In theory, building a nanodevice is not completely different from building other equipment. The engineer first designs the necessary components and then decides how to assemble them to achieve the desired function. However, the biggest difficulty in building nanodevices is that they must be effectively designed at this scale. Fortunately, evolution has successfully solved countless engineering challenges, and scientists can always find inspirational natural designs in the world of proteins.
Researchers at the University of Gothenburg and the BiOMaDe Technology Center in the Netherlands demonstrated the power of this approach. Ben Feringa explained that MscL is a membrane protein on E. coli. It is a conduit that controls the movement of substances into and out of the cell. It can be reversed or turned off under the action of light. In a natural system, this is a kind of safety. valve. He said: "It can prevent cells from bursting. If the pressure inside the cell is too large, the pores of the channel will open 3 nanometers, and many things will flow out. Therefore, it is a very good channel and can automatically open. The open, ideal state can control its opening and closing."
Normally, MscL is always tight due to hydrophobic interactions. However, if there is a considerable load, the MscL's small hole will be forced to open until the load disappears. Feringa and colleagues designed a reversible optical switch that charges under ultraviolet light and discharges under visible light. This switch is attached to a specific part of the MscL monomer and the engineered protein is sent to the synthetic membrane. The experiment confirmed that the ultraviolet light can induce the opening of the channel until it is re-closed under the action of visible light. In the second round of experiments, the researchers injected the modified MscL into the microliposomes, which contained fluorescent dyes. Experiments showed that in addition to a small amount of leakage, light can effectively regulate the fluorescent dye in the liposome. Release.
This is just an initial discovery, and researchers are improving this approach, and they hope that this technology can be applied to controlled drug delivery. Feringa has far greater goals, and he foresaw the enormous capabilities of these tiny devices and believe they can be the basic building blocks of precision nanodevices. He said: "In the field of nanotechnology, we rarely know how to integrate parts, how to assemble them and let them work properly." "When the basic principles are proven, the new challenge is to see how to make this nano valve and part The nanofluidic channels combine to perform the function of the valve."
Light-controlled protein channels may represent a new generation of nanotechnology tools.