Many meteorites hit the earth crust every year without barely any consequence to humankind. Yet have you ever wondered if there will be a time when these comets or asteroids – travelling at 24 to 100 miles a second and composed of solid debris – would be large enough to cause massive devastation to the planet? Well, according to scientists, the chances are that our species may be blown away first by enemies invisible to the human naked eye: Bacteria! Of course, you will protest and say “these bugs are essential in the maintenance of life due to their work on nitrogen fixation (nitrogen availability to plants is crucial to their growth) or breaking down molecules in our intestines so we can assimilate them. Thus, they are indispensable in the life-cycle!” You are absolutely right. But some bacteria can be devilish little beasts that can kill us in a matter of days and are fast becoming immune to our weapons: these are called “super bacteria.”Still not concerned? Then keep reading...

Super bacteria are a major public health concern throughout the world as a result of misuse and overuse of medication. These are germs that are resistant to most antibiotics. Such microorganisms have adapted to common antibiotics, for example, and have gotten more and more resistant via genetic mutations. In some cases, they are even developing resistance against the antibiotics of last resort. The outcome is horrifying since the infected patient dies, and the resistant bacteria continue to spread quietly among us. Cancer treatment and surgeries are under threat without effective antibiotics... Frightening! Now let me introduce you to one of the stars of this horror movie and focus of my PhD: Klebsiella pneumoniae.

K. pneumoniae causes hospital-acquired infections such as pneumonia, bloodstream infections, infections in newborns and patients in the intensive- care unit. The antibiotic colistin is kept as a treatment of last resort when all else fails. However, resistance to this molecule was already observed in several countries, which makes these bacteria pretty much untreatable in some cases. In my PhD I try to understand its resistance mechanisms via gene expressions related to the synthesis of the lipopolysaccharide forming the external wall of K. pneumoniae. This molecule is actually the action target of colistin. Additionally, I research alternative therapeutic ways to treat the infection before a successful new antibiotic comes into the market.

The clock is ticking against a cruel attack of invisible assassins. Scientists pursue their research on finding new antimicrobial molecules that eventually will give us some more time on earth... unless there is a meteorite in between.

I am Marine Herold-Manuelli, a hospital pharmacist and a PhD student who truly believe that pharmacists should be active actors in the fight against bacterial resistance.

Text by Fernanda Haffner

Illustration by Luis Rubio