CHICAGO, April 13 (UPI) -- U.S. medical researchers say they have discovered a lack of the mineral phosphate can turn a common bacterium -- Pseudomonas aeruginosa -- into a killer.
University of Chicago scientists said their finding could lead to new drugs that would disarm the increasingly antibiotic-resistant pathogen rather than kill it.
Pseudomonas aeruginosa, one of the most serious hospital-acquired pathogens, is a common cause of lung infections. It is found in the intestinal tract of 20 percent of all Americans and 50 percent of hospitalized patients in the United States, the scientists said. It is one of hundreds of bacteria that colonize the human intestinal tract, usually causing no apparent harm.
But once the host is weakened by an illness, surgical procedure or immunosuppressive drugs, the researchers said Pseudomonas aeruginosa can cause infection, inflammation, sepsis and death.
The researchers said it's been long known that after an operation, levels of inorganic phosphate fall. The researchers hypothesized phosphate depletion in the intestinal tract signals Pseudomonas aeruginosa to become lethal.
To test their theory, they let worms (Caenorhabditis elegans) feed on Pseudomonas aeruginosa and Escherichia coli grown in both low-phosphate and high-phosphate media. Only the worms that ate Pseudomonas aeruginosa with low levels of phosphate died.
The research is reported in the Proceedings of the National Academy of Sciences.
