Enzyme reactions and genes in aflatoxin biosynthesis.
Aflatoxins are highly toxic and carcinogenic substances mainly produced by Aspergillus flavus and Aspergillus parasiticus. Sterigmatocystin is a penultimate precursor of aflatoxins and also a toxic and carcinogenic substance produced by many species, including Aspergillus nidulans. Recently, the majority of the enzyme reactions involved in aflatoxin/sterigmatocystin biosynthesis have been clarified, and the genes encoding the enzymes have been isolated. Most of the genes constitute a large gene cluster in the fungal genome, and their expression is mostly regulated by a product of the regulatory gene aflR. This review will summarize the enzymatic steps and the genes in aflatoxin/sterigmatocystin biosynthesis.
Yabe
K
K
National Food Research Institute, Tsukuba, 305-8642 Ibaraki, Japan. yabek@nfri.affrc.go.jp
Nakajima
H
H
D000105:Acetyl Coenzyme A / Q000235:genetics / Q000378:metabolism; D000348:Aflatoxins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D000880:Anthraquinones / Q000737:chemistry / Q000378:metabolism; D001230:Aspergillus / Q000201:enzymology / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000378:metabolism; D005656:Fungal Proteins / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D019746:Intramolecular Oxidoreductases / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D005810:Multigene Family; D013241:Sterigmatocystin / Q000096:biosynthesis; D014157:Transcription Factors / Q000378:metabolism
C113837:AFLR protein, Aspergillus; D000348:Aflatoxins; D000880:Anthraquinones; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D014157:Transcription Factors; D013241:Sterigmatocystin; D000105:Acetyl Coenzyme A; C029856:averufin; D019746:Intramolecular Oxidoreductases; C481650:5'-oxoaverantin cyclase