Bacterial protein prolonged life of infected host animals with no increase in cancer
A DNA-damaging protein in typhoid bacteria might keep infected animals alive and provide a safe haven for the microbes.
Typhoid toxin, a protein produced by the typhoid fever-causing bacterium Salmonella enterica Typhi, tears DNA molecules apart. But the protein actually prolonged survival and reduced gut inflammation in mice infected with S. enterica, an international team of researchers reports April 7 in PLOS Pathogens.
The deadly, mouse-infecting version of S. enterica doesn’t normally make the typhoid toxin. So the scientists modified mouse S. enterica with typhoid toxin genes from the human-infecting strain responsible for the high fever, headache and rash of typhoid fever. The team thought that typhoid toxin’s DNA slashing might cause tumors, but in mice fed the toxin-making S. enterica, no increased cancer risk appeared compared with