I’ve worked with the remarkable slime mould Physarum polycephalum for many years now as both an artistic medium, and also as an engaging microorganism for my many outreach activities.

The slime mould Physarum polycephalum

In its natural environment the microbe inhabits shady, cool, moist areas, such as under decaying leaves and logs where it predates and feeds of the billions of bacteria that also reside here. If it feeds on bacteria, and indeed is exposed to them, then I reasoned that the slime mould must have some powerful bactericidal systems. With this in mind my undergraduate research project student Denford looked for antibiotic compounds in Physarum poykcephalum. He found at least one and its active against Methicillin Resistant Staphylococcus aureus.

A zone of inhibition produced by slime mould extracts in a confluent film of MRSA

The agar plate harbours confluent growth of MRSA with a well containing P. polycephalum extract in the middle. The clear zone is an MRSA inhibitory zone where the antibiotic produced by the slime mould shows bactericidal against the pathogen and prevents its growth.