Scientists discover new molecule that combats viral infection in bacteria

Research news

A collaboration between researchers at the University of Jyväskylä and the University of St Andrews has unveiled a new molecule in microbes that acts as a 'distress signal' when viruses are detected. The discovery paves the way to a new class of bioactive molecules that could lead to drugs with applications in human health and antimicrobial therapy.

Researcher Ville Hoikkala from the University of Jyvaskyla carried out the bioinformatic analyses.

The research group led by Malcolm White from the School of Biology at University of St Andrews, discovered new molecule SAM-AMP, previously unknown to science, which is made by joining two of the most widespread chemicals present in all living things, SAM and ATP, in a completely new way.

- SAM-AMP is produced by a bacterium that is being infected by a virus. It is a signal molecule that activates a lethal component in the cell, setting the cell on suicide mode. While this leads to the death of the cell, this "altruistic suicide" can be beneficial to the bacterial population. Similar mechanisms are found also in human cells, says researcher Ville Hoikkala from the University of Jyvaskyla. He carried out the bioinformatic analyses in a collaboration between the University of Jyväskylä and the University of St Andrews.

Biotechnological potential

An extensive bioinformatic analysis across tens of thousands of microbial genomes revealed that the molecular machinery required to produce this new molecule is present in a wide range of microbes.

- The fact that this molecule is likely to be produced across such a wide range of microbial species suggests it is an effective signal in bacterial anti-virus operations. In the future, it will be exciting to see what kind of countermeasures viruses have developed to overcome these defenses, says Hoikkala.

As viruses are constantly infecting bacteria, SAM-AMP is being made in all of us, every day.

- It will be fascinating to explore how it affects bacteria and whether our own cells can sense this distress signal too. Now that we know how to make this molecule, we can manipulate the component parts to generate a whole family of novel compounds with potential applications in biomedicine, tells professor Malcolm White from the University of St Andrews.

The work is published in the leading academic journal Nature on 18.10.2023.

The article information:

• Antiviral type III CRISPR signalling via conjugation of ATP and SAM, Haotian Chi, Ville Hoikkala, Sabine Grüschow, Shirley Graham, Sally Shirran & Malcolm F. White, Nature (2023)
• Doi: https://doi.org/10.1038/s41586-023-06620-5
• Link to article: https://www.nature.com/articles/s41586-023-06620-5

Further information:

• Researcher Ville Hoikkala, [email protected]