Billroth and Penicillium

Between 1868 and 1873, a surgeon, Theodor Billroth, performed experiments with cultures of bacteria and molds (which he believed to be two aspects of a single form of life) to investigate their role in "accidental wound diseases." Some of the cultures teemed with rounded microorganisms arranged in chains; Billroth chose to call them streptococci. He also noticed that occasionally, when Penicillium appeared in a culture, bacteria failed to grow; he suggested that Penicillum could have "modified the medium" so as to render it unsuitable for bacterial growth. This may well have been the first observation of the antibacterial effect of Penicillium. Similar experiments were performed by Joseph Lister, who noticed in 1871 that bacteria tended to kill the Penicillium, and by John Tyndall, who described in 1876 a "battle" that could be won by either party.