Liu Feng, Mao Junwen, Lu Ting, Hua Qiang
State Key Laboratory of Bioreactor Engineering , East China University of Science and Technology , Shanghai 200237 , China.
Department of Bioengineering , University of Illinois at Urbana-Champaign , Urbana , Illinois 61801 , United States.
ACS Synth Biol. 2019 Aug 16;8(8):1713-1722. doi: 10.1021/acssynbio.9b00110. Epub 2019 Aug 8.
Synthetic microbial consortia are a rapidly growing area of synthetic biology. So far, most consortia are designed without considering their environments; however, in nature, microbial interactions are constantly modulated by cellular contexts, which, in principle, can dramatically alter community behaviors. Here we present the construction, validation, and characterization of an engineered bacterial predator-prey consortium that involves a chloramphenicol (CM)-mediated, context-dependent cellular interaction. We show that varying the CM level in the environment can induce success in the ecosystem with distinct patterns from predator dominance to prey-predator crossover to ecosystem collapse. A mathematical model successfully captures the essential dynamics of the experimentally observed patterns. We also illustrate that such a dependence enriches community dynamics under different initial conditions and further test the resistance of the consortium to invasion with engineered bacterial strains. This work exemplifies the role of the context dependence of microbial interactions in modulating ecosystem dynamics, underscoring the importance of including contexts into the design of engineered ecosystems for synthetic biology applications.
合成微生物群落是合成生物学中一个快速发展的领域。到目前为止，大多数群落的设计并未考虑其所处环境；然而，在自然界中，微生物间的相互作用不断受到细胞环境的调节，原则上，这会极大地改变群落行为。在此，我们展示了一个经过工程改造的细菌捕食者 - 猎物群落的构建、验证及特性描述，该群落涉及氯霉素（CM）介导的、依赖环境的细胞间相互作用。我们表明，改变环境中CM的水平可在生态系统中诱导出不同模式的成功，从捕食者主导到猎物 - 捕食者交叉再到生态系统崩溃。一个数学模型成功捕捉到了实验观察到的模式的基本动态。我们还证明，这种依赖性在不同初始条件下丰富了群落动态，并进一步测试了该群落对工程细菌菌株入侵的抗性。这项工作例证了微生物相互作用的环境依赖性在调节生态系统动态中的作用，强调了在合成生物学应用的工程生态系统设计中纳入环境因素的重要性。
