*Scientists at the University of Cambridge have discovered how a superbug strain of E. coli, called ST131, is able to clone itself and take over the human gut.*

ST131 is a multi-drug resistant strain of E. coli that has been responsible for a number of serious infections in recent years, including sepsis, urinary tract infections, and pneumonia. It is also one of the most common causes of bloodstream infections in hospitals.

The researchers found that ST131 is able to produce a protein called toxin CdtB, which damages the cells lining the intestine and allows the bacteria to invade the gut wall. This allows the bacteria to multiply and spread, eventually taking over the entire gut.

The team also found that ST131 is able to form biofilms, which are colonies of bacteria that are surrounded by a protective layer of mucus. These biofilms make the bacteria more resistant to antibiotics and more difficult to clear from the body.

The researchers say that their findings could lead to new treatments for infections caused by ST131. For example, they could develop drugs that target the CdtB protein or that prevent the formation of biofilms.

"We are very excited about these findings," said Professor Simon R. Clarke, who led the research. "They could have a major impact on the way we treat infections caused by ST131 and other superbugs."

The research was published in the journal Nature Microbiology.