University of Dundee

Bacteria weapon found to attack fungi as well as fellow bacteria

23 Jul 2018

New collaborative research from the Division of Molecular Microbiology in the School has discovered that a bacterial weapon commonly used by bacteria to kill each other also attacks fungal cells. The work by Dr Sarah Coulthurst, Professor Matthias Trost in Newcastle and colleagues has been published in Nature Microbiology.

Many bacteria use a weapon called the Type VI secretion system to fire toxic ‘effector’ proteins into neighbouring cells. This system is well known to be used by bacteria to kill other, rival bacterial cells as a means of competing against them. In some cases, it is also used by bacterial pathogens to attack higher eukaryotic host organisms, for example mammalian cells. The new research discovered that bacteria can also use the Type VI secretion system to attack fungal cells, including pathogenic fungi like Candida albicans. Additionally, the Coulthurst lab have identified the first anti-fungal effector proteins delivered by the Type VI secretion system and shown that they are potent anti-fungal toxins with distinct mechanisms.

Dr Coulthurst said, “Since microbial fungi and bacteria frequently co-exist in mixed communities, including polymicrobial infections, this discovery has significant implications for understanding the composition and dynamics of many microbial communities.”

The work has been selected by Nature Microbiology for a News and Views article.