Penicillin’s Unique Discovery
EACH time you take a breath, eat, drink, smell or touch something, your body’s defense mechanism goes to work to protect you from the possibility of harmful bacteria getting into your bloodstream. Millions of white cells floating in the bloodstream literally attack, swallow and digest any harmful invaders. But only in recent generations has the body’s marvelous hygienic patrol been clearly understood.
Previous to our century, infected operation wounds were the cause of many hospital deaths. It began to be realized that bacteria that gained entry at the incision made by the surgeon poisoned the bloodstream. Contaminated surgical equipment, clothing and unwashed hands became suspect. Lives were saved as sterilized equipment, hygienic methods and antiseptics became standard procedure in the operating process. Chemicals such as carbolic acid (phenol), lysol and iodine were used to stop the growth of bacteria. But such discoveries only brought partial success since the antiseptics would only stop the growth of bacteria outside the body.
The doctor’s greatest need, however, was to discover an internal antiseptic capable of destroying bacteria after they had established themselves within the body but without harming the patient. Could any such internal antiseptic be found?
The World of Microorganisms
A spoonful of fertile soil contains millions of bacteria and molds that keep multiplying. Among themselves there is a never-ending struggle for existence. Some fiercely aggressive bacteria, in order to kill their competitors, diffuse minute quantities of deadly poison. It is this poison that is called an antibiotic. Thus, when different poisons are isolated from different types of bacteria, a variety of antibiotics are obtained.
Suppose, for example, that certain bacteria invaded your body. Today it may be a relatively easy process to prescribe a particular antibiotic for your illness. But even as late as the 1920’s the idea of isolating a particular antibiotic from bacteria and injecting it into the bloodstream as a safe internal antiseptic was rejected by the British medical profession. It was generally thought that no substance existed that would attack bacteria cells without harming human cells at the same time. One doctor, however, persisted in thinking differently.
Scottish-born Alexander Fleming spent almost his entire life as a doctor in London, studying the problems of infection and the use of antiseptics. In 1922 he made a remarkable observation. He took a test tube containing water mixed with inoffensive bacteria that turned the water milky. To this he added just one human teardrop. In seconds the milky substance cleared! It was obvious that in human tears there must be a chemical capable of destroying bacteria with astonishing speed. He named it “lysozyme” because it could “lyse,” that is, dissolve, bacteria.
Lysozyme, however, proved disappointing as it was effective against harmless microbes but powerless against those causing disease. The discovery was highly beneficial, however, in that it pointed Fleming to a completely new principle in mankind’s struggle against disease—the destruction of bacteria by using a harmless chemical. It prepared him for a similar incident six years later.
Historic Moment of Discovery
In 1928 in his laboratory, in shallow glass dishes, Fleming was cultivating staphylococci, the bacteria that cause boils. An old friend named Pryce dropped in to see him. Something that was to mean the difference between life and death to multitudes was about to take place. While talking to Pryce, Fleming removed the lids from several of his cultures. Suddenly, he stopped talking. After observing one culture for a moment, he said in his usual unconcerned tone: “That’s funny . . .” On the culture there was a growth of mold as usual. But all around the mold, the colonies of staphylococci had been dissolved. Instead of forming opaque yellow masses, they looked like drops of dew.
Fleming concluded that something produced by the mold was diffusing the bacteria and dissolving them. Today we know that that something was penicillin, a drug that was to revolutionize medicine. The arrival of the right spore itself falling out of the air and into the right culture dish, may have been the accident of all accidents.
Next, Fleming grew some blue-green mold (similar to that which appears on oranges, stale bread, ripening cheese, decaying fruit) on the surface of a liquid meat broth. It absorbed nourishment and diffused its antibiotic. After several days it was filtered as a crude juice that Fleming then named penicillin.
In a test tube his mold juice would destroy gonorrhea, meningitis, diphtheria and pneumonia bacteria. And, most important, it was nonpoisonous to man! Fleming suggested to the medical profession that here might be the ideal antiseptic. His audiences responded with icy indifference. They felt strongly that when bacteria established themselves within the body, they were out of the reach of all chemicals.
Because Fleming and his assistants did not have the know-how to handle the chemistry problems associated with isolating and purifying penicillin, virtually nothing more was done in its development for more than eight years. It seemed penicillin was on the way to being forgotten.
In 1939, due mainly to the diseases soldiers were contracting on the battlefield, two scientists educated in medicine and chemistry, Howard Walter Florey and Ernst Boris Chain, joined together in England in an assignment to investigate bacteria antagonism. Their research led them to Fleming’s writings on lysozyme and penicillin. Soon, they were working with his mold juice and, after repeated failures, the elusive chemical was finally produced in stable powder form.
There was much excitement when four disease-infected mice were cured. Then, in 1941, the first human was treated successfully. As one scientist reported, “the response to penicillin was considered almost miraculous.” It was demonstrated that penicillin could be diluted 120 million times and still remain effective against bacteria. This was almost unbelievable!
Because of wartime problems, Florey, with his precious mold, transferred from England to Peoria, Illinois, U.S.A. Fleming’s mold was unsuitable for mass producing penicillin. After a very widespread search, Mary Hunt of Peoria, who assisted Dr. Kenneth B. Raper and who was given the title “Mouldy Mary,” found a suitable mold from a rotten cantaloupe. The descendants of its mold have since become the chief source of penicillin. Soon, penicillin was in full production in many countries, and Fleming, Florey and Chain were awarded the Nobel prize for medicine in 1945.
An Unsolved Mystery
“That’s funny!” was the exclamation used by Fleming in 1928 to indicate that what he saw on his culture plate was hard to account for. It does seem incredible that many attempts of numerous scientists, including Fleming himself, have never succeeded in getting the same thing to happen again! “Quite one of the luckiest accidents that has ever occurred in medicine,” commented Lord Florey. Thirty-six years later, Professor Ronald Hare, in an effort to solve the mystery, conducted an elaborate series of experiments and confirmed that what happened in Fleming’s laboratory must have been very exceptional.
In 1971 Sir Ernst Boris Chain summarized the then scientific view:
“The phenomenon which Fleming observed seems simple and straightforward enough but in actual fact it is not, and few people are aware of and understand its complexity and the fact that it needed the coincidence of several most unusual circumstances to make the observation possible.”
Others have expressed the view that Fleming misinterpreted and misunderstood what he saw on his laboratory plate and that it could not have happened in the way Fleming thought it did. If doubts are being expressed as to who actually discovered penicillin, when and how, the end result remains—a truly remarkable, life-saving drug available to medicine.
In nonsensitive persons penicillin has a good record of freedom from side effects but some susceptible persons are subject to skin rash or difficulty in breathing. A few individuals suffer a form of shock and some have died. It is not a cure-all. There are many common ailments on which it has no effect at all, including the common cold, since antibiotics have no effect on virus-caused infections. They are effective only against bacterial infections. But Science World, January 10, 1980, commented that many doctors give antibiotics just to “play it safe and prevent bacterial infection before it occurs.”
Because of its reputation, many naïve patients request penicillin because they believe it will bring immediate relief, and, regrettably, doctors too easily prescribe it. “I wouldn’t give penicillin without a culture,” advises Dr. James Smith, associate professor of internal medicine at the University of Texas Southwestern Medical School and chief of infectious diseases at the Dallas Veterans Administration Hospital. Health authorities warn that from the point of view of the population as a whole the widespread and unnecessary use of penicillin is most undesirable because it encourages the emergence and spread of bacteria formerly destroyed by but now resistant to penicillin. “If antibiotic use continues being abused we are going to pay a toll,” comments Dr. Stanley Falkow, professor of microbiology and medicine at the University of Washington. “We cannot be certain that we are always going to have the appropriate alternative drug available,” he said, when commenting on a number of super-germs that are now resistant to antibiotics. Some medical men prescribe it strictly only when necessary—and that is not often. In some countries it is now considered to be one of the drugs of last resort. It should never be taken except on medical advice.
The immense strength of penicillin in destroying the bacteria responsible for numerous life-threatening infections, combined with its ability to do so without interfering with the body’s defense mechanism, makes it one of today’s wonder drugs. Precisely how mankind stumbled across it was unique. No one really knows!