Cell-free protein synthesis (CFPS) is a rapidly maturing in vitro gene expression platform that can be used to transcribe and translate nucleic acids at the point of need, enabling on-demand synthesis of peptide-based vaccines and biotherapeutics as well as the development of diagnostic tests for environmental contaminants and infectious agents. Unlike traditional cell-based systems, CFPS platforms do not require the maintenance of living cells and can be deployed with minimal equipment; therefore, they hold promise for applications in low-resource contexts, including spaceflight. Here, we evaluate the performance of the cell-free platform BioBits aboard the International Space Station by expressing RNA-based aptamers and fluorescent proteins that can serve as biological indicators. We validate two classes of biological sensors that detect either the small-molecule DFHBI or a specific RNA sequence. Upon detection of their respective analytes, both biological sensors produce fluorescent readouts that are visually confirmed using a hand-held fluorescence viewer and imaged for quantitative analysis. Our findings provide insights into the kinetics of cell-free transcription and translation in a microgravity environment and reveal that both biosensors perform robustly in space. Our findings lay the groundwork for portable, low-cost applications ranging from point-of-care health monitoring to on-demand detection of environmental hazards in low-resource communities both on Earth and beyond.

中文翻译：

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国际空间站上无细胞蛋白质合成的验证

无细胞蛋白质合成（CFPS）是一种快速成熟的体外基因表达平台，可用于在需要时转录和翻译核酸，从而实现基于肽的疫苗和生物治疗药物的按需合成以及开发环境污染物和传染源的诊断测试。与传统的基于细胞的系统不同，CFPS平台不需要维护活细胞，并且可以用最少的设备进行部署；因此，它们有望在资源匮乏的环境中得到应用，包括航天。在这里，我们通过表达可作为生物指示剂的基于 RNA 的适体和荧光蛋白来评估国际空间站上无细胞平台 BioBits 的性能。我们验证了两类生物传感器，它们可以检测小分子 DFHBI 或特定的 RNA 序列。在检测到各自的分析物后，两个生物传感器都会产生荧光读数，使用手持式荧光观察器进行视觉确认并成像以进行定量分析。我们的研究结果提供了对微重力环境中无细胞转录和翻译动力学的见解，并揭示了两种生物传感器在太空中表现强劲。我们的研究结果为便携式、低成本应用奠定了基础，这些应用包括从现场护理健康监测到地球及其他地区资源匮乏社区的环境危害的按需检测。