（这里是琥珀酸） 的初始浓度。
