Chemotaxis as a navigation strategy to boost range expansion
Chemotaxis as a navigation strategy to boost range expansion
复制标题
DOI：
10.1038/s41586-019-1733-y
复制
发表时间：
2019-11-28
期刊：
影响因子：
64.8
通讯作者：
Hwa, Terence
中科院分区：
文献类型：
--
作者：
Cremer, Jonas;Honda, Tomoya;Hwa, Terence
细菌的趋化性，即细胞沿趋化剂的梯度沿着定向运动，是分子生物学中最具特征的主题之一（1-10），但对其生理作用知之甚少（11）。它通常被视为营养素耗尽时的饥饿反应，或作为有害情况下的逃避反应（12-16）。在这里，我们通过系统地研究软琼脂中大肠杆菌的时空动力学，确定了趋化性的另一种作用（12，17，18）。在营养物充足的条件下，趋化性促进细菌种群在当前环境中营养物耗尽之前向未占领的领土扩张。低水平的化学引诱物在这个过程中作为芳香样线索，建立方向，并提高人口运动的速度沿着自生引诱梯度。这种导航范围扩张的过程比遵循规范的Fisher-Kolmogorov动力学（19，20）的无引导扩张传播得更快，产生更大的种群增益，因此是在空间扩展，营养丰富的环境中促进种群增长的一般策略。
Bacterial chemotaxis, the directed movement of cells along gradients of chemoattractants, is among the best-characterized subjects in molecular biology(1-10), but much less is known about its physiological roles(11). It is commonly seen as a starvation response when nutrients run out, or as an escape response from harmful situations(12-16). Here we identify an alternative role of chemotaxis by systematically examining the spatiotemporal dynamics of Escherichia coli in soft agar(12,17,18). Chemotaxis in nutrient-replete conditions promotes the expansion of bacterial populations into unoccupied territories well before nutrients run out in the current environment. Low levels of chemoattractants act as aroma-like cues in this process, establishing the direction and enhancing the speed of population movement along the self-generated attractant gradients. This process of navigated range expansion spreads faster and yields larger population gains than unguided expansion following the canonical Fisher-Kolmogorov dynamics(19,20) and is therefore a general strategy to promote population growth in spatially extended, nutrient-replete environments.