Biosynthetic gene clusters for epipolythiodioxopiperazines in filamentous fungi

Epipolythiodioxopiperazines (ETPs) are toxic secondary metabolites made only by fungi. Recent research efforts have provided insight into the molecular mechanisms of the toxicity of these compounds. The availability of complete genome sequences for many fungi has also facilitated the identification of putative ETP biosynthetic gene clusters. Expression and mutational analyses have confirmed the role of such gene clusters in the biosynthesis of two ETPs, sirodesmin PL and gliotoxin. The creation of mutants unable to produce these ETPs has facilitated the assessment of these molecules as virulence factors in interactions between pathogenic fungi and their hosts.