FOF1-ATPase Motor-Embedded Chromatophore as Drug Delivery System: Extraction, Cargo Loading Ability and Mucus Penetration Ability

FOF1-ATPase Biomolecular Motor: Structure, Motility Manipulations, and Biomedical Applications

Biomolecular motors are dynamic systems found in organisms with high energy conversion efficiency. FOF1-ATPase is a rotary biomolecular motor known for its near 100% energy conversion efficiency. It utilizes the synthesis and hydrolysis of ATP to induce conformational changes in motor proteins, thereby converting chemical energy into mechanical motion. Given their high efficiency, autonomous propulsion capability, and modifiable structures, FOF1-ATPase motors have attracted significant attention for potential biomedical applications. This Review aims to introduce the detailed structure of FOF1-ATPase, explore various motility manipulation strategies, and summarize its applications in biological detection and cargo delivery. Additionally, innovative research methods are proposed to analyze the motion mechanism of FOF1-ATPase more comprehensively, with the goal of advancing its biomedical applications. Finally, this Review concludes with key insights and future perspectives.

An FOF1-ATPase motor-embedded chromatophore as a nanorobot for overcoming biological barriers and targeting acidic tumor sites

Despite the booming progress of anticancer nanomedicines in the past two decades, precise tumor-targetability and sufficient tumor-accumulation are less successful and still require further research. To tackle this challenge, herein we present a biomolecular motor (FOF1-ATPase)-embedded chromatophore as nanorobot to efficiently overcome biological barriers, and thoroughly investigate its chemotactic motility, tumor-accumulation ability and endocytosis. Chromatophores embedded with FOF1-ATPase motors were firstly extracted from Thermus thermophilus, then their properties were fully characterized. Specifically, two microfluidic platforms (laminar flow microchip and tumor microenvironment (TME) microchip) were designed and developed to fully investigate the motility, tumor-accumulation ability and endocytosis of the chromatophore nanorobot (CN). The results from the laminar flow microchip indicated that the obtained CN possessed the strongly positive chemotaxis towards protons. And the TME microchip experiments verified that the CN had a desirable tumor-accumulation ability. Cellular uptake experiments demonstrated that the CN efficiently promoted the endocytosis of the fluorescence DiO into the HT-29 cells. And the in vivo studies revealed that the intravenously administered CN exhibited vigorous tumor-targetability and accumulation ability as well as highly efficient antitumor efficacy. All the results suggested that FOF1-ATPase motors-embedded CN could be promising nanomachines with powerful self-propulsion for overcoming physiological barriers and tumor-targeted drug delivery. STATEMENT OF SIGNIFICANCE: In this study, we demonstrated that FOF1-ATPase-embedded chromatophore nanorobots exhibit a strong proton chemotaxis, which not only plays a key role in tumor-targetability and accumulation, but also promotes tumor tissue penetration and internalization. The results of in vitro and in vivo studies indicated that drug-loaded chromatophore nanorobots are capable to simultaneously accomplish tumor-targeting, accumulation, penetration and internalization for enhanced tumor therapy. Our study provides a fundamental basis for further study on FOF1-ATPase-embedded chromatophore as tumor-targeting drug delivery systems that have promising clinical applications. It offers a new and more efficient delivery vehicle for cancer related therapeutics.