“Discovery of new type of antibiotic”

“Researchers from Radboud university medical center and Radboud University presented their initial results this week in Cell Chemical Biology.

Our bodies harbor millions of bacteria. Usually this is not a problem; in fact, we need many of these bacteria to survive. However, sometimes the balance shifts and these previously innocent bacteria can suddenly make us sick. Non-typeable Haemophilus influenzae is one of these bacteria. In children, it can cause middle ear infection, a condition that affects 65 to 300 million people worldwide. It is a major cause of hearing loss. The bacterium is also found in the vast majority of patients with acute exacerbation of COPD, which leads to three million deaths worldwide every year.

Invisibility cloak

To cause disease, the bacterium needs sialic acid, a sugar that is abundantly available in our bodies. The bacterium does not contain these sugars, so it takes them from us. After absorbing the sialic acid, the bacterium incorporates the sugar into its cell wall. As a result, the bacterium makes itself “invisible” to the immune system, which can no longer recognize the bacterium and therefore leaves it alone.

This “invisibility cloak” prompted researcher Jeroen Langereis, theme Infectious diseases and global health, and his colleagues at Radboud university medical center and Radboud University to determine whether they could prevent the incorporation of sialic acid into the bacterial wall. They experimented with individual cells and their intervention worked. “The drug we designed for this experiment is a new type of antibiotic,” explains Langereis. The bacterium actively absorbs sialic acid via a transporter. The new antibiotic agent enters the bacterial cell via the same transporter. The human body produces sialic acid, but its cells do not have a sialic acid transporter. Therefore, the new drug is probably not harmful to our own cells.”