Tekel Stefan J, Smith Christina L, Lopez Brianna, Mani Amber, Connot Christopher, Livingstone Xylaan, Haynes Karmella A
School of Biological and Health Systems Engineering, Arizona State University, Tempe, AZ, United States.
School of Life Sciences, Arizona State University, Tempe, AZ, United States.
Front Bioeng Biotechnol. 2019 Apr 17;7:80. doi: 10.3389/fbioe.2019.00080. eCollection 2019.
Gene regulators that are controlled by membrane-permeable compounds called homoserine lactones (HSLs) have become popular tools for building synthetic gene networks that coordinate behaviors across populations of engineered bacteria. Synthetic HSL-signaling systems are derived from natural DNA and protein elements from microbial quorum signaling pathways. Crosstalk, where a single HSL can activate multiple regulators, can lead to faults in networks composed of parallel signaling pathways. Here, we report an investigation of quorum sensing components to identify synthetic pathways that exhibit little to no crosstalk in liquid and solid cultures. In previous work, we characterized the response of a single regulator (LuxR) to 10 distinct HSL-synthase enzymes. Our current study determined the responses of five different regulators (LuxR, LasR, TraR, BjaR, and AubR) to the same set of synthases. We identified two sets of orthogonal synthase-regulator pairs (BjaI/BjaR + EsaI/TraR and LasI/LasR + EsaI/TraR) that show little to no crosstalk when they are expressed in BL21. These results expand the toolbox of characterized components for engineering microbial communities.
由被称为高丝氨酸内酯（HSLs）的膜通透性化合物控制的基因调控因子，已成为构建合成基因网络的常用工具，这些网络可协调工程细菌群体的行为。合成HSL信号系统源自微生物群体感应信号通路中的天然DNA和蛋白质元件。串扰（即单个HSL可激活多个调控因子的情况）会导致由平行信号通路组成的网络出现故障。在此，我们报告了一项对群体感应组件的研究，以识别在液体和固体培养物中几乎没有串扰的合成通路。在之前的工作中，我们表征了单个调控因子（LuxR）对10种不同HSL合成酶的反应。我们目前的研究确定了五种不同调控因子（LuxR、LasR、TraR、BjaR和AubR）对同一组合成酶的反应。我们鉴定出两组正交的合成酶 - 调控因子对（BjaI/BjaR + EsaI/TraR和LasI/LasR + EsaI/TraR），当它们在BL21中表达时，几乎没有串扰。这些结果扩展了用于工程化微生物群落的已表征组件的工具箱。
