ISSN:
1365-3059
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Production of the solanapyrone toxins by Ascochyta rabiei is nutrient dependent. When grown on a medium consisting entirely of expressed sap from the aerial parts of young chickpea plants (PSM). only low concentrations of the solanapyrones were produced (〈 24 μM). However, toxicity of 4-day-old culture filtrates to isolated cells of chickpea leaflets was comparable with that obtained from 12-day-oId culture filtrates on Czapek Dox nutrients supplemented with chickpea seed extract or cations—media that are conducive to solanapyrone production. The additional toxic component which peaked at 4 days in culture was heat labile, losing about 50% of its activity on boiling for 10 min. Affinity for solid-phase extraction media, precipitation with ammonium sulphate and acetone, ionization properties and UV absorption characteristics suggested that the toxin was a polypeptide. The toxin was purified by solid-phase extraction, acetone precipitation and high performance liquid chromatography (HPLC) on a C2 column. Hydrolysis of the purified toxin yielded 14 amino acids, and calculation of the numbers of residues of each amino acid suggested a molecular mass of 7, 551 Da, A band corresponding to this molecular mass was present on SDS-PAGE gels. However, both the native peptide and its hydrolysate contained a compound that reacted with p-anisaldehyde suggesting the possibility of a glycosidic moiety.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-3059.1994.tb02691.x
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