Abstract
Aflatoxin contamination of agricultural commodities continues to be a serious problem in the United States. Breeding for resistant genotypes has been unsuccessful and detoxification of food sources is not economically feasible. New strategies for control may become apparent once more is known about the biosynthesis and regulation of aflatoxin. Although the biosynthetic pathway of aflatoxin has been extensively studied, little is known about the regulation of the individual steps in the pathway. We have developed a genetic transformation system forAspergillus flavus that provides a new and expedient approach to studying the biosynthesis of aflatoxin and its regulation. Through the use of this genetic transformation system, genes for aflatoxin biosynthesis can be identified and isolated by the complementation of aflatoxin negative mutants. In this paper we discuss molecular strategies for studying the regulation and biosynthesis of aflatoxin.
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References
Anderson MS, Dutton MF. The use of cell free extracts derived from fungal protoplasts in the study of aflatoxin biosynthesis. Experientia 1978; 35: 21–22.
Anderson MS, Dutton MF. Biosynthesis of Versicolorin A. Appl Envir Microbiol 1980; 40: 706–709.
Andrianopoulos A, Hynes MJ. Cloning and analysis of the positively acting regulatory gene amdR fromAspergillus nidulans. Mol Cell Biol 1988; 8: 3532–3541.
Ballance DJ, Turner G. Development of a high-frequency transforming vector forAspergillus nidulans. Gene 1985; 36: 321–331.
Bhatnagar D, Ullah AHJ, Cleveland TE. Purification of a methyl transferase fromAspergillus parasiticus SRRC 163 involved in the aflatoxin biosynthetic pathway. Prep Biochem 1988; 18: 321–349.
Boeke JD, LaCroute F, Fink GR. A positive selection for mutants lacking orotidine-5′-phosphate decarboxylase activity in yeast: 5-fluoro-orotic acid resistance. Mol Gen Genet 1984; 197: 345–346.
Cantoral JM, Diez B, Barredo JL, Alvarez E, Martin JF. High-frequency transformation ofPenicillium chrysogenum. Bio/Tech 1987; 5: 494–497.
Davis ND, Iyer SK, Diener UL. Improved method of screening for aflatoxin with a coconut agar medium. Appl Envir Microbiol 1987; 53: 1593–1595.
Dutton MF. Enzymes and aflatoxin biosynthesis. Microbiol Rev 1988; 52: 274–295.
Dutton MF, Anderson MS. Role of Versicolorin A and its derivatives in aflatoxin biosynthesis. Appl Envir Microbiol 1982; 43: 548–551.
Henson JM, Blake NK, Pilgeram AL. Transformation ofGaeumanomyces graminis to benomyl resistance. Curr Genet 1988; 14: 113–117.
Holden DW, Wang J, Leong SA. DNA-mediated transformation ofUstilago hordei andUstilago nigra. Physiol Mol Plant Pathol 1988; 33: 235–239.
Jeenah MS, Dutton MF. The conversion of sterigmatocystin to O-methylsterigmatocystin and aflatoxin B1 by a cell-free preparation. Biochem Biophys Res Com 1983; 116: 1114–1118.
Mattern IE, Unkles S, Kinghorn JR, Pouwels PH, Van den Hondel CAMJJ. Transformation ofAspergillus oryzae using theA. niger pyrG gene. Mol Gen Genet 1987; 210: 460–461.
May GS, Gambini J, Weatherbee JA, Morris NR. Identification and functional analysis of Beta-tubulin genes by site specific integrative transformation inAspergillus nidulans. J Cell Biol 1985; 101: 712–719.
Meyerowitz EM, Guild GM, Prestidge LS, Hogness DS. A new cosmid vector and its use. Gene 1980; 11: 271.
Mullaney EJ, Punt PJ, Van den Hondel CAMJJ. DNA mediated transformation ofAspergillus ficuum. Appl Microbiol Biotechnol 1988; 28: 451–454.
Oakley BR, Rinehart JE, Mitchell BL, Oakley E, Carmona C, Gray GL, May GS. Cloning, mapping and molecular analysis of the pyrG (orotidine-5′-phosphate decarboxylase) gene ofAspergillus nidulans. Gene 1987; 61: 385–399.
Osmani SA, May GS, Morris NR. Regulation of the mRNA levels of nimA, a gene required for the G2-M transition inAspergillus nidulans. J Cell Biol 1987; 104: 1495–1504.
Papa KE. Linkage groups inAspergillus flavus. Mycologia 1976; 68: 159–165.
Papa KE. Genetics of aflatoxin production inAspergillus flavus: Linkage between a gene for a high B2∶B1 ratio and the histidine locus on linkage group VIII. Mycologia 1977; 69: 1185–1190.
Papa KE. Genetics ofAspergillus flavus: complementation and mapping of aflatoxin mutants. Genet Res 1979; 34: 1–9.
Papa KE. Dominant aflatoxin mutant ofAspergillus flavus. J Gen Microbiol 1980; 118: 279–282.
Papa KE. Genetics ofAspergillus flavus: linkage of aflatoxin in mutants. Can J Microbiol 1984; 30: 68–73.
Picknett TM, Saunders G, Ford P, Holt G. Development of a gene transfer system forPenicillium chrysogenum. Curr Genet 1987; 12: 449–455.
Raj HG, Viswanathan L, Murthy HSR, Venkitasubramanian TA. Biosynthesis of aflatoxin by cell-free preparations fromAspergillus flavus. Experientia 1969; 25: 1141–1142.
Singh R, Hsieh DPH. Enzymatic conversion of sterigmatocystin into aflatoxin B1 by cell-free extracts ofAspergillus parasiticus. Appl Envir Microbiol 1976; 31: 743–745.
Smith JE, Moss MO. Structure and formation of mycotoxins. In: Smith JE, Moss MO, eds. Mycotoxins: formation, analysis, and significance. Great Britain: John Wiley and Sons, Ltd, 1985: 31–49.
Timberlake WE, Boylan MT, Cooley MB, Mirabito PM, O'Hara EB, Willett CE. Rapid identification of mutationcomplementing restriction fragments fromAspergillus nidulans cosmids. Exp Mycology 1985; 9: 351–355.
Turgeon BG, Garber RC, Yoder OC. Development of a fungal transformation system based on selection of sequences with promoter activity. Mol Cell Biol 1987; 7: 3297–3305.
Turner G, Ballance DJ. Cloning and transformation inAspergillus. In: Bennett JW, Lasure LL, eds. Gene manipulations in fungi. Orlando, Florida: Academic Press, Inc., 1985: 259–278.
Van Hartingsveldt W, Mattern IE, Van Zeijl CMJ, Pouwels PH, Van Den Hondel CAMJJ. Development of a homologous transformation system forAspergillus niger based on the pyrG gene. Mol Gen Genet 1987; 206: 71–75.
Vollmer SJ, Yanofsky C. Efficient cloning of genes ofNeurospora crassa. Proc Natl Acad Sci USA 1986; 83: 4869–4873.
Wan NC, Hsieh DPH. Enzymatic formation of the bisfuran structure in aflatoxin biosynthesis. Appl Envir Microbiol 1980; 39: 109–112.
Woloshuk CP, Seip ER, Payne GA, Adkins CR. Genetic transformation system for the aflatoxin-producing fungusAspergillus flavus. Appl Envir Microbiol 1989; 55: 86–90.
Yelton MM, Hamer JE, Timberlake WE. Transformation ofAspergillus nidulans by using a trpC plasmid. Proc Natl Acad Sci USA 1984; 81: 1470–1474.
Yelton MM, Timberlake WE, Van Den Hondel CAMJJ. A cosmid for selecting genes by complementation inAspergillus nidulans: selection of the developmentally regulated yA locus. Proc Natl Acad Sci USA 1985; 82: 834–838.
Zamir LO, Hufford KD. Precursor recognition by kinetic pulse-labeling in a toxigenic aflatoxin B1-producing strain ofAspergillus. Appl Envir Microbiol 1981; 420: 168–173.
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Payne, G.A., Woloshuk, C.P. Transformation ofAspergillus flavus to study aflatoxin biosynthesis. Mycopathologia 107, 139–144 (1989). https://doi.org/10.1007/BF00707551
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DOI: https://doi.org/10.1007/BF00707551