Scientists have discovered a strange new feature of a protein that is thought to be important in the development of tuberculosis.
The protein contains a “huge” interior pocket, the likes of which has never before been seen. It appears capable of passing a wide range of other molecules into the bacterial cell.
Cornelius Gati, a structural biologist who worked on the study, said they discovered the pocket while investigating the role this “transporter protein” on the surface of tuberculosis bacteria plays in sucking up vitamin B12 from surrounding cells.
It was widely thought that transporter proteins that import molecules into cells tend to be quite specialised, with structures that are tailored to grab onto particular molecules and move them into cells.
This one, Gati found, was a generalist that could, in principle, bring in small nutrients, larger molecules like vitamin B12, or even some antibiotics.
In theory, the new findings could lead to new ways to treat tuberculosis, but for the moment Gati and colleagues are trying to get a better handle on what the protein can and cannot transport.
“We’ve never seen anything like this before,” Gati said. “It doesn’t really make sense.”
