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Finding out about FlemingWhat sort of person makes scientific discoveries like the existence of penicillin? Often quite ordinary people like you and me who just happen to be in the right place at the right time. Read on to find out more about Fleming ... Becoming a doctorAs far as we know, as a boy Alexander Fleming did not have any ambition to become a doctor. He grew up as the seventh of eight children, on a farm in Scotland. In 1900, when the Boer War broke out between England and colonies in southern Africa, Fleming and two of his brothers joined a Scottish regiment. They had a relatively pleasant war and spent quite a bit of their time shooting, swimming, and even playing water polo. When the war was over Fleming returned home to discover that his uncle had died and left him some money. His older brother, Tom, who was a successful doctor by this time, advised him to go to medical school. Alexander got very high marks in his exams and was able to select from three medical schools. He knew nothing about any of them and chose St. Mary's Hospital, in London, only because he had once played water polo against them! Fleming trained to be a surgeon and was offered a post as a surgeon at another hospital. However he was also offered a place in the Inoculation Service at St Mary's. The captain of the St. Mary's rifle club was desperate to improve his team and knowing that Fleming was a great shot he convinced Fleming to join the inoculation department in order to work with its brilliant director, stay at the hospital he knew -- and support the rifle club! Fleming decided to stay at St. Mary's, became a microbiologist and remained there for the rest of his career, working on ways to defeat infectious diseases. Fleming the microbiologistIn 1928, Alexander Fleming was researching the properties of the group of bacteria known as staphylococci. His biggest problem was that he was a very sloppy scientist, and so his culture plates were often contaminated with airborne moulds. He also often completely forgot about cultures he had set up in his rather chaotic lab. After returning from a holiday, Fleming observed that many of his culture plates were contaminated with a fungus. This wasn't unusual and he immediately threw the plates into disinfectant. As luck would have it, before he could get rid of all his contaminated plates former member of his lab dropped in to visit and he took the remaining plates to show his visitor what he has been doing. It was only then that he noticed the unusual inhibition zone around the fungus. He realized there and then that that this might be something important and for the rest of that day showed all of his colleagues the culture. He then began to study the anti-bacterial properties of the mould. The potential of penicillinFleming isolated an extract from the mould and named it penicillin after the type of mould it came from. His discovery was published but not a great deal of attention was paid to the paper. He couldn't make a concentrated extract of penicillin, the penicillin he did produce tended to be unstable and he was unable to prove that it had any therapeutic value. On one hand it was obvious that penicillin was a very powerful an antibacterial compound. His crude extracts could be diluted 1,000 times and still be effective in killing bacteria. Tests were done with various species of bacteria to show that penicillin killed a range of organisms, and also on laboratory animals to be certain that penicillin would not be toxic to them. These results were also very interesting, but how could they be used practically? Fleming continued to work on and off with penicillin between 1928-1931, but was unable to produce it in the quantity necessary for testing practical applications. For some time this did not dampen Fleming's enthusiasm and he continued to talk of its great potential value in medicine. Unfortunately, this had the opposite effect on his colleagues than the one he wanted. Fleming was known as a dreadful lecturer and bad speaker - he had no gift for inspiring others. Nothing was really happening in his work anyway and people got tired of hearing about what he was doing with penicillin eventually.. There were many people who doubted that the discovery would be of any value - and indeed eventually even Fleming himself began to wonder if the mould would ever be of any real use. He began working with two new antibacterial drugs which were developed and had stopped working with penicillin by 1934, although his interest remained. Click here to visit the Nobel web site to read the text of a lecture written by Sir Alexander Fleming in 1945, along with lots of photos of his original plates and cultures.
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The germ theory of disease
