The Aflatoxigenic Aspergillus SPP

Silencing of the Aflatoxin Gene Cluster in a Diploid Strain of Aspergillus flavus Is Suppressed by Ectopic aflR Expression

“…This scaffold, together with scaffold 1047283863270, represents chromosome III. Cosmid 1911-A was shown to complement the arg-7 mutation in strain 796 (ATCC 60042) (Bennett and Papa 1988;Foutz et al 1995). The genomic position of arg-7 was located on scaffold 1047283863273 $1 Mb away from the aflatoxin gene cluster.…”

Molecular biology of aflatoxin biosynthesis

“…Parasexual analysis of eight aflatoxin blocked mutants in A. javzrs suggested that they were all genetically linked to markers on linkage group VII (Papa, 1984). However, attempts to demonstrate linkage of nor-7 and ver-7 by parasexual analyses have been confusing because of problems inherent in analysing ploidy levels of segregants and the nonrandom segregation of certain genes during haploidization (reviewed by Bennett & Papa, 1988).…”

“…As a testimony to their importance, aflatoxins have been the subject of numerous reviews in the past few years covering ecology , occurrence (Jelinek et al, 1989), detection (Pestka, 1986, l988), effects on human health (toxicity, carcinogenicity) (Bray & Ryan, 1991 ;Chang e t al., 1994;Chu, 1991 ; Dvorackova, 1990;Eaton & Gallagher, 1994), genetics (Bennett & Papa, 1988), biosynthesis Dutton, 1988) and compounds which affect biosynthesis , and control of aflatoxin contamination (Park e t al., 1988;Park & Liang, 1993;Bhatnagar e t al., 1995); (for general reviews see CAST, 1989;Ellis et al, 1991). Because of the difficulty in effectively and economically controlling aflatoxin contamination of food and feed by traditional agricultural methods (see below), recent efforts in several laboratories have focused on developing an indepth understanding of the molecular biology of the aflatoxin biosynthetic pathway.…”

“…Since the aspergilli include opportunistic pathogens of mammals, insects and plants, furthering our understanding of the regulation of gene expression, development and secondary metabolism in this diverse genus may provide important clues into their ecology and biology, leading not only to effective control of aflatoxin but also to more general means for control of this entire group of pathogens. & Papa, 1988). Bioconversion experiments using these aflatoxin blocked mutants, metabolic inhibitors and stable isotope-or radioisotope-labelled precursors or pathway intermediates have generated our current understanding of the order and mechanism of reactions in this complex biosynthetic pathway, which involves approximately 17 different enzymes (reviewed in Bhatnagar e t al., 1992; Dutton, 1988).…”

Two novel aflatoxin-producing Aspergillus species from Argentinean peanuts

“…Like A. pseudotamarii and 'A. flavus' NRRL 3251, A. flavus has later been reported to produce only B-type aflatoxins (Dorner et al, 1984;Klich & Pitt, 1985;Bennett & Papa, 1988;Ito et al, 2001;Ehrlich et al, 2004;Frisvad et al, 2005), while A. parasiticus, A. toxicarius, A. nomius and A. bombycis can produce both B-and G-type aflatoxins (Ehrlich et al, 2004;Frisvad et al, 2005 (Codner et al, 1963;Hesseltine et al, 1970;Cotty & Cardwell, 1999). Many aflatoxin B-and G-producing strains have been reported to produce small sclerotia, but they do not obviously belong to A. parvisclerotigenus (Saito & Tsurota, 1993;Cotty & Cardwell, 1999;Bayman & Cotty, 1993;Egel et al, 1994;Frisvad et al, 2005).…”