Although there are many bacteria that benefit us, bacteria can be hidden creatures, some of which use micro”-injected toxins into host cells. Now researchers at the Max Planck Institute have found a way to have a beneficial effect on people by swapping these toxins for other chemicals, such as drugs.
Many bacteria infect host cells through this “syringe” mechanism, including E. coli and Yersinia. These bacteria “lock” on the cells and then push the passage sway over its protective membrane. From there, bacteria pass toxic proteins to the cell’s fragile center, which usually kills it within minutes.
Max Planck’s researchers have previously studied the process using cryogenic electron microscopes. This involves cooling the sample to a low temperature and then examining it with a powerful electron microscope. This allows scientists to observe the structure of these proteins from three dimensions and at high resolution.
For the new study, the team analyzed whether they could replace these toxic protein payloads with more beneficial substances. To be sure, as long as three conditions are met, they can. First, the protein must have a certain size – it must be greater than 20kDa to remain stable. Second, they must be positively charged. Third, they cannot interact with the molecules that form “capsules” that hold payloads.
Stefan Raunser, lead researcher on the study, said: “With this technology, we are taking the first step towards the ultimate goal of using these nano-injectors to target the introduction of drugs into human cells. “
Although the process can be adapted to deliver good drugs to cells, in some cases toxic proteins can be easily injected. The team says nano”ssyringes can be designed to “sniff out” cancer cells and lock them in and deliver poisons without damaging healthy cells. But in order for it to work, more research is needed to determine how molecules are connected to the cell surface.
“We are currently looking for a ‘stop’ for toxins, ” says Raunser. “Once we find them and understand how toxins bind to the cell surface, our goal is to specifically alter the injection mechanism so that it can identify cancer cells. We can then inject the killer protein specifically into the tumor cells. This will create new possibilities for the smallest side effects of cancer drugs. “
The study was published in the journal Nature Communications.