elegans, the team found bacteria species linked to the development of the conditions, and others that can counteract the effect.

Researchers have identified gut bacteria species that appear to play a role in the development of neurodegenerative diseases such as Alzheimer’s, Parkinson’s and motor neurone disease.

Previous research has shown a link between the conditions and changes in the gut microbiome, but among the thousands of species that live there, it wasn’t easy to identify which ones have an effect.

Now, a team based at the University of Florida, USA, have not only identified the harmful bacteria, but have also shown that certain other bacteria species can produce compounds that counteract the effect.

In this study, we were able to show that specific species of bacteria play a role in the development of these conditions,” said Dr Daniel Czyz, assistant professor at the University of Florida.

“We also showed that some other bacteria produce compounds that counteract these ‘bad’ bacteria.

Recent studies have shown that patients with Parkinson’s and Alzheimer’s disease are deficient in these ‘good’ bacteria, so our findings may help explain that connection and open up an area of future study,” he said.

The team studied the link between gut bacteria and neurodegenerative disease in a worm called C.

“We saw that worms colonised by certain bacteria species were lit up with aggregates that were toxic to tissues, while those colonised by the control bacteria were not.”.

Online assistant, BBC Science Focus.

Sara is the online assistant at BBC Science Focus