Cercosporin, a photo-activated, non-host-selective phytotoxin produced by many species of
the plant pathogenic fungus Cercospora, causes peroxidation of plant cell membranes by
generating reactive oxygen species and is an important virulence determinant. Here we
report a new gene, CTB3 that is involved in cercosporin biosynthesis in Cercospora
nicotianae. CTB3 is adjacent to a previously identified CTB1 encoding a polyketide synthase
which is also required for cercosporin production. CTB3 contains a putative O …