Nagoya University’s collaborative research has shed light on the FliG molecule in bacterial flagellar motors, revealing significant potential for the development of advanced, controllable nanomachines. This breakthrough could have far-reaching impacts in the realms of medical technology and the creation of artificial life.
The research team delved into the mechanisms of bacterial movement, focusing on the FliG molecule located in the flagellar layer, the bacteria’s propulsion system. These insights pave the way for future creation of nanomachines with precise movement control.
This study, led by Professor Emeritus Michio Homma and Professor Seiji Kojima from Nagoya University’s Graduate School of Science, in collaboration with Osaka University and the Nagahama Institute of Bio-Science and Technology, has been published in the journal iScience.
Nanomachines Inspired by Flagellar Motors
The miniaturization of nanomachines has led researchers to seek inspiration from microscopic organisms for motion and operation techniques. The bacterial flagellar motor, capable of rotating at 20,000 rpm in both directions, offers a model for high-efficiency, high-speed movement in nanomachines. This biological motor’s efficiency and agility, if replicated, could greatly enhance nanomachine maneuverability and efficiency.
Understanding How Bacteria Move
Bacterial flagellar motors consist of a rotor and a stationary part, the stator, analogous to a car’s engine. The rotor’s movement, controlled by the stator, propels the bacteria forward or backward. The C ring, a protein complex, governs this motion, with the FliG molecule acting as a clutch, facilitating directional changes. The study also investigated mutations in FliG, particularly the G215A mutation, which causes unidirectional rotation.
The Significance of FliG and Water Molecules
The research revealed that the G215A mutation in Vibrio alginolyticus results in continuous clockwise rotation due to changes in FliG and the surrounding water molecules. These findings highlight the differences in FliG structure and water molecule interactions during various rotational directions.
Professor Homma emphasized the importance of these discoveries in understanding the molecular mechanisms behind motor rotation direction changes. He stated, “This significant breakthrough in understanding the FliG protein’s physical properties opens new avenues for designing highly efficient, compact motors.” He envisages these advancements being applied in medicine and artificial life design.
The study, titled “Changes in the hydrophobic network of the FliGMC domain induce rotational switching of the flagellar motor,” by Tatsuro Nishikino, Atsushi Hijikata, Seiji Kojima, Tsuyoshi Shirai, Masatsune Kainosho, Michio Homma, and Yohei Miyanoiri, was published on 11 July 2023 in iScience.
DOI: 10.1016/j.isci.2023.107320
