A New Possible Alternative To Antibiotics Has Been Found


Star-shaped Polymers to replace Antibiotics

Not that long ago, roughly 100 years in the past, during WWI, one of the deadliest plights to have ever hit mankind emerged in the form of influenza, or more commonly known as the Spanish Flu. Not receiving enough attention, on the account of all the warring going on, this illness killed off around 100 million people; more than five times the number of people who actually died in the war. Due in part to the squalor conditions at the time, as well as the shifting of people all across the globe, influenza reached all corners of the world, with the exception of a remote, small island somewhere in the Amazon basin.

Neutrophil and Methicillin-resistant Staphylococccus aureus (MRSA) Bacteria. Image credits NIAID / Flickr.
Neutrophil and Methicillin-resistant Staphylococccus aureus (MRSA) Bacteria.
Image credits NIAID / Flickr.

But then, with the discovery of penicillin in 1928, things quickly returned back to normal, and here we are 100 years later. But as most of us know, bacteria are an adaptable lot, and recently there have been reports of these critters being able to resist all kinds of antibiotics. These are the infamous bird and swine flues we keep hearing about on the news from time to time. These are, let’s say, influenza on steroids. And when we look back at the world during WWI and compare it to today, we come to realize that we’re far, far more in number, more closely packed together, and connected like never before. All of these, together with the new antibiotic-resistant strains of bacteria, could spell a serious blow to mankind as we know it.

Luckily however, a new class of star-shaped polymers has proven effective at killing drug-resistant bacteria, opening new potential treatment options in the future. Instead of taking the usual chemical approach to the situation, a team from the Melbourne School of Engineering has chosen a more physical option, by developing these polymers, capable of killing these mutated, single-cell organisms.

“It is estimated that the rise of superbugs will cause up to ten million deaths a year by 2050. In addition, there have only been one or two new antibiotics developed in the last 30 years,” said Professor Greg Qiao from the school’s Department of Chemical and Biomolecular Engineering.

The team has been working with these peptide polymers for the past few years, looking to make them work to our advantage against this looming threat. And even if the word “polymer” doesn’t sound particularly healthy, the substance is actually harmless to the patient. Only by taking 100 times the advised dose, will these polymers become toxic to the body. That’s far better than exceeding the recommended dose of antibiotics today; that’s for sure.

Numerous tests undertaken on mice has shown these polymers being extremely effective at killing Gram-negative bacteria. This is a strain which is particularly known for quickly developing antibiotic resistance. It didn’t show any resistance when it came to this new invention, however.
“Comprehensive analyses using a range of microscopy and (bio)assay techniques revealed that the antimicrobial activity of SNAPPs [the polymers] proceeds via a multimodal mechanism of bacterial cell death by outer membrane destabilization, unregulated ion movement across the cytoplasmic membrane and induction of the apoptotic-like death pathway,” the paper reads.
One of these pathways includes ‘ripping apart’ the bacteria cell wall. Image credits University of Melbourne.

But just like any other new discovery in medicine, this one will take years before actually reaching the pharmacy shelves. In any case, Professor Qiao and his team believe that their discovery is the beginning of unlocking a new treatment for antibiotic-resistant pathogens.

The full paper, titled “Combating multidrug-resistant Gram-negative bacteria with structurally nanoengineered antimicrobial peptide polymers,” has been published in the journal Nature Microbiology.