Lightbulb moment: Associate Professor Ashley Buckle and Dr Sheena McGowan of the Monash School of Biomedical Sciences have deciphered the atomic structure of PlyC, a protein which could be an alternative to antibiotics. Picture: Sam Stiglec
FOR years, Sheena McGowan was told her efforts in working out the structure of the antibacterial protein PlyC would be in vain.
The protein, known for its effectiveness in fighting harmless sore throats to life-threatening cases of toxic shock, had been studied since the early 1900s but researchers had never been able to determine what it looks like.
The process became so frustrating that DrMcGowan, of Monash's school of biomedical sciences, began to lose hope.
She spent years growing protein crystals and, because the Australian synchrotron wasn't built yet, sending them to Chicago to have x-rays fired through them.
"By the end of 2007, I had written to our collaborators in the US and said it's just not possible," she recalls.
Her colleague, Associate Professor Ashley Buckle, remembers telling her to abandon what looked like a pointless endeavour.
But then, after more than half a decade, one of the crystals suddenly showed some results.
"There was a moment when, on my screen, I could see something that I knew meant we were on the right track and we were going to get there," Dr McGowan says. Atom by atom, DrMcGowan, Associate Professor Buckle and their colleagues at the University of Maryland and Rockefeller University pieced together what PlyC looked like, paving the way for a new alternatives to antibiotics.
The work by Dr McGowan and and Associate Professor Buckle comes at a crucial time. The World Health Organisation has warned about the growing health threat of antibiotic-resistant bacteria.
"The truth is, we're going to need something new in the coming decades. The bacteria are gaining a lot of resistance to the antibiotics we have," Dr McGowan said. "We don't know when the antibiotic coverage will run out. It's likely to be a couple of decades but if we consider a society without coverage of antibiotics, it's a very scary world where a sore throat or a cut could become a life-threatening disease."
PlyC is known for being able to kill bacteria involved in sore throats, impetigo, pneumonia and even a flesh-eating disease.
Up until now, scientific progress has been hindered because researchers they had no idea what the molecule looked like.
Associate Professor Buckle says the breakthrough is a fundamental step forward that stops scientists from "working in the dark".
"The structure and shape answers questions, helps people realise what it means and tells you a bit of how it works."
"Determining the structure is just going to accelerate the next five years or ten years of development. This is really critical."
Dr McGowan agreed. "This kind of research, this basic biology, needs to be done early. We need to invest in this kind of research so we can develop these therapeutics so they're safe and effective when we need them.
"Biology that we and the US have been doing in this particular project is just fundamental to succeeding in getting something on a shelf that humans can use."