Annelysis – Although we are currently focusing entirely on COVID-19 epidemics, the SARS-CoV-2 virus is not the only microbial threat we face, writes Dr. Sioux Wiles.
Back in 2014, the World Health Organization (WHO) warned that within a decade, antibiotic-resistant bacteria could pose a life-threatening risk to routine surgery, organ transplants and cancer treatment اور and the end of modern medicine. We know
Antibiotics are the cornerstone of modern medicine, used to treat infections and to protect vulnerable patients undergoing surgery or chemotherapy. The world is in dire need of new antibiotics and COVID-19 has exacerbated this problem.
In our search for new antibiotics, we have focused on the fungus, especially those found only in Autorva New Zealand. Our latest research describes the discovery of fungal compounds capable of killing mycobacteria, a family of slow-growing bacteria that is another major global air killer, Mycobacterium tuberculosis – which causes lung disease. And it kills thousands of people every day around the world.
Although most people in Aotearoa know me as the “Pink Haired COVID Woman”, for the past six years my lab has been looking for compounds that can make good antibiotics. We have focused on the International Plant Storage (ICMP) fungus, which is maintained by the Crown Research Institute Manaki Vinova and our partner Beyonc.
Our latest findings follow previous research that revealed a fungal compound with some activity against the hospital’s superbug methylene-resistant Staphylococcus aureus, known as MRSA.
One of the earliest antibiotics ever discovered, penicillin, actually came from a fungus called Penicillium rubens. With over 10,000 fungi in the ICMP database, we believe this is a treasure trove of potential new antibiotics.
For our latest study, we tested 36 cocaine collected between 1961 and 2016 from all over Atyrau, including Chatham Island. Our first interesting finding is that the species of neo-fungi are not known, suggesting that they may be unique to Autorva.
Aotearoa is famous for its famous species of animals and plants that are not found anywhere else in the world. Our fungi will not be different. And if they’re unique, they’ve come up with unique compounds that can kill bacteria.
Our second major finding is that of the 36 fungi we tested, 35 had some sort of antibacterial activity against mycobacteria. In fact, when we first started doing it, we thought we had made a mistake. We will never have this kind of success rate when screening fungus against other superbugs.
Taking a closer look at the chemistry of these fungal compounds, we found that most of them contain fatty acids that do not make good antibiotics. But we found many fungi, including two of our unknown species, which did not have antibacterial activity due to fatty acids.
We are currently working with colleagues Melissa Cadellis and Brent Cope to identify these compounds.
A long way to go.
Physicist Jim Al-Khaili once said that most scientific advances are a “dirty, complex and slow process”. Take the COVID-19 vaccine as a good example. Although we have seen many vaccines successfully and rapidly emerge through clinical trials, they are based on decades of scientific study of mRNA and lipid nanoparticles.
My lab’s search for antibiotics has its roots in the work we did a decade ago, creating tools to shine mycobacteria in the dark. Because these bacteria grow so slowly, it can take weeks to months for them to colonize the petri dish.
But they only shine when they are alive, and this technique allows us to measure the amount of light we need rather than wait for them to grow. It accelerates the process of mass antibiotic discovery.
I began to think of fungi as a possible source of new antibacterial compounds when Peter Buchanan, a fungologist at Manaki Jabba, told me about this combination. After a few years of rejected funding applications, we were finally given a small grant from Cure Kids to start the project in 2015.
One of her ambassadors, Eva, has fought a super bug infection all her life. Meeting Eva changed my relationship with my job and encouraged me to do my best to find new antibiotics.
We still have a long way to go before we have any compounds that are suitable for further development as antibiotics. We also know that many compounds fail when they pass through pipelines that carry them from the lab to clinical trials in humans.
That’s why my lab will continue to work through fungal collections as long as we can afford it. There are thousands more fungi for screening and hopefully many more unique compounds with antibiotic potential will be discovered.
* Suu Kyi is an Associate Professor of Microbiology and Infectious Diseases at the University of Auckland.
** Wells is funded by Cure Kids and NZ Carbon Farming. This work was first supported by the Morris Wilkins Center for Molecular Bio Discovery and the University of Auckland.