New weapons against persistent germs

This article was published in our newsletter. Sign up here.


Bacteria, fungi and viruses: billions of such tiny microorganisms live on and in our bodies, generally unnoticed. Some of them are entirely harmless, while other microorganisms can have unpleasant effects – and some can even pose a danger to us.

Some bacteria cause dangerous diseases

Clostridium difficile is one such bacterium: when present in large quantities in the gut, it produces toxins. Cells die off and people suffer from diarrhoea, which in some cases can prove fatal. This germ is particularly widespread in hospitals, where it poses a risk primarily to patients who are already weakened by disease. What makes Clostridium difficile so dangerous is the fact that most antibiotics cannot combat this bacteria as it is resistant.

Destructive mechanism decoded

Now that researchers in Hamburg have decoded the composition of this bacterium molecule by molecule, it is hoped that such intestinal infections could soon be treated – using viruses. What sounds incredible might really work, for the researchers at the European Molecular Biology Laboratory (EMBL) now know precisely how the bacterium switches from harmless standby mode into destruction mode. What is more, they have also found this same activation mechanism in viruses.

Viruses attack bacteria

They discovered the bacterium’s activation mechanism not in just any old viruses, however, but in bacteriophages. By their very nature, these microorganisms specialize in making bacteria harmless, and do so very effectively. They penetrate the cells and multiply there until the cell explodes.

Healing power of viruses experiences a revival

Researchers have been thinking about using bacteriophages to cure diseases for more than one hundred years. With the success of antibiotics in the second half of the twentieth century, however, science lost its interest in these microorganisms. The Hamburg researchers could now bring about their widespread revival, as the switching mechanism they have discovered is to be found in many different types of bacteriophage. And each is specialized in different bacteria. “This knowledge could allow us to engineer effective, specific bacteriophages, not just for Clostridium difficile infections, but for a wide range of pathogenic bacteria related to human health, agriculture and the food industry”, says Rob Meijers from EMBL. It is conceivable, in other words, that bacteriophages could actually be used as an alternative to antibiotics in future.

More information

European Molecular Biology Laboratory (EMBL) Hamburg website: