Researchers have found 76 previously unknown genes that make bacteria resistant to last-resort antibiotics. The genes were found while searching large volumes of bacterial DNA.

The findings showed that several of these resistance genes can provide bacteria with the ability to degrade carbapenems -- most powerful class of antibiotics used to treat multi-resistant bacteria."Our study shows that there are lots of unknown resistance genes. Knowledge about these genes makes it possible to more effectively find and hopefully tackle new forms of multi-resistant bacteria", said lead author Erik Kristiansson, Professor at Chalmers University of Technology in Sweden."The novel genes we discovered are only the tip of the iceberg. There are still many unidentified antibiotic resistance genes that could become major global health problems in the future," Kristiansson said.

The increasing number of infections caused by antibiotic-resistant bacteria is a rapidly growing global problem. Disease-causing bacteria become resistant through mutations of their own DNA or by acquiring resistance genes from other, often harmless, bacteria."The more we know about how bacteria can defend themselves against antibiotics, the better are our odds for developing effective, new drugs", explained co-author Joakim Larsson, Professor at the University of Gothenburg in Sweden.In the study, published in the scientific journal Microbiome, the researchers identified the novel genes by analysing DNA sequences from bacteria collected from humans and various environments from all over the world.

They developed new computational methods to find patterns in DNA that are associated with antibiotic resistance. By testing the genes they identified in the laboratory, they could then prove that their predictions were correct.The next step for the research groups is to search for genes that provide resistance to other forms of antibiotics.