|Dombrink Kurtzman, Mary Ann|
Submitted to: Antonie Van Leeuwenhoek
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 6, 2005
Publication Date: May 15, 2006
Citation: Dombrink Kurtzman, M. 2006. The isoepoxydon dehydrogenase gene of the patulin metabolic pathway differs for penicillium griseofulvum and penicillium expansum. Antonie Van Leeuwenhoek International Journal of General and Molecular Microbiology. 89:1-8. Interpretive Summary: Apple juice contains the mycotoxin patulin, which may represent a risk to human health. One of the genes for patulin production was sequenced in three different patulin producing molds, which are identified as Penicillium expansum, Penicillium griseofulvan and Penicillium clavigerum. Major differences were detected in the amino acid sequences of these species and these differences correlate with patulin production. These results should be of value to the apple industry for species detection and for reducing the fungal load in apple juice.
Technical Abstract: Purified DNA from isolates of Penicillium griseofulvum, P. expansum and P. clavigerum was used as a template to amplify an ca. 600-bp fragment of the isoepoxydon dehydrogenase (idh) gene. Primer pairs designed from the P. griseofulvum gene (GenBank AF 006680) to amplify specific regions of the idh gene yielded similar sized bands for all strains. Asymmetrical amplification produced DNA products for sequencing. DNA sequences were translated to produce the corresponding amino acid sequences. After removal of two introns present in the area sequenced, amino acid sequences were compared. Each of the amino acid sequences of P. griseofulvum strains was identical. There were eleven amino acid differences present in the P. expansum strains compared to strains of P. griseofulvum. The differences correlated with the amount of patulin, with strains of P. griseofulvum producing the greatest amounts of patulin, although P. expansum is the primary fungus responsible for contamination of fruits, mainly apples, resulting in production of patulin.