Naslov
YAP1-like gene modulates aflatoxin biosynthesis in Aspergillus parasiticus

Autori
Reverberi, Massimo ; Zjalic, Slaven ; Ricelli, Alessandra ; Punelli, Federico ; Fabbri, Anna A. ; Fanelli, Corrado

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Journal of Plant Pathology / - : Edizioni ETS, 2006, S24-S24

Skup
XIII Congresso Nazionale della Società Italiana di Patologia Vegetale

Mjesto i datum
Foggia, Italija, 12.09.2006. - 16.09.2006

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
aflatoxins; oxidative stress-related transcription factors; antioxidant enzymes; lipoperoxides

Sažetak
In Aspergillus parasiticus Speare, NRRL 2999, lipoperoxide promotes aflatoxin biosynthesis in media favouring and not favouring their biosynthesis (potato dextrose broth -PDB- and Czapek dox broth -CD-, respectively). To stimulate oxidative stress in CD, cumene hydroperoxide (CH, 1 mM), a lipoperoxidation inducer, was used. The two regioisomers of the hydroperoxides of linoleic acid (9-HODE and 13-HODE) were analysed in A. parasiticus mycelia by liquid chromatography-mass spectrometry (LC-MS). Some oxidative stress-related transcription factors such as yap1-like, skn7-like and hsf2- like appeared to drive, following their activation, the correlation between oxida- tive stress in the mycelia and aflatoxin biosynthesis. Expression of these factors led to the activation of defence responses of A. parasiticus cells such as antioxidant enzyme activities: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). In accordance with the role played by antioxidant machinery in the cell and toxin biosynthesis, the well-known antioxidants caffeic acid and BHA, were able to inhibit lipoperoxide formation and aflatoxin biosynthesis. The A. parasiticus mutant ∆yap1-like grown in an aflatoxin conducive medium (PDB) anticipated and increased aflatoxin biosynthesis in comparison to wild type and, at the same time, markedly inhibited SOD, CAT and GPX activity. Probably in ∆yap1-like strain the cell environment is more suitable to support earlier and higher toxin formation. Reactive species as lipoperoxides formed during fungal growth create a stressing environment in front of which fungal cell activates oxidative stress transcription factors and aflatoxin biosynthesis. Yap1-like appears to play a modulating role in metabolic events leading to aflatoxin biosynthesis in A. parasiticus.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Biotehnologija

POVEZANOST RADA