AIMS The objective of this study was to determine if acetosyringone affected the expression of aflatoxin biosynthetic genes. METHODS AND RESULTS Two genes, nor1 and ver1, representing genes whose products are involved in early and late steps in aflatoxin biosynthesis, were examined. Two GUS (beta-glucuronidase) reporter constructs, nor1:GUS (pGAP12) and ver1:GUS (pGAP13), were used to study t...

Aflatoxin biosynthesis in the filamentous fungus Aspergillus parasiticus involves a minimum of 21 enzymes, encoded by genes located in a 70 kb gene cluster. For aflatoxin biosynthesis to be completed, the required enzymes must be transported to specialized early and late endosomes called aflatoxisomes. Of particular significance, seven aflatoxin biosynthetic enzymes are P450/monooxygenases whic...

the inhibitory activities of aqueous and solvent extracts of twelve selected medicinal plants were evaluated against biosynthesis of aflatoxin b1 (afb1) by aspergillus flavus. the a. flavus was isolated from maize, and aflatoxin b1 biosynthesis was confirmed by comparison with standard afb1 using tlc method. in vivo antiaflatoxigenic efficacies of activity guided solvent extracts were determine...

The PT-domain of Polyketide synthase A (PksA) is crucial product template that controls the aldol cyclization and aromatization to create polyketide precursor. precursor leads biosynthesis of aflatoxin secondary metabolites. Being carcinogenic in nature these metabolic, efforts have been made explore novel inhibitors targeting PksA. Previously, [6]-gingerol reported as a prospective inhibitor f...

The mycotoxin aflatoxin is a secondary metabolite and potent human carcinogen. We investigated one mechanism that links stress response with coordinate activation of genes involved in aflatoxin biosynthesis in Aspergillus parasiticus. Electrophoretic mobility shift assays demonstrated that AtfB, a basic leucine zipper (bZIP) transcription factor, is a master co-regulator that binds promoters of...

The aflR gene from Aspergillus parasiticus and Aspergillus flavus may be involved in the regulation of aflatoxin biosynthesis. The aflR gene product, AFLR, possesses a GAL4-type binuclear zinc finger DNA-binding domain. A transformant, SU1-N3 (pHSP), containing an additional copy of aflR, showed increased transcription of aflR and the aflatoxin pathway structural genes, nor-1, ver-1, and omt-1,...

BACKGROUND AND OBJECTIVES Food contamination by aflatoxins is an important food safety concern for agricultural products. In order to identify and develop novel antifungal agents, several plant extracts and isolated compounds have been evaluated for their bioactivities. Anti-infectious activity of Piper betle used in traditional medicine of Malaysia has been reported previously. MATERIALS AND...

Background and Purpose: Aflatoxins are naturally produced by some species of Aspergillus, such as A. flavus and A. parasiticus. Aflatoxins reportedly have carcinogenic effects on human, poultry, and livestock, and therefore could be linked to severe human illnesses. Aflatoxin biosynthesis pathway involves different clustered genes, including structural, regular, and unassigned genes. The presen...

The enzymology of secondary metabolism has not received the same attention as that for primary (general) metabolism. There are traditional and other reasons for this bias, some of which will become apparent in this review. With the advent of recombinant deoxyribonucleic acid technology (genetic engineering), it seems inevitable that this state of affairs should change. Many secondary metabolite...

Biosynthesis of the highly toxic and carcinogenic aflatoxins in select Aspergillus species from the common intermediate O-methylsterigmatocystin has been postulated to require only the cytochrome P450 monooxygenase, OrdA (AflQ). We now provide evidence that the aryl alcohol dehydrogenase NorA (AflE) encoded by the aflatoxin biosynthetic gene cluster in Aspergillus flavus affects the accumulatio...