title: Relationship between fumonisin production and FUM gene expression in Fusarium verticillioides under different environmental conditions.
abstract: Fusarium verticillioides is the main source of fumonisins, a group of mycotoxins that can contaminate maize-based food and feed and cause diseases in humans and animals. The study of the effect of different environmental conditions on toxin production should provide information that can be used to develop strategies to minimize the risk. This study analysed the effect of temperature (15°C-35°C), water activity (a(w): 0.999-0.93), salinity (0-125 g l(-1) NaCl) and pH (5-8) on the growth and production of fumonisins B(1) (FB1), B(2) (FB2) and B(3) (FB3) and the expression of FUM1 and FUM21 in F. verticillioides. The highest growth rate was measured at 25°C, a(w) of 0.998-0.99 and 0-25 g l(-1) of NaCl. Optimal conditions for fumonisin production were 30°C, a(w) of 0.99, 25 g l(-1) of NaCl and pH 5; nevertheless, the strain showed a good adaptability and was able to produce moderate levels of fumonisins under a wide range of conditions. Gene expression mirrored fumonisin production profile under all conditions with the exception of temperature: FUM1 and FUM21 expression was highest at 15°C, while maximum fumonisin production was at 30°C. These data indicate that a post-transcriptional regulation mechanism could account for the different optimal temperatures for FUM gene expression and fumonisin production.
authors.affiliation: Institute of Sciences of Food Production, CNR, Bari, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Fanelli
authors.forename: Anita
authors.initials: A
authors.lastname: Iversen
authors.forename: Antonio F
authors.initials: AF
authors.lastname: Logrieco
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Mulè
mesh_terms: D000818:Animals; D004777:Environment; D005506:Food Contamination; D037341:Fumonisins / Q000378:metabolism*; D005670:Fusarium / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D015870:Gene Expression; D005800:Genes, Fungal; D006801:Humans; D005810:Multigene Family; D009183:Mycotoxins / Q000096:biosynthesis* / Q000235:genetics*; D003313:Zea mays / Q000737:chemistry / Q000382:microbiology
chemical_list: D037341:Fumonisins; D009183:Mycotoxins; C056934:fumonisin B2; C073063:fumonisin B3; C056933:fumonisin B1