Clustered genes involved in cyclopiazonic acid production are next to the aflatoxin biosynthesis gene cluster in Aspergillus flavus.
Cyclopiazonic acid (CPA), an indole-tetramic acid mycotoxin, is produced by many species of Aspergillus and Penicillium. In addition to CPA Aspergillus flavus produces polyketide-derived carcinogenic aflatoxins. Aflatoxin biosynthesis genes form a gene cluster in a subtelomeric region. Isolates of A. flavus lacking aflatoxin production due to the loss of the entire aflatoxin gene cluster and portions of the subtelomeric region are often unable to produce CPA, which suggests a physical link of genes involved in CPA biosynthesis to the aflatoxin gene cluster. Examining the subtelomeric region in A. flavus isolates of different chemotypes revealed a region possibly associated with CPA production. Disruption of three of the four genes present in this region predicted to encode a monoamine oxidase, a dimethylallyl tryptophan synthase, and a hybrid polyketide non-ribosomal peptide synthase abolished CPA production in an aflatoxigenic A. flavus strain. Therefore, some of the CPA biosynthesis genes are organized in a mini-gene cluster that is next to the aflatoxin gene cluster in A. flavus.
Chang
Perng-Kuang
PK
Southern Regional Research Center, Agricultural Research Service, US Department of Agriculture, 1100 Robert E. Lee Boulevard, New Orleans, LA 70124, USA. perngkuang.chang@ars.usda.gov
Horn
Bruce W
BW
Dorner
Joe W
JW
D000348:Aflatoxins / Q000096:biosynthesis* / Q000235:genetics; D019883:Alkyl and Aryl Transferases / Q000235:genetics / Q000378:metabolism; D001231:Aspergillus flavus / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D007211:Indoles / Q000378:metabolism*; D008995:Monoamine Oxidase / Q000235:genetics / Q000378:metabolism; D005810:Multigene Family; D009183:Mycotoxins / Q000235:genetics / Q000378:metabolism*; D010453:Peptide Synthases / Q000235:genetics / Q000378:metabolism; D012988:Soil Microbiology
D000348:Aflatoxins; D005656:Fungal Proteins; D007211:Indoles; D009183:Mycotoxins; D008995:Monoamine Oxidase; D019883:Alkyl and Aryl Transferases; C032409:tryptophan dimethylallyltransferase; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase; C000543:cyclopiazonic acid