Australian researchers have been examining the use of short chains of proteins (or peptide polymers) for the elimination of pathogenic bacteria. The peptides have been developed at the Melbourne School of Engineering.
The peptides are being considered as part of the strategy to address the phenomenon of antibiotic resistance.
The research project is led by Professor Greg Qiao. In his research brief, Professor Qiao explains why the search for mechanisms to kill antibiotic resistant organisms is important: “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.”
The star-shaped peptide developed has, in laboratory tests, proved effective in killing bacteria known to be resistant to a range of antimicrobials (such as Gram-negative bacteria). The developed peptides are non-toxic to the human body, 100 times below the toxicity threshold were they could harm red blood cells.
The testing to date has been performed in animal models. Here target populations of pathogens were eliminated, with no sign of resistance developing. One reason why the peptides offer an effective solution is because, unlike antibiotics, they can kill bacteria through multiple pathways. The most effective kill mechanism is through damage to the bacterial cell wall and the resultant leakage of cellular components.
The findings are published in the journal Nature Microbiology, in a paper headed “Combating multidrug-resistant Gram-negative bacteria with structurally nanoengineered antimicrobial peptide polymers.”
Investigations into antimicrobial peptides are being looked at by different research institutes. In related news, a new antibacterial agent termed a peptide-conjugated phosphorodiamidate morpholino oligomer is showing promise. The chemical is a synthetic analogue of DNA that has the ability to silence the expression of specific genes within bacterial cells.
