... Fleming seemed doubtful at first, but he trusted his friends. He thought that if he did not like working in the laboratories, he could continue his path to becoming a surgeon. Fleming enjoyed the laboratory research, and this change in his career path would completely alter his life forever. In 1906, Fleming and Wright formerly began working together , and together they joined the Royal Army Medical Corps during World War One . Fleming was not a great World War One hero. However, this is not what made Fleming famous. All of medical science today knows Fleming to be the discoverer of one of the world's greatest medical breakthroughs: Penicillin, the ancestor to all antibiotics. It all began with one simple enzyme. In 1921, Fleming discovered that in a culture containing gram-positive cocci and a particular enzyme, all the cocci surrounding the enzyme was cleared, and that it could be found in all animal tissues and mucus. It then would make a cloudy liquid containing this enzyme clear. Of course, the way that Fleming first found this was by means of his own tears and nasal mucus, for Fleming had gotten some of his nasal mucus into the culture . Fleming brought this discovery to his colleagues, who were equally amazed, and it was Wright who helped Fleming name it micrococcus lysodeikticus (also known as the lysozyme). ...