Milena von und zur Muhlen

Bacterial “presisters” – Antibiotic tolerance in action

Having completed my BSc at the University of Sheffield, I decided to stay on and complete a PhD here too. I do really love the city and it’s proximity to the outdoors.

I am working in Prof. Simon Foster’s lab on antimicrobial resistance and persistence. We use novel cell wall staining dyes and super-resolution microscopy to investigate how antibiotics kill Staphylococcus aureus and why some of them survive.

The spread of antibiotic resistance is alarming. An important phenomenon is called “persistence” whereby a small proportion of the bacteria are able to survive antibiotics due to their physiological status (slow or nongrowing), leading to treatment failure. Studies are hampered by our inability to identify potential “persisters”. Using a new technique to fluorescently label nascent cell wall synthesis we have developed the ability to monitor the physiological status of every individual cell within an entire population. This has identified a small proportion of “nongrowers” and oscillating “stop-start growers”. Thus for the first time we can identify potential “persisters” within a population as “presisters” before antibiotic intervention, via their fluorescent labeling pattern. This permits the molecular basis of their status to be determined and targeted by novel approaches.