Fungal-fungal cocultivation alters secondary metabolites of marine fungi mediated by reactive oxygen species (ROS)

Marine fungi are an important source of natural products, and many marine-derived secondary metabolites have been found to exhibit significant bioactivities, including antibacterial, antiviral, and anticancer properties. Cocultivation is a simple and effective method for discovering bioactive compounds. However, whether marine-derived and terrestrial-derived microorganisms exhibit differential response mechanisms under co-culture conditions remains unexplored. Our study details how cocultivation of marine fungi triggers the activation of biosynthetic gene clusters (BGCs) and leads to an increase in active secondary metabolites (SMs), which may contribute to the future development of antibiotics or anticancer drugs. Furthermore, our findings reveal that reactive oxygen species (ROS) function as specific signaling molecules in marine fungal-fungal interactions, offering novel insights into the evolutionary strategies of fungi in marine ecosystems.