The findings from UCD and the University of Sheffield found the superbug can grow and divide in the presence of antibiotics.
It has been known for many years that in order to be resistant MRSA had acquired a new cell wall enzyme that allows it to survive exposure to antibiotics.
However, the researchers showed that this alone was insufficient for survival, the study published in Science said.
MRSA has also evolved an alternative division mechanism that allows it to replicate in the presence of antibiotics.
“This previously unknown mechanism is essential for MRSA resistance. By understanding the details of this process, researchers are working towards developing inhibitors that can target MRSA’s novel survival strategy,” the study said.
Author Dr Rebecca Corrigan, of UCD school of medicine, said: “This discovery is important because it helps us to understand how bacteria can survive antibiotic treatment. It is only through understanding this that we can develop new ways to treat MRSA infections.”
She said that bacteria such as MRSA have mesh-like cell walls around them that require enzymes to knit them together.
The enzymes are the targets for antibiotics such as penicillin and methicillin, which have saved millions of lives over the decades.
Professor Simon Foster, of the University of Sheffield, said: ”This research is very exciting as it has not only uncovered a new mechanism for MRSA – that was hiding in plain sight – but also the ability of the bacteria to divide in an alternative way.
“These findings have important ramifications for the development of new antibiotics, but also for understanding the fundamental principles that underpin bacterial growth and division.
“This will provide new ways to tackle this dangerous infectious organism.”
Prof Jamie Hobbs, from the University of Sheffield, said: “We could not have made the discoveries without this synergy, fusing world-leading microscopy with genetics and microbiology.”
The next step is to find out how MRSA is able to grow and divide in the presence of antibiotics using the new mechanism that has been discovered.
Scores of patients in Ireland get MRSA bloodstream infection annually.
