Impact of Endofungal Bacteria on Infection Biology, Food Safety, and Drug Development

The filamentous mould Rhizopus microsporus is a member of the zygomycetes (lower fungi). While some strains serve as food fermenting fungi, others represent infamous plant pathogens and opportunistic human pathogens. Recently, it was shown that some strains of R. microsporus are associated with symbiotic bacteria. Here, we outline why these organisms are important for human health and how they can be exploited for drug development. Furthermore, we illustrate what the investigation of bacterial–fungal symbiosis can teach us about the evolution of pathogenicity factors in general.