New drugs could counter antibiotic resistant hospital infectionsApril 9th, 2009 - 5:36 pm ICT by IANS
Washington, April 9 (IANS) Latest research findings that lack of sufficient phosphate in a bacterium could turn it into a killer could help develop new drugs to disarm the antibiotic resistant pathogens that cause serious hospital-acquired infections.
Pseudomonas aeruginosa, a bacteria that is a common cause of lung infections, also infests the intestinal tract of 20 percent of all Americans and 50 percent of hospitalised patients in the US.
It is one of the hundreds of bacteria that colonise the human intestinal tract, usually causing no apparent harm. It might even be beneficial to its host.
However, once the host is weakened by an illness, surgical procedure or immunosuppressive drugs, the bacteria can cause infection, inflammation, sepsis (pus-forming bacteria or their toxins in the blood or tissues) and death.
Why P. aeruginosa can suddenly turn on its host has eluded researchers - until now. Scientists have long known that after an operation or organ surgery, levels of inorganic phosphate fall.
The study authors, led by scientists of University of Chicago (U-C), hypothesised that phosphate depletion in the stressed intestinal tract signals P. aeruginosa to become lethal.
To test this theory, they let worms (Caenorhabditis elegans) feed on “lawns” of P. aeruginosa and Escherichia coli grown in both low-phosphate and high-phosphate media.
Only the worms that ate P. aeruginosa with low levels of phosphate died. The researchers dubbed the phenomenon “Red Death” since unexpected large red spots appeared on the worms before they died, according to an U-C release.
“These findings provide novel insight into the mechanisms by which P. aeruginosa is able to shift from indolent coloniser to a lethal pathogen when present in the intestinal tract of a stressed host,” said Alexander Zaborin, lead author of the study and a research professional at the U-C Department of Surgery.
“It is almost as if the bacterium sense when to strike,” said John Alverdy, study co-author and professor of surgery at the U-C Medical Center. “That should come as no surprise since the bacteria are smart, having been around for two billion years.”
The study will be published in the April 14 issue of the Proceedings of the National Academies of Science.
- New discovery may help treatment of multi-drug resistant infections - Jan 06, 2011
- Bacteria fighting fungal infections - May 02, 2010
- Scientists discover E coli's Achilles heel - Jul 16, 2012
- Studying spacebound bacteria may inspire Earthbound remedies - Mar 22, 2011
- Spacebound bacteria inspire earthly remedies - Mar 22, 2011
- Probiotic bacteria 'could help in Crohn's disease therapy' - Apr 01, 2011
- Healthy bacteria could prevent obesity - May 26, 2011
- How cholera bug invades the gut - Jan 29, 2012
- New measure to treat anthrax infection - May 02, 2010
- Microbes' tricks to kill other bugs may help fight disease - Jul 26, 2011
- Bacteria can be deadly to wound-treating maggots - Feb 05, 2010
- Unique coating kills 99 percent bugs - May 11, 2012
- Diarrhea-causing bacteria turned into antiviral gene therapy agent - Feb 08, 2011
- Bugs filch copper to spread urinary infections - Jul 09, 2012
- New study offers hope to colon cancer patients - May 10, 2010
Tags: bacterium, escherichia coli, hospital acquired infections, hospital infections, hospitalised patients, human intestinal tract, immunosuppressive drugs, inorganic phosphate, lawns, lung infections, new drugs, novel insight, p aeruginosa, pathogen, pseudomonas, red death, research findings, resistant pathogens, sepsis, study authors