In a breakthrough development, failed antibiotics may hold the key to the weed killers of the future, according to researchers at the University of Adelaide. Initially designed to combat tuberculosis but never making it past the laboratory stage, a modified version of the molecule has proven effective in eradicating troublesome weeds without harming bacterial or human cells. Lead researcher Tatiana Soares da Costa from the University of Adelaide’s Waite Research Institute described the discovery as a potential game changer for the agricultural industry, as many weeds have developed resistance to existing herbicides, resulting in significant financial losses for farmers.

The Herbicide and Antibiotic Innovation Lab at the University of Adelaide identified molecular similarities between bacterial superbugs and weeds, enabling them to exploit these connections. By chemically altering the structure of the failed antibiotic, researchers successfully disrupted the production of lysine, a crucial amino acid for weed growth. This approach marks a departure from traditional herbicides on the market, as there have been few new herbicides with novel mechanisms of action introduced in the past four decades.

Weeds pose a substantial economic burden on the Australian agriculture industry, costing over $5 billion annually. Of particular concern is the prevalence of annual ryegrass, a highly problematic and costly weed in the southern region. By repurposing failed antibiotics as herbicides, researchers hope to expedite the development of more effective weed killers that specifically target invasive and damaging weeds.

Lead researcher Tatiana Soares da Costa emphasized that using failed antibiotics as herbicides will not contribute to antibiotic resistance, as the herbicidal molecules selectively target weeds without affecting human cells. This discovery not only benefits farmers but also holds promise for the development of new weed killers that can address unwanted growth in residential areas.

The findings of this research have been published in the journal Communications Biology. The team led by Soares da Costa plans to further explore repurposing other failed antibiotics to discover additional herbicidal molecules. They also aim to collaborate with industry partners to bring new and safe herbicides to the market. This innovative approach could potentially lead to broad-spectrum herbicides capable of targeting a wide range of weeds, offering a significant advancement in weed control methods.