First 398 words of the document:
NEED FOR NEW DRUGS
New diseases emerging
Many diseases with no effective treatments
Antibiotic treatments becoming less effective - microorganisms that cause disease beginning
HOW ARE NEW DRUGS DISCOVERED?
Accident, Traditional medicine, Observation of Wildlife, Modern Research
Concentrated on tropical plants
Chemical fingerprint technology being used to screen more chemicals
Learn how bacterium produces antibiotics by finding out what its genes do
Research into the way microorganisms cause disease
Sequencing the genes that code for CD4 receptor or other receptors - compare DNA of a
person with that of a plant or microorganism identifying potential medicinal drugs from DNA
The natural medicines:
Hippocrates used an extract from willow bark to relive pain and fever.
In recent decades, discovery of natural drugs has concentrated on tropical plants. Owing to
their great diversity, there are hopes that there may be many new medicinal drugs to
Most antibiotics developed over the past 50 years come from the bacterium Streptomyces.
Biologists hope to learn how the bacterium produces antibiotics by finding out what its
Pharmaceutical companies have been conducting research into the way microorganisms
cause disease. Many make us of receptors on plasma membranes. If the receptor site can
be blocked by a drug, then the disease-causing pathogen cannot gain access to the cell. The
next step is to find a drug that could block the receptor without causing major side effects.
1) Explain how our ancestors might have discovered that poppy seeds contain a chemical that
has anaesthetic properties.
Poppies grow among other crops. The seeds may be incorporated into food products,
such as bread, by accident. There may even have been added to give extra taste or extra
nutrients. The effects of poppy seeds may have been discovered by accident- someone
who ate bread containing seeds found that a wound did not hurt as much as before.
2) How did Fleming discover penicillin?
He was conducting experiments on bacteria. He noticed that his agar plates did not
contain bacteria in a region that had accidentally been inoculated with a fungus. The
fungus appeared to prevent the growth of bacteria.