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[Tvoivozhd <tvoivozd AT infionline.net>]

Phages came before antibiotics---they were not well understood so their 
efficacy was not reliable, but a hell of a lot better than doing 
nothing---or praying, which is certainly doing nothing

   News in Science <http://www.abc.net.au/science/news/default.htm>

   *News in Science <http://www.abc.net.au/science/news/default.htm>*

   *News in Science - Blasting bugs without antibiotics - 02/11/2004 *

   [This is the print version of story
   http://www.abc.net.au/science/news/stories/s1232769.htm]


       Blasting bugs without antibiotics

   Maggie Fox
   Reuters

   Tuesday, 2 November  2004 
   Bacteria
   Bug busting: maybe harnessing a bug's own natural survival mechanism
   is the key to fighting infection /(Image: iStockphoto)/

   Pitting one germ against the other is behind at least two new
   methods of fighting infection without antibiotics, a U.S. meeting
   has heard.

   One method uses deadly enzymes, made by viruses called
   bacteriophages, which precisely execute bacteria. Another uses
   compounds made by one bacteria to shut down another without actually
   killing it.

   Each illustrates potential new ways to fight the growing problem of
   superbugs, bacteria that have mutated to resist most or all
   antibiotics used against them.

   The methods might also work against biological agents such as
   anthrax, the researchers told a meeting sponsored by the American
   Society for Microbiology <http://www.asm.org/>.

   A single squirt of the bacteria-killing enzyme may keep an infected
   person from sneezing out bacteria for up to a week, said Dr Vincent
   Fischetti of Rockefeller University <http://www.rockefeller.edu/> in
   New York.

   "These are enzymes that, basically, punch a hole in the bacteria and
   cause them to explode," Fischetti said.

   They have used them to decontaminate animals of bacteria such as
   Group A streptococci and staphylococci.

   "We can eliminate these organisms from the noses of these animals,"
   Fischetti said.

   They also tried it intravenously against the anthrax bacillus.

   "We could save 90% of the animals with a single dose of the enzyme,"
   said Fischetti, whose work is funded by the U.S. Defense Advanced
   Research Projects Agency <http://www.darpa.mil/>.

   The researchers are planning tests in mice, monkeys and perhaps
   rabbits and will use the results to seek permission to test the
   enzyme for safety in humans.

   New U.S. Food and Drug Administration <http://www.fda.gov/> rules
   allow researchers to test drugs against potential biological agents
   in two animal species, as there is no ethical way to test them in
   people.

   "These enzymes work instantly," Fischetti said, and could be sprayed
   into the nose in a saline buffer.

   And he said there was no evidence, yet, that bacteria can develop
   mutations that will allow them to evade these enzymes.

   *Using bugs to blast bugs*

   Dr Richard Novick and colleagues at New York University
   <http://www.nyu.edu/>'s medical school looked specifically for ways
   to stop bacteria from attaching to and killing cells in the body.

   They found peptides, short pieces of proteins, regulate this behaviour.

   "We happen to have hit on one of these that provides an Achilles
   heel of the organism," Novick said.

   "We can disarm the organism ... simply by introducing one of these
   inhibitory factors."

   The first three hours are critical for infecting bacteria to get a
   foothold, Novick said. The peptide holds the bacteria in check just
   long enough to give immune system cells time to get there and
   destroy the invaders.

   The peptide, called auto-inducing peptide, affects signalling within
   the bacteria.

   /Staphylococcus aureus/, one of the worst causes of infections
   caught in hospitals, have evolved into four different strains, each
   with a different version of this peptide.

   "Remarkably and conveniently for us, the peptide produced by any one
   of the subspecies blocks activation of the virulence response by any
   of the others," Novick said.

   They created a version of the peptide in the lab that blocks all
   four and are now trying to improve it so it works even more broadly
   and lasts longer.


             Related Stories

   Antibacterial soap won't cut infections, News in Science 2 Mar 2004
   <http://www.abc.net.au/science/news/stories/s1056419.htm>
   Gene swap led to superbug, News in Science 28 Nov 2003
   <http://www.abc.net.au/science/news/health/HealthRepublish_999126.htm>
   Bacteria cures ear infection, News in Science 31 Jan 2001
   <http://www.abc.net.au/science/news/stories/s239250.htm>


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