title: Cloning of a gene associated with aflatoxin B1 biosynthesis in Aspergillus parasiticus.
abstract: A cosmid library was constructed by inserting genomic DNA isolated from a wild-type aflatoxin-producing strain of Aspergillus parasiticus (SU-1) into a cosmid vector containing an homologous nitrate reductase (niaD) gene as a selectable marker. One cosmid was isolated which complemented an aflatoxin-deficient, nitrate-nonutilizing mutant strain, A. parasiticus B62 (nor-1, niaD), to aflatoxin production. Deletion and complementation analyses showed that a 1.7 kb BglII-SphI DNA fragment isolated from this cosmid was responsible for renewed aflatoxin production. Northern hybridization analyses revealed that the major RNA transcribed from this DNA fragment was 1.4 kilonucleotides in size. Genetic complementation proved to be a useful strategy for cloning a gene associated with aflatoxin biosynthesis in A. parasiticus.
authors.affiliation: Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824.
authors.forename: P K
authors.initials: PK
authors.lastname: Chang
authors.forename: C D
authors.initials: CD
authors.lastname: Skory
authors.forename: J E
authors.initials: JE
authors.lastname: Linz
mesh_terms: D016604:Aflatoxin B1 / Q000096:biosynthesis*; D001230:Aspergillus / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D003360:Cosmids; D005800:Genes, Fungal / Q000235:genetics*; D005816:Genetic Complementation Test; D009154:Mutation; D014158:Transcription, Genetic
chemical_list: D016604:Aflatoxin B1