Parallels in Intercellular Communication in Oomycete and Fungal Pathogens of Plants and Humans
Figure 2
Sexual pheromone synthesis in Phytophthora and Mucoralean fungi.
In Phytophthora, A2 mating type cells produce α2 hormone from phytol. The α2 hormone must be transported into the A1 mating type cells to serve as a precursor of the α1 hormone (upper). In Mucoralean fungi, both mating type cells produce pheromone intermediates from β-carotene. The mating type unique intermediates then must be transported into the opposite mating type partners, where the synthesis of the mature mating pheromone, trisporic acid, is completed (bottom). Thus, in both microbes, pheromone synthesis cannot be completed without mating partners in close proximity. Furthermore, exchange of pheromone intermediates is a key characteristic shared in both evolutionarily distinct pathogens.