How did Louis Pasteur create penicillin?

Louis Pasteur did not create penicillin; that achievement is attributed to Alexander Fleming, who discovered it in 1928. Pasteur is renowned for his work in microbiology and vaccination, particularly his development of the germ theory of disease and vaccines for rabies and anthrax. His contributions laid the groundwork for understanding Infectious Diseases, which later facilitated the identification and use of antibiotics like penicillin.