PASSAGE 4
Questions 31-40

Pénicillium chrysogenum, or Pénicillium notatum is a common mold – a fungus that has multicellular arms or filaments called hyphae. It can be found living indoors on food. Its spores, units of asexual reproduction that can evolve into a new organism, and are a major cause of allergens in humans. In 1928, Scottish scientist Alexander Fleming discovered that Pénicillium notatum contained a bacteria-killing antibiotic that he named penicillin.

Alexander Fleming was born in 1881 in Scotland. At the age of twenty, he entered St. Mary’s Hospital in London and studied medicine, then went on to become the assistant bacteriologist to Sir Almroth Wright, a pioneer in immunology and vaccine therapy. During World War I, Fleming served as a captain in the Royal Army Medical Corps and worked on the frontlines where he witnessed firsthand soldiers dying of sepsis. Sepsis, or systematic inflammatory response (SIRS), is blood poisoning due to the presence of bacteria in the blood. Fleming witnessed widespread sepsis, most of which was caused by infected wounds. Antiseptics were widely available yet Fleming believed they killed only surface bacteria while failing to eradicate deeper bacteria. After the war, Fleming was determined to find a cure for sepsis. In 1928, while researching the properties of staphylococci, a genus of gram-positive bacteria, he stumbled upon Pénicillium notatum.

By 1928, Fleming was regarded as a brilliant researcher whose laboratory was, more often than not, a mess. That same year, returning to his lab after an August holiday, he discovered that his staphylococci cultures had been contaminated by a fungus. Fleming was intent on throwing the cultures out when he noticed that the staphylococci colonies had been surrounded by an invading blue-green mold. Much to Fleming’s surprise, the invading mold had eradicated the staphylococci it had surrounded; whereas, those colonies of staphylococci that had not been touched by the mold were still thriving. He set about isolating and growing the mold which produced a substance that killed not only staphylococci, but also a number of other disease-causing bacteria, such as pneumonia, scarlet fever, meningitis and diphtheria. He called the bacteria-killing substance “mold juice.” Once he’d established that the mold was in fact part of the genus pénicillium, he called it penicillin.

In 1929, Fleming published the results of his experiments in the British Journal of Experimental Pathology. Yet despite such initial promise, his work garnered little attention, for growing pénicillium was difficult while extracting the antibiotic agent, the bacteria-killing penicillin itself, was even harder. These results, combined with tests proving that penicillin worked slowly, convinced Fleming that penicillin had no commercial appeal. By 1939, Fleming, having labored long and hard over penicillin, finally turned his attention to other matters. Then, in that same year, the Australian scientist Howard Walter Florey, director of the Sir William Dunn School of Pathology at Oxford University, read Fleming’s paper in which he described the anti-bacterial effects of pénicillium. Florey immediately saw the potential of pénicillium and, with the help of Ernst Chain, did more research on the effects of penicillin and produced it on a large scale successfully in the US. By 1943, frontline soldiers with infections were being treated with a new wonder drug called penicillin.

Câu 11: What is the passage mainly about?