Department of Biomedical Engineering, University of Connecticut, Storrs, Connecticut 06269, United States.
Department of Molecular and Cellular Biology, University of Connecticut, Storrs, Connecticut 06269, United States.
ACS Synth Biol. 2021 Feb 19;10(2):345-356. doi: 10.1021/acssynbio.0c00498. Epub 2021 Jan 19.
Microorganisms play a vital role in shaping the soil environment and enhancing plant growth by interacting with plant root systems. Because of the vast diversity of cell types involved, combined with dynamic and spatial heterogeneity, identifying the causal contribution of a defined factor, such as a microbial exopolysaccharide (EPS), remains elusive. Synthetic approaches that enable orthogonal control of microbial pathways are a promising means to dissect such complexity. Here we report the implementation of a synthetic, light-activated, transcriptional control platform using the blue-light responsive DNA binding protein EL222 in the nitrogen fixing soil bacterium . By fine-tuning the system, we successfully achieved optical control of an EPS production pathway without significant basal expression under noninducing (dark) conditions. Optical control of EPS recapitulated important behaviors such as a mucoid plate phenotype and formation of structured biofilms, enabling spatial control of biofilm structures in . The successful implementation of optically controlled gene expression in enables systematic investigation of how genotype and microenvironmental factors together shape phenotype .
微生物通过与植物根系相互作用，在塑造土壤环境和促进植物生长方面发挥着至关重要的作用。由于涉及的细胞类型非常多样，再加上动态和空间异质性，要确定一个特定因素（如微生物胞外多糖 (EPS)）的因果贡献仍然具有挑战性。能够对微生物途径进行正交控制的合成方法是剖析这种复杂性的一种有前途的手段。在这里，我们报告了在固氮土壤细菌中使用蓝光响应 DNA 结合蛋白 EL222 实施合成、光激活转录控制平台的情况。通过对该系统进行精细调整，我们成功地实现了 EPS 生产途径的光学控制，在非诱导（黑暗）条件下没有明显的基础表达。EPS 的光学控制再现了重要行为，如粘液平板表型和结构化生物膜的形成，从而能够在 中对生物膜结构进行空间控制。在 中成功实施光控基因表达使系统研究基因型和微环境因素如何共同塑造表型成为可能。
