Characterization of the function of the ver-1A and ver-1B genes, involved in aflatoxin biosynthesis in Aspergillus parasiticus

Aspergillus parasiticus SU-1 has two ver-1 genes, ver-1A and ver-1B, of which only ver-1A is functional during aflatoxin (AF) biosynthesis. The gene product of ver-1A is associated with the conversion of versicolorin A into sterigmatocystin in AFB(sub 1) biosynthesis. A linearized plasmid used to disrupt the ver-1A and ver-1B gene by gene replacement disrupts only the ver-1A gene. The aflR gene, located in a duplicated chromosomal region upstream from ver-1A and ver-1B, also regulates AFB(sub 1) synthesis.