|Dombrink Kurtzman, Mary Ann|
Submitted to: International Union of Microbiological Societies Proceedings/Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: May 3, 2005
Publication Date: July 24, 2005
Citation: Dombrink Kurtzman, M. 2005. The isoepoxydon dehydrogenase gene of the patulin metabolic pathway differs for penicillium griseofulvum and penicillium expansum [abstract]. International Union of Microbiological Societies Proceedings/Abstracts. p.10. Technical Abstract: The major fungus associated with patulin production in apples and apple juice is Penicillium expansum, although the secondary metabolite patulin has been intensively studied in P. griseofulvum, a relatively common soil fungus capable of producing significant amounts of patulin in the soil. Purified DNA from isolates of Penicillium griseofulvum, P. expansum and P. clavigerum was used as a template to amplify an approximately 600-bp fragment of the isoepoxydon dehydrogenase (idh) gene. Primer pairs designed from P. griseofulvum (GenBank accession AF006680) amplified two different regions of the idh gene and 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 the two introns present in the regions sequenced. All P. griseofulvum strains had identical amino acid sequences for the idh gene. There was a difference of twelve amino acids in two of the P. expansum strains, compared to strains of P. griseofulvum. Threonine was substituted for lysine in a conserved coenzyme (NADP) binding area of the P. expansum strains. Strains of P. expansum had nine extra nucleotides in the first intron. Differences in amino acid sequence and intron length are likely to influence the ability of a particular strain to produce patulin and may be responsible for the greater amounts of patulin produced by P. griseofulvum.