THE MIRACULOUS MOULD

See Also: HOSPITALS St Mary's Hospital; PHARMACEUTICALS; THE SECOND WORLD WAR The Scientists

Alexander Fleming was a medical researcher who worked in St Mary's Hospital in Paddington. In 1921 he discovered lysozyme, an anti-bacterial substance that is produced within people, animals, and plants. Seven years later, in a small laboratory that overlooked Praed Street, he discovered the mould Penicillium notatum. The following year he published a scientific paper about its properties.

The Australian-born scientist Howard Florey led a multi-disciplinary team that was assembled at the University of Oxford's Sir William Dunn School of Pathology. Ernst Chain was a member of the group. In 1938 he had an important breakthrough with lysozyme. This prompted his colleagues to scour the scientific literature for other naturally produced antibiotics. The search yielded Fleming's 1929 paper. In September 1939 the biochemist Norman Heatley was assigned the task of cultivating penicillin. The War Office agreed to fund the Florey team on condition that the scientist devoted a third of his time to working on poison gas research.

In March 1940 Heatley appreciated that, by transferring the mould back and forth between acidic and alkaline solutions, the overall amount that was grown might be considerably boosted. He used his wide range of practical, non-scientific skills to build an automated extraction apparatus. Two months later penicillin was administered to some mice that had been infected with streptococci bacteria. The rodents were cured. The treatment's efficacy was demonstrated.

British pharmaceutical companies were unwilling to take on the production of penicillin. It was unproven and it would divert resources away from war-related work. In 1941 Florey and Heatley travelled to the United States. They offered their technology in exchange for volumes of the anti-bacterial agent that would enable clinical trials to be conducted. Subsequently, researchers working for Pfizer devised a technique that enabled penicillin to be grown in three dimensions rather than just on dishes. By 1944 the antibiotic was widely available.

The Florey group had not finished its development programme when information of penicillin's potential reached the physician Lord Moran, who was associated with St Mary's Hospital. His lordship s patients included Winston Churchill, the newspaper tycoon Lord Beaverbrook, and Lord McGowan of the chemicals company I.C.I.. The peer cultivated the media, whereas Florey refused to pander to it. This is why penicillin was to be popularly associated with Fleming rather than with the Australian. The 1945 Nobel Prize for medicine was awarded jointly to them both and Chain.

Location: St Mary's Hospital, Praed Street, W2 1NY (red, turquoise)

Website: www.imperial.nhs.uk/about-us/who-we-are/fleming-museum

David Backhouse 2024