Starving superbugs, then poisoning them

Adelaide researchers have developed and patented a novel approach to fight superbugs, like golden staph, by targeting the bugs’ favourite food—iron.

Dr Katharina Richter and colleagues from the University of Adelaide have commenced the first human trials of the treatment at the Queen Elizabeth Hospital.

Superbugs, or antibiotic-resistant bacteria, cause 700,000 deaths globally every year as existing antibiotics can’t effectively kill them.

The threat from superbugs to human health is likely to worsen, with the World Health Organization predicting by 2050, 10 million people will die each year due to antibiotic resistance.

New weapons are needed to fight antibiotic-resistant bacteria.

Katharina is targeting how bacteria consume iron, to disrupt their ability to cause disease, make them vulnerable and ultimately kill them.

“Iron is like chocolate for bacteria. It gives them energy to grow, cause disease, and withstand attacks from our immune systems and antibiotics,” says Katharina.

“Using two different compounds, we first starve the bacteria of iron and then feed them the bacterial equivalent of poisonous chocolate, which the hungry bacteria find irresistible.

“This ‘double whammy’ approach has defeated superbugs like golden staph in laboratory and animal studies,” she says.

The treatment is being trialled to help patients with antibiotic-resistant sinus infections—with the two compounds included in a wound-healing gel.

“The treatment is locally applied at the infection site, precisely where it is needed without interfering with the entire body,” says Katharina.

“In our studies so far, we haven’t observed any side effects. Moreover, the risk for resistance is low as bacteria are unlikely to become resistant to their preferred food.”

In the future, Katharina hopes the therapy can be refined so it can also be used to treat other superbug infections.

The team are recruiting patients with chronic recurring sinus infections for the trials.

“We are hoping that this treatment will improve the quality of life for patients after sinus surgery,” says the trials’ principal investigator Professor Peter-John Wormald. Professor Wormald is an ear, nose and throat surgeon at the Queen Elizabeth Hospital and chair of Otolaryngology, Head and Neck Surgery at the University of Adelaide.

“By better treating the bacteria causing their infections we hope to extend the period of time patients are symptom-free, and potentially reduce their need for further surgery.”

Katharina completed her PhD at the University of Adelaide in 2017. Her doctoral research was partially funded by The Hospital Research Foundation. She is now continuing this research as a postdoctoral researcher at the University of Adelaide and the Basil Hetzel Institute for Translational Health Research. Katharina recently won the Pitch it Clever Delegates’ Choice Award at the 2018 Universities Australia Higher Education conference.

Katharina was the South Australian winner of Fresh Science, a national program that helps early-career researchers find and share their stories of discovery.

In 2017 Fresh Science celebrated its 20th birthday, and ran in every mainland state with 140 early-career researchers nominating for the five Fresh Science events held last year in Brisbane, Adelaide, Sydney, Melbourne, and Perth.

Fresh Science South Australia was supported by the University of Adelaide, the South Australian Museum, Flinders University, the University of South Australia and New Scientist.

For interview

Dr Katharina Richter Basil Hetzel Institute for Translational Health Research; The University of Adelaide katharina.richter@adelaide.edu.au, +61 (0)412 693 225

Media contact

Crispin Savage The University of Adelaide, crispin.savage@adelaide.edu.au, +61 (0)8 8313 7194

Suzannah Lyons Science in Public (for Fresh Science), suzannah@scienceinpublic.com.au, +61 (0)3 9398 1416, +61 (0)409 689 543

Banner image: Dr Katharina Richter looking at a specimen of golden staph, one of the superbugs she is looking to defeat with this treatment. (Credit: Russell Millard, The University of Adelaide)