Collaborative Research: Structural and functional mechanisms of a molecular conveyor belt machinery that drives bacterial gliding motility

Several types of soil bacteria can actually glide across surfaces using specialized molecular machinery. This ability has evolved in multiple groups of microbes, and understanding how it works holds potential for advancing the bioeconomy, especially in agriculture. The research integrates work of specialists in genetics, biophysics, and in cryo-electron tomography (cryo-ET) to explore how multiple rotating motors on the bacterial surface coordinate to drive a protein-based conveyor belt on the bacterial cell surface, enabling cell movement analogous to a molecular snowmobile. By identifying the location , shape, and reactivity of the proteins involved, the project will uncover the fundamental structure and mechanical principles underlying bacterial gliding, providing insights for bio-inspired technological innovations and advances in soft material robotics. The investigators will also collaborate with the Arizona State 'Ask A Biologist' program to develop interactive online educational tools to enhance public understanding and student engagement in microbiology. This research specifically examines the molecular and mechanical intricacies of the bacterial gliding machinery, emphasizing its macromolecular assembly and torque-generation mechanism. Primary objectives include determining how multiple rotary motors cooperate to propel the conveyor belt and elucidating the distribution of tension across this belt. The project also aims to identify the polymerization mechanism of the conveyor belt and the molecular basis underlying its directional control. Employing a multidisciplinary approach, the research combines genetic manipulation to elucidate protein function, biophysical assays to characterize motor dynamics and conveyor belt properties, cryo-ET for high-resolution structural visualization in intact cells, and computational simulations to model molecular interactions and dynamics. Collectively, these methods will yield comprehensive insights into gliding motility at molecular and cellular scales, substantially advancing the understanding of biological nanomotors. This project is funded by the NSF/BIO/MCB Cell Dynamics & Function Program. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.