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Biologists at Rockefeller University are testing a new way to fight dangerous
bacteria, including things like deadly anthrax.
As this ScienCentral News video reports, it pits nature against nature.
The New Antibiotic
At Rockefeller University in New York City, microbiologist Vincent
Fischetti and his team discovered a new way to kill bacteria. The team
uses chemicals they call "lysins," which are produced by viruses,
to kill bacteria.
Fischetti explains what a lysin is and does: “A lysin is an enzyme produced
by a bacteriophage.
A bacteriophage is a virus that infects bacteria. So when a bacteriophage
infects a bacterium, it enters the bacterium and replicates and produces hundreds
of progeny inside that bacterium. At the end of this growth cycle it has a
problem: It has to get out of the bacterium. And it solves the problem by
producing an enzyme called ‘lysinâ€™ that punches a hole in the
bacteria, causing the bacteria to explode."
The phages are very specific about which bacteria theyâ€™ll attack. For
every bacterium there is a bacteriophage that can kill it and each makes a
specific lysin. So far the bacteria have not been able to become resistant
to any of the lysins, even though Fischetti has tried to force such resistance.
What does all this mean for us?
The team is now testing specific lysins that kill dangerous bacteria such as,
(which cause strep throat), and staphylococci,
(which cause many serious staph infections), and enterocci
(which cause resistant hospital infections).
Fischetti says there are various environments where there is a need to control
these organisms. “If we can eliminate these organisms safely we can
eliminate a lot of disease," he says. "We never had a reagent that
can specifically remove these organisms from such membranes, and we can now
use those enzymes to remove these organisms from the population and thus reduce
infection. So I think in hospital environments, in nursing homes and also
in day care centers—where we have to control these types of organisms—we
may now have a reagent to control those bacteria, to reduce infection in these
We may now have a new way to kill nasty bacteria that affect us more often
than we would prefer. These new bacteria killers are not available today,
but Fischetti anticipates them to be available to the general public in five
to six years. Soon we may be picking up more than our standard cold medicine
at our local pharmacy.
“We anticipate that these enzymes will be in liquid form," says
Fischetti, "where we can spray them in orally or nasally. Because all
we need is contact with the enzyme to the bacteria in order for the kill to
occur. It occurs instantly.”
Such a spray would be very convenient for parents trying to knock out the common
throat infections that their children tend to pass among one another. According
to Fischetti, we already carry this bacteria in our throats up to 40 percent
of the time—even without being sick the bacteria is in us already, just waiting
for a chance to attack.
And speaking of attacks…
Last fall Fischetti's group showed that the lysin produced by the virus that
attacks anthrax can not only kill anthrax bacteria, but can also is used to
design a quick,
portable anthrax detector. Currently the team is trying to create a safe
way to use these lysins to treat humans should another anthrax attack happen.
“Weâ€™re testing against anthrax right now. We are able to kill the
organism directly in the blood,” he says. “Weâ€™ve been able
to do those experiments where we could do an IV drip of the enzyme in the
blood to control these organisms. So were anticipating doing these anthrax
enzymes with authentic anthrax this coming summer in mice or rabbits, then
moving to the monkeys. If thatâ€™s successful, we will then move to safety
studies in humans, and at that point we will probably stockpile it in the
event of an attack.”
The research was funded by the Defense
Advanced Research Projects Agency (DARPA).