Accumulation and Biosynthesis of Solanapyrone Phytotoxins by Ascochyta rabiei
نویسندگان
چکیده
The biosynthesis of the phytotoxins solanapyrone A , B and C produced by the phytopathogenic fungus Ascochyta rabiei has been investigated. To optimize feeding conditons for the tracer experiments the growth of the fungus and the accumulation of the toxins in submers culture were determined. The accumulation kinetics revealed that formation of the toxins occurs in the stationary phase of the growth indicating that synthesis of solanapyrones follows a typical pattern of secondary metabolism. Incorporation experiments with sodium [1-14C]and [2-13C]acetate were performed and the NMR-spectroscopically determined labelling pattern of the 13C-enriched solanapyrone A compound confirmed that the carbon skeleton of this compound is formed via the polyketide pathway. The biosynthetic route to solana pyrone B is discussed.
منابع مشابه
rabiei, the causal agent of Ascochyta blight of chickpea (Cicer arietinum L.), and toxin production-by the wild type
Ascochyta rabiei is the causal agent of blight of chickpea, an important food legume crop for human populations in Developing Countries. All reliably identified isolates of the fungus produce toxins in culture, known as the solanapyrones, of which solanapyrone A is the most frequently found and also the most toxic. The principal aim of the project was to determine the role of this toxin in the ...
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