RNA-based fluorescent (RBF) biosensors have been applied to detect a variety of metabolites in vitro and in live cells. They are designed by combining the ligand sensing domain of natural riboswitches with in vitro selected fluorogenic aptamers. Different biosensor topologies have been developed to accommodate the diversity of riboswitch structures. Here we show that circular permutation of the riboswitch ligand sensing domain also gives functional biosensors, using the SAM-I riboswitch as our model. We reveal that this design can enhance fluorescence turn-on and ligand binding affinity compared to the non-permuted topology.

中文翻译：

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使用核糖开关的圆形排列设计荧光生物传感器

基于 RNA 的荧光 (RBF) 生物传感器已被用于检测体外和活细胞中的各种代谢物。它们是通过将天然核糖开关的配体感应域与体外选择的荧光适体相结合而设计的。已经开发了不同的生物传感器拓扑以适应核糖开关结构的多样性。在这里，我们展示了核糖开关配体传感域的循环排列也提供了功能性生物传感器，使用 SAM-1 核糖开关作为我们的模型。我们发现，与非置换拓扑结构相比，这种设计可以增强荧光开启和配体结合亲和力。