美国加州大学圣地亚哥分校Terence Hwa小组发现，趋化性可作为一种导航策略，以促进细菌向周围区域拓展。2019年11月6日，《自然》杂志在线发表了这项成果。
研究人员通过系统地观察大肠杆菌在软琼脂中的时空动态来确定趋化作用的替代作用。在养分充足的条件下，趋化作用会在当前环境中养分耗尽之前，促进细菌种群向无菌的区域扩展。在此过程中，低水平的化学引诱剂可充当类似香气的线索，从而确定方向并提高菌群沿着自生引诱剂梯度的移动速度。这种导航范围扩展的过程比遵循规范的Fisher-Kolmogorov动力定位非引导扩展更快地传播，并带来更大的数量增长，因此是在空间足够、营养丰富的环境中促进群体增长的通用策略。
据了解，细菌趋化性，即细胞沿趋化剂梯度的定向运动，是分子生物学中最典型的特征之一，但对其生理学角色知之甚少。当营养耗尽时，这通常被视为饥饿反应，或者是有害情况下的逃逸反应。
附：英文原文
Title: Chemotaxis as a navigation strategy to boost range expansion
Author: Jonas Cremer, Tomoya Honda, Ying Tang, Jerome Wong-Ng, Massimo Vergassola, Terence Hwa
Issue&Volume: 2019-11-06
Abstract: Bacterial chemotaxis, the directed movement of cells along gradients of chemoattractants, is among the best-characterized subjects in molecular biology110, but much less is known about its physiological roles11. It is commonly seen as a starvation response when nutrients run out, or as an escape response from harmful situations1216. Here we identify an alternative role of chemotaxis by systematically examining the spatiotemporal dynamics of Escherichia coli in soft agar12,17,18. 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 FisherKolmogorov dynamics19,20 and is therefore a general strategy to promote population growth in spatially extended, nutrient-replete environments. Pioneering bacterial cells use chemotaxis along self-generated attractant gradients to facilitate rapid colonization of nutrient-replete environments.
DOI: 10.1038/s41586-019-1733-y
Source:https://www.nature.com/articles/s41586-019-1733-y
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html
本期文章：《自然》：Online/在线发表
