Penicillium chrysogenum

Penicillium chrysogenum, formerly known as Penicillium notatum, is a species of fungus in the genus Penicillium that grows in temperate and subtropical regions, appearing on salted foods and, more commonly, in damp or water-damaged indoor environments. It belongs to a species complex that also includes P. meleagrinum and P. cyaneofulvum, and molecular research has since shown that Alexander Fleming's original penicillin-producing mold actually belonged to a distinct species, P. rubens, rather than to P. notatum. The fungus rarely causes human disease but is economically important as the primary industrial source of beta-lactam antibiotics, especially penicillin, and it also produces other secondary metabolites such as roquefortine C, meleagrin, and fungisporin.