In bacteria-driven microswimmers, i.e., bacteriabots, artificial cargos are attached to flagellated chemotactic bacteria for active delivery with potential applications in biomedical technology. Controlling when and where bacteria bind and release their cargo is a critical step for bacteriabot fabrication and efficient cargo delivery/deposition at the target site. Toward this goal, photoregulating the cargo integration and release in bacteriabots using red and far-red light, which are noninvasive stimuli with good tissue penetration and provide high spatiotemporal control, is proposed. In the bacteriabot design, the surfaces of E. coli and microsized model cargo particles with the proteins PhyB and PIF6, which bind to each other under red light and dissociate from each other under far-red light are functionalized. Consequently, the engineered bacteria adhere and transport the model cargo under red light and release it on-demand upon far-red light illumination due to the photoswitchable PhyB-PIF6 protein interaction. Overall, the proof-of-concept for red/far-red light switchable bacteriabots, which opens new possibilities in the photoregulation in biohybrid systems for bioengineering, targeted drug delivery, and lab-on-a-chip devices, is demonstrated.

中文翻译：

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细菌驱动的微游泳器中的红/远红灯可切换的货物附件和释放。

在细菌驱动的微游泳器中，即在细菌机器人中，将人造货物附着在鞭毛化趋化细菌上，以进行主动传递，并在生物医学技术中具有潜在的应用。控制细菌在何时何地结合并释放其货物是细菌机器人制造和在目标位置进行有效货物运输/沉积的关键步骤。为了实现这一目标，提出了使用红色和远红外光对细菌机器人中货物的整合和释放进行光调节的方法，这是具有良好组织渗透性并提供高时空控制的非侵入性刺激。在细菌机器人的设计中，功能化的是带有蛋白质PhyB和PIF6的大肠杆菌和带有蛋白质PhyB和PIF6的超小型模型货物颗粒的表面，这些表面在远红外光下彼此分离。所以，由于光交换的PhyB-PIF6蛋白相互作用，工程细菌会在红光下粘附并运输模型货物，并在远红光照明下按需释放。总体而言，演示了用于红/远红光可切换细菌机器人的概念验证，这为生物工程，目标药物递送和芯片实验室设备的生物混合系统中的光调节开辟了新的可能性。