April 9, 2009 — Research to develop a
narrow-spectrum antibiotic that can target a particular species of
bacteria without harming the other "good" bacteria present was
described at the Society for General Microbiology meeting at Harrogate
Professor Kim Brogden from the University of Iowa attached a
broad-spectrum antibiotic to a protein that targets a receptor on a
particular bacterium’s surface. When this newly-formed narrow-spectrum
antibiotic was tested on a mix of bacteria that included the target
organism, Porphyromonas gingivalis, a cause of gum disease,
low concentrations of the antibiotic killed the P. gingivalis bacteria
but left the other two bacterial species in the mix untouched.
Antibiotics have clear clinical benefits in treating oral infections
like gum (periodontal) disease. This therapy reduces the number of
harmful bacteria in patients who have received non-surgical and
surgical treatments. Hard and soft tissue damage is much less in
patients who have received antibiotics than in patients who have not
received these drugs. Unfortunately, complications are associated with
Side effects such as nausea, vomiting, abdominal discomfort,
diarrhoea, allergic skin rashes and fever can be caused by penicillin
and related drugs. Overuse of antibiotics leads to the development of
drug-resistant bacteria. And antibiotics can kill the normal bacterial
population of the mouth, urogenital tract, and gastrointestinal tract.
This can lead to infections by opportunistic Candida albicans yeast in
the mouth and urogenital tract or the bacterium Clostridium difficile
in the gastrointestinal tract.
A targeted approach is needed to kill specific disease-causing
bacteria in complex environments, said Professor Brogden. "We are
developing an antibiotic that can target and kill a particular pathogen
without harming or altering the composition of the normal, more
beneficial bacteria in the body. Such a product would provide a variety
of new treatments for oral diseases as well as a means of prevention."
Source : Society for General Microbiology