Fusarium Secondary Metabolism Biosynthetic Pathways: So Close but So Far Away

Abstract

Fusarium species are casual filamentous fungi, including opportunistic pathogens infecting plants worldwide, but also able to grow as saprotrophs in a range of climatic zones. The genus is extremely variable in terms of genetics, biology, ecology, and, consequently, secondary metabolism, which directly relates to ecological conditions and niches occupied by individual species. Fungal secondary metabolites are the main “weapon” of the pathogenic species before, during, and after the infection process, allowing for the communication with the organism that is being attacked. Many of secondary metabolites are common for diverse fungal microorganisms, and their mode of action is similar for various plant-pathogen systems. Fusaria are able to produce a range of quite specific metabolites, some of which have yet unknown biological functions. Nevertheless, genetic and biochemical pathways responsible for their biosynthesis remain under strong selection pressure, which keeps their structures and functions relatively stable, regardless of the producing organism. Here, we summarize the data available in recent literature reports on genetic and biochemical diversity occurring in the studies of main secondary metabolites produced by Fusarium species differing in origin and ecology.