Scientists have modified the antibiotic vancomycin to attack the antibiotic-resistant bacteria VRE in three ways, making it harder for bacteria to develop resistance. Vancomycin was previously used to treat VRE but the bacteria became resistant; the reengineered version kills VRE without signs of developing resistance. If further tested successfully, the modified vancomycin could help address the growing problem of antibiotic resistance which occurs when antibiotics are overused and bacteria mutate.

1. REENGINEERED ANTIBIOTIC
Antibiotics are medicines, or drugs, used to
treat illnesses and infections caused by bacteria.
(They have no effect on viral infections, or dis-
eases caused by viruses.) Some types of bacteria
have now become resistant to antibiotics.
Therefore, these medicines can no longer be
used to treat the diseases caused by the bacteria.
One popular antibiotic is called
vancomycin. It was first used in the 1950s. In
recent years, doctors have become worried
about a bacterial strain known as VRE
(vancomycin-resistant enterococci).
It is hard to treat. VRE has been found in some
hospitals. It can cause dangerous infections in a
wound or a person’s bloodstream. In the past,
vancomycin was used to treat the bacteria.
Some other antibiotics can treat VRE. Yet this
bacterial strain is now resistant to vancomycin.
The World Health Organization (WHO)
works closely with the United Nations (U.N.). It
advises governments on health treatments and
disease prevention. Recently, the WHO
described VRE as “one of the drug-resistant
bacteria that pose the greatest threat to human
health”.
Scientists in the U.S. have been trying to
modify, or reengineer, vancomycin. Recently,
they an-nounced that they had succeeded in
altering the antibiotic. The sci-entists say that
the “modification” attacks VRE and other
bacteria in three different ways. This makes it
much harder for the bacteria to de-velop any
future resistance.
The first antibiotic was found by accident.
Alexander Fleming (1881 – 1955) discovered it.
He was a British scientist. One day in 1928,
Fleming was tidying his laboratory. He checked
some Petri dishes that had been left on a bench.
(Julius Richard Petri invented these dishes.
He was a German scientist who died about 100
years ago.) These circu-lar, shallow, glass dishes are
used to grow tiny microbes. Fleming’s Petri dishes
were covered with a type of bacteria. He noticed
some mold, or fungus, on one of them. It was in the
shape of a ring. There were no bac-teria in the area
around it.
Fleming guessed correctly that something in the
fungus had killed the bacteria. Further research
showed that it also killed other types of bacteria.
Fleming managed to make a liquid from the fungus.
He called it penicillin. Fleming continued to
experiment with the bacteria-killing liquid. Yet, he
was never able to make penicillin in large amounts.
Also, it seemed to act very slowly.
In the 1940s, Howard Florey and Ernst Chain began
studying penicil-lin.
These two scientists worked at Oxford University, in
Britain. They managed to solve the quantity and
slow acting problems. Within a short time,
penicillin became known as “a wonder drug”.
People were amazed at how quickly it cured
infectious diseases. In 1945, Fleming, Florey and
Chain were awarded a Nobel Prize for their work.
Since the discovery of penicillin, many other
antibiotics have been found or developed. Fungi and
certain types of bacteria naturally produce some
antibiotics. Others are man-made. Antibiotics have
be-come very important for many types of medical
treatment. For instance, people who have
operations, or sur-gery, are given antibiotics.
Without them, cuts made by a surgeon could
become infected easily.
Only three new antibiotics have been developed
in the last 25 years. Most medical experts agree
that anti-biotic resistance is now a serious prob-
lem. An antibiotic used too frequently is one
reason for this. Frequent use encourages bacteria
to change, or mutate. Antibiotic resistance is a
good example of how evolution works. Fleming
foresaw this problem soon after he discovered
penicillin.
Antibiotics disrupt a bacterium’s cell membrane.
They make it burst open. The American scientists
say that the modified vancomycin can do this in
three different ways. This is the first antibiotic
that is able to do this. In the scientists’ laboratory,
the modified vancomycin killed VRE and other
bacteria. What’s more, after repeated use, the
VRE showed no signs of becoming resistant.
More work has to be done before the
reengineered vancomycin is given to humans. The
new antibi-otic will be tested on animals. The
scientists will also have to work out how to make
the antibiotic in large quantities.
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