Characterization of a novel 8 R,11 S -linoleate diol synthase from Penicillium chrysogenum by identification of its enzymatic products

Abstract

To identify novel fatty acid diol synthases, putative candidate sequences from Penicillium species were analyzed, and hydroxy fatty acid production by crude Penicillium enzyme extracts was assessed. Penicillium chrysogenum was found to produce an unknown dihydroxy fatty acid, a candidate gene implicated in this production was cloned and expressed, and the expressed enzyme was purified. The product obtained by the reaction of the purified enzyme with linoleic acid was identified as 8 R ,11 S -dihydroxy-9,12( Z,Z )-octadecadienoic acid (8 R ,11 S -DiHODE). The catalytic efficiency of this enzyme toward linoleic acid was the highest among the unsaturated fatty acids tested, indicating that this enzyme was a novel 8 R ,11 S -linoleate diol synthase (8 R ,11 S -LDS). A sexual stage in the life cycle of P. chrysogenum has recently been discovered, and 8 R ,11 S -DiHODE produced by 8 R ,11 S -LDS may constitute a precocious sexual inducer factor, responsible for regulating the sexual and asexual cycles of this fungus.