Unité de Recherche en Biologie des Micro-organismes, University of Namur, 61 Rue de Bruxelles, 5000 Namur, Belgium.
Unité de Recherche en Biologie Végétale, University of Namur, 61 Rue de Bruxelles, 5000 Namur, Belgium.
Nat Microbiol. 2016 Jul 4;1(9):16098. doi: 10.1038/nmicrobiol.2016.98.
Stress response to fluctuating environments often implies a time-consuming reprogramming of gene expression. In bacteria, the so-called bet hedging strategy, which promotes phenotypic stochasticity within a cell population, is the only fast stress response described so far(1). Here, we show that Caulobacter crescentus asymmetrical cell division allows an immediate bimodal response to a toxic metals-rich environment by allocating specific defence strategies to morphologically and functionally distinct siblings. In this context, a motile swarmer cell favours negative chemotaxis to flee from a copper source, whereas a sessile stalked sibling engages a ready-to-use PcoAB copper homeostasis system, providing evidence of a prompt stress response through intrinsic bacterial dimorphism.
应对不断变化的环境的应激反应通常意味着对基因表达进行耗时的重新编程。在细菌中，迄今为止描述的唯一快速应激反应是所谓的“赌注对冲”策略，该策略促进细胞群体内的表型随机性(1)。在这里，我们表明，新月形柄杆菌的不对称细胞分裂通过将特定的防御策略分配给形态和功能上不同的子细胞，从而对富含有毒金属的环境做出即时的双峰反应。在这种情况下，一个游动的 swarmer 细胞有利于负趋化性以逃离铜源，而一个静止的 stalked 子细胞则利用现成的 PcoAB 铜稳态系统，通过内在的细菌二态性提供了快速应激反应的证据。
