title: Molecular characterization of ochratoxin A producing strains of the genus Penicillium.
abstract: Sixty-six strains classified as P. verrucosum based on morphological criteria were characterized by molecular methods like RAPD, AFLP and ITS sequencing. Two groups could be identified by RAPD and AFLP analyses. The two RAPD as well as the two AFLP groups were completely coincidental. Strains in the two groups differed in their ability to produce ochratoxin A, with group I containing mainly high producing strains, and group II containing moderate to non-producing strains. The strains from group I originate from foods, such as cheeses and meat products, while the strains from group II originate from plants. The ribosomal ITS1-5.8S-ITS2 sequences were similar, except for two single nucleotide exchanges in several strains of each group. A chemotaxonomical analysis of some of the strains identified differences between the groups in secondary metabolite production. Strains from group I possessed the chemotype of P. nordicum and strains from group II that of P. verrucosum. The differences at the RAPD and AFLP level, which parallel the chemotypic differences, are consistent with the recent reclassification of ochratoxin A producing penicillia to be either P. verrucosum or P. nordicum. The homolgy between the ITS sequences however indicates phylogenetic relationship between the two species.
authors.affiliation: Dept. Sanitat i Anatomia Animals, Facultat de Veterinària, Universitat Autòmoma de Barcelona, Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Castella
authors.forename: Thomas Ostenfeld
authors.initials: TO
authors.lastname: Larsen
authors.forename: Javier
authors.initials: J
authors.lastname: Cabanes
authors.forename: Holger
authors.initials: H
authors.lastname: Schmidt
authors.forename: Alessandro
authors.initials: A
authors.lastname: Alboresi
authors.forename: Ludwig
authors.initials: L
authors.lastname: Niessen
authors.forename: Paul
authors.initials: P
authors.lastname: Färber
authors.forename: Rolf
authors.initials: R
authors.lastname: Geisen
mesh_terms: D001483:Base Sequence; D002953:Citrinin / Q000032:analysis; D017931:DNA Primers; D021903:DNA, Ribosomal Spacer / Q000032:analysis; D014644:Genetic Variation; D008969:Molecular Sequence Data; D009793:Ochratoxins / Q000032:analysis / Q000096:biosynthesis*; D010407:Penicillium / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods; D016415:Sequence Alignment
chemical_list: D017931:DNA Primers; D021903:DNA, Ribosomal Spacer; D009793:Ochratoxins; C025589:ochratoxin A; D002953:Citrinin