Penicillin for the treatment of war casualties was first produced in the United States of America. Its effects were miraculous. Despite living in Britain since the age of 23, Florey remained Australian in accent and outlook. In he visited Australia to discuss the local production of penicillin and to report on the state of medical research in the country of his birth.
He produced a paper that played a major role in establishing the Australian National University. From to he was closely connected with the development of the university, particularly of the John Curtin School of Medical Research.
Offered the directorship of the school in , he temporized and did not finally decline until Meanwhile, as 'adviser' to the school , he was effectively its non-resident head. He opened the school's permanent building in and became chancellor of the university in Florey was reserved, but sure of himself.
A splendid experimentalist, he had no liking for speculation or abstract ideas. He was intensely hard-working and expected the same devotion from his colleagues and students. Although he had no time for administrators—'paper-shufflers', as he called them—when thrust into senior administrative positions he proved to be an excellent chairman. He was a man of vision and above all a man who got things done: 'few people can have made better use than Florey of eminence stemming from a major role in a great discovery'.
Outstandingly successful as president of the Royal Society, London, he reorganized the institution, greatly expanded its research-professorship programme and secured magnificent new premises at 6 Carlton House Terrace. As a boy and a young man, Florey had been good at sport and he continued to play tennis with enthusiasm into his fifties.
There he began to assemble the team- in itself an unusual approach in those more individualistic days -which would crack the bacterial infection problem. As one of his biographers, the late Robert Gwyn McFarlane Howard Florey: The Making of a Great Scientist , said: "Florey was a rough, tough Australian, completely uncompromising, rather prickly, very energetic and tense as a coiled spring.
And he brought to his work this extraordinary dedication which was very infectious, in such a way that he really could collect a team of people who became almost as dedicated and enthusiastic as himself. Indeed, at 43 he had published so many important research papers that he was elected to the prestigious Royal Society in the United Kingdom. Two decades later, Florey was elected its president, the first pathologist and the first Australian to obtain that post.
His interest in penicillin was born amid a broader surge of scientific inquiry into the drug-making potential of biological compounds produced by the human body, animals and plants.
Chain was working on snake venom but Florey and others attracted his interest to a substance known as lysozyme, an antibacterial enzyme found in tears and nasal secretions. Together, Chain and Florey decided to systematically survey all known natural antibacterial substances. Among those substances was a simple mould discovered years earlier in London by the Scottish researcher Alexander Fleming, in one of the greatest and most famous pieces of luck in medical research.
Fleming returned to his laboratory from a twoweek holiday in to find that a petri dish with a culture of bacteria left uncovered on his desk had been settled on by a mould spore that had begun to grow to about the size of a cent coin.
Around the rim of the mould the bacteria were dead. At first, Fleming merely noticed the mould then threw it into a bucket. He later retrieved it and tinkered with it experimentally. He had earlier made a study of different antibacterial substances and discovered the antibacterial enzyme lysozyme, so the mould interested him enough to cultivate it.
The green mass that grew on the surface of a broth had such a strong effect on bacteria that even when diluted to times, it completely prevented the growth of staphylococci bacteria. It turned out to be a species of the penicillium group of moulds - penicillium notatum -described for the first time only in Fleming discovered that penicillin was highly effective against many different kinds of bacteria.
He performed basic tests on white blood cells and mice to show that it was not toxic and had a little success testing its effect on infected wounds. He published a brief scientific report about it in but, believing it to be too difficult to work with and not showing enough promise beyond being a possible disinfectant of skin wounds, he moved on.
He went to see this lady and said to her, 'This mould that I saw you with She said, 'Yes, he cultured it and he gave us a piece of it, and we've kept it alive ever since'. Science is so full of pieces of serendipity. In , Florey and Chain began to study the mould more closely and found that it grew slowly and had special needs.
They experimented with different growing mixtures, including Marmite, malt extract, meat and yeast extracts and studied its growth rate. They began to work out how to extract the active penicillin compound from the brown juice that accumulated beneath the surface layer of green mould.
Funds were short despite Florey's many urgings for more financial support, so in the Australian tradition of making do with whatever materials were to hand, he encouraged his team to experiment with growing the mould in biscuit tins and various dishes and pans. Hospital bedpans turned out to be the best-shaped growing containers. Old dairy equipment, a letterbox and an aquarium pump were among the items pressed into service to make the first penicillin.
It turned out to be highly unstable stuff. The scientists quickly moved on from filtering the juice through parachute silk to a more sophisticated extraction process using solvents. Chain worked out a series of steps to isolate, purify and concentrate the penicillin in the liquid but another member of the team improved the process so that soon they were able to extract and produce penicillin as a brown powder in small but useful quantities.
Now the team could experiment with the powder to test its effects. Chain dissolved some in water and injected it into two mice that survived the experience despite its highly impure state. Working with increasing strengths of the powder, Florey's team tested it on blood, hormones and living cells. The turning point came, however, one morning in May , when Florey injected a lethal dose of streptococcus pyogenes bacteria into eight mice but injected four of them with penicillin as well.
The team anxiously watched the mice and by the middle of that night - just 16 hours later - all the unprotected mice were dead while those that had received penicillin remained alive and well. Chain is said to have almost danced with glee and even the understated Florey gave way to excitement when he later called his assistant Margaret Jennings to report the outcome of the experiment and said: "It looks like a miracle".
The team duly reported to other scientists that penicillin was a therapeutic agent able to kill sensitive germs in a living body and, with so many people suffering war wounds, the race began to work out ways to make enough of the stuff to test it on people. Not until February was there sufficient funding to do that. A policeman named Albert Alexander, near death from an infection sustained when he pricked himself on a rose thorn, was selected as the first recipient of penicillin.
Within a day, Alexander was showing dramatic signs of recovery but there was no more penicillin available to give him further treatment. Despite heroic efforts to filter his urine to recapture any excreted penicillin, Alexander's infection took hold again and he died. It was later edited and republished in Nobel Lectures. To cite this document, always state the source as shown above. In he was created a Knight Bachelor.
Sir Howard Florey died on February 21, Back to top Back To Top Takes users back to the top of the page. Nobel Prizes Thirteen laureates were awarded a Nobel Prize in , for achievements that have conferred the greatest benefit to humankind. See them all presented here.
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