The Mycotoxin Threat to Food Safety

This workshop entitled “Mycotoxins from the Field to the Table” held in Omaha, Nebraska, USA from 29 November to 1 December, 2006 evolved from the OECD (Organization for Economic Co-operation and Development) Co-operative Research Program on “Biological Resource Management” that was initiated in 1979. It currently focuses on three specific areas, namely the natural resources challenge, sustainability in practice, and the food chain. This workshop was organized under the sustainability and food chain themes. The Cooperative Research Program\u27s two major activities are promotion of expert exchanges by supporting postdoctoral fellowship awards up to 26 weeks in an OECD host laboratory and sponsoring or co-sponsoring workshops under the themes priority areas. Currently participating countries in the program are: Australia, Austria, Belgium, Canada, Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Japan, Korea, The Netherlands, New Zealand, Norway, Poland, Portugal, Slovak Republic, Spain, Sweden, Switzerland, United Kingdom and the United States of America. The program usually sponsors 6 to 8 expert workshops per year. All information related to this program can be located at the internet website of OECD (www.oecd.org/arg/prog/). Any further information can be obtained from the OECD, Mr. Carl-Christian Schmidt, Head of the Co-operative Research Program, Trade and Agriculture Directorate, 2, rue André Pascal, 75775 Paris Cedex 16, France (email: Carl-Christian. [email protected])

Synthesis of (-)-strand RNA from the 3' untranslated region of plant viral genomes expressed in transgenic plants upon infection with related viruses

International audienceWhen expressed in transgenic tobacco plants, transgene mRNA that includes the 3' untranslated region (3' UTR) of Lettuce mosaic virus served as template for synthesis of complementary (-)-strand RNA following an infection by Tobacco etch virus, Tobacco vein mottle virus or Pepper mottle virus, but not when infected with Cucumber mosaic virus. Deletion of the 3' UTR from the transgene abolished the synthesis of (-)-strand transcripts. Similar results were obtained in transgenic tobacco plants expressing mRNA that includes the RNA3 3' UTR of Cucumber mosaic virus when infected with Tomato aspermy virus. These results show that the viral RNA-dependent RNA polymerase of several potyviruses and Tomato aspermy virus have the ability to recognize heterologous 3' UTRs when included in transgene mRNAs, and to use them as transcription promoters

Thermometer ions for matrix-enhanced laser desorption/ionization internal energy calibration

This work describes a method to use relative fragmentation yields to characterize the internal energy distribution of ions produced by matrix-enhanced laser desorption/ionization mass spectrometry (MELDI-MS, see: Wright LG, Cooks RG, Wood KL. Biomed. Mass Spectrom. 1985; 12:153162). Assuming that the fragmentation proceeds statistically and that the collisions in the source lead to a Boltzmann-like distribution of the internal energy, a characteristic parameter, the effective temperature, is introduced to describe the internal energy distribution of the ions observed. The hypotheses, advantages and drawbacks of the implementation of the method that uses substituted benzylpyridinium salts as thermometer ions are discussed. Use is made of two matrices that produce no matrix cations in MELDI and are suitable for small cationic salts. The actual value of this effective temperature significantly depends on an accurate determination of the threshold dissociation energies and on the time spent in the source, in addition to the statistical hypothesis itself. The method could be applied to normalize spectra in order to compare results issued from different instruments