Researchers at the Indian Institute of Technology Bombay have developed a DNA-based strategy that may help make drug-resistant bacteria responsive to antibiotics again, offering a fresh approach to the global antimicrobial resistance crisis. The work, led by Prof Ruchi Anand and Prof. P. I. Pradeepkumar of the Department of Chemistry, focuses on protecting existing antibiotics rather than creating entirely new ones.
Antibiotics are widely used to treat infections such as pneumonia, tuberculosis, urinary tract infections and bloodstream infections, and are also given to prevent infections during surgeries, organ transplants and chemotherapy. But their widespread and often indiscriminate use has accelerated antimicrobial resistance, making it harder to treat common infections and increasing pressure on healthcare systems.
In two recent studies, the IIT Bombay team used short DNA sequences called aptamers to block enzymes that help bacteria resist antibiotics. Aptamers are synthetically produced, relatively stable and easier to modify than conventional drugs, according to the institute’s report.
Prof Anand said improving existing drugs may be a more practical route than pursuing new antibiotics from scratch. “Given the long, expensive path from drug discovery to clinic, improving existing drugs may be a more practical route. We know its safety and effects over the years and can use existing resources,” she said.
The first study examined aptamers that performed well in laboratory assays, but the researchers noted that DNA molecules face two major hurdles inside bacteria: they can be broken down by nucleases and may not easily cross bacterial membranes. To address that, the second study explored a liposome-based delivery system, using tiny bubble-like spheres made of fatty molecules that resemble biological cell membranes.
The team said liposomes could help carry the DNA into bacteria more effectively, while chemical changes at the DNA ends may improve stability further. Prof Anand said, “Synthesising DNA is relatively straightforward, and liposome formulations are already widely used in medicine. Stability can be further improved by chemical modifications at the DNA ends – strategies routinely used in nucleic acid therapeutics.”
If developed for therapeutic use, the aptamer could be administered alongside existing antibiotics, blocking resistance mechanisms and potentially restoring the drugs’ effectiveness. However, the researchers cautioned that more work is needed, including animal studies and pharmacokinetic analyses, before the approach can move closer to clinical use.
Prof Anand said the core idea is to revive older drugs rather than replace them. “But the beauty of the approach lies in the fact that we can re-sensitise old antibiotics,” she said.
The findings add to growing scientific efforts aimed at tackling antimicrobial resistance, which the World Health Organisation has described as one of the most serious global health threats. For hospitals and patients alike, a strategy that helps preserve the usefulness of existing antibiotics could have major implications if it eventually proves effective in humans.
