Bacteria use a tiny rotary motor to swim and sense their chemical surroundings—researchers now want to wire that motor directly into a microchip. The bacterial flagellar motor is one of the fastest and most sensitive biological sensors known, detecting specific chemicals at nanomolar concentrations within seconds. But reading its rotation currently requires bulky optical microscopes, one bacterium at a time. This project aims to replace that with an electrical readout by anchoring individual bacteria onto a chip and testing two detection methods: an integrated circuit and a graphene surface. If successful, the approach would turn each motor into a portable, high-throughput biosensor that simultaneously measures three things—the cell’s own physiology, mechanical forces, and specific chemicals. This is fundamental science. The immediate goal is to prove that electrical detection works at the required resolution. If it does, the result could be a biosensor-on-a-chip that is small, fast, and cheap enough for field use—detecting pathogens in water, monitoring industrial fermentation, or measuring ion gradients in real time. Past fundamental work on bacterial motors has already deepened understanding of chemotaxis and mechanosensing; this project extends that into a practical device architecture.
View original technical description
The Bacterial Flagellar Motor is one of nature's rare rotary molecular machines. It enables bacterial swimming and is a key part of the bacterial chemotactic network that enables bacteria to direct their movement given the chemical environment. This network is one of the best-studied chemical signalling networks in biology, sensing down to nanomolar concentrations of specific chemicals on the time scale of seconds. The motor's rotational speed is linearly proportional to the bacterial electrochemical gradients, most notably of proton or sodium ions, while its direction is regulated by the chemotactic network. Recently, it has been discovered that the motor is also a mechanosensor. Given these properties, the motor has the potential to serve as a multimodal biosensor with unprecedented speed and sensitivity, and thus a tool for characterizing and studying the external environment, but also bacterial physiology itself. However, at the resolution needed, motor speed and rotational direction are currently detected optically, one motor at a time. A step-change in harnessing the unprecedented potential of this rotary molecular machine would be to detect each motor's rotation electrically and with high throughput. Here I propose to achieve this by specifically attaching individual bacteria to a precise location on the surface and testing two electrical means of detecting the motor's rotation: an integrated circuit and a graphene surface. The detection method will also be employed to fully characterize the three different sensing modalities offered by the flagellar motor: that of cells own physiology, of mechanical forces and of a given set of chemicals. The success of the project we will enable portable biosensor-on-a-chip configuration of the motor speed and rotational direction detection, which can be a game-changer in the biosensing field.
Plain English summaries and category classifications on this site are generated by AI and may not perfectly reflect the original research.
Is something wrong? Let us know