Characterization of Ricin and R. communis Agglutinin Reference Materials

Ricinus communis intoxications have been known for centuries and were attributed to the toxic protein ricin. On the basis of its availability, toxicity, ease of preparation and the current lack of medical countermeasures ricin gained attention as potential biological warfare agent. While different technologies for ricin analysis have been established, hardly any universally agreed “gold standards” are available. Expert laboratories currently use differently purified in-house materials, making any comparison of accuracy and sensitivity of different methods nearly impossible. Technically challenging is the discrimination of ricin as threat agent from R. communis agglutinin (RCA120), a less toxic, but highly homologous protein also contained in Ricinus communis. Here, we established both highly pure ricin and RCA120 reference materials which were extensively characterized by capillary gel electrophoresis, SDS-PAGE, LC-ESI MS and MALDI TOF approaches as well as immunological and functional techniques. The purity reached >97% for ricin and >99% for RCA120. Different isoforms of ricin as well as RCA120 were unambiguously identified and distinguished by LC-ESI MS/MS. In terms of function, a real-time cytotoxicity assay showed that ricin is approximately 300-fold more toxic than RCA120. The highly pure ricin and RCA120 reference materials were used to conduct an international proficiency test.

WORBS Sylvia;  SKIBA M;  SÖDERSTRÖM Martin;  RAPINOJA Marja-Leena;  ZELENY Reinhard;  RUSSMANN Heiko;  SCHIMMEL Heinz;  VANNINEN Paula;  FREDRIKSSON Sten-Åke;  DORNER Brigitte; 

2015-12-01

MDPI AG

JRC97502

2072-6651,   

https://www.mdpi.com/2072-6651/7/12/4856,    https://publications.jrc.ec.europa.eu/repository/handle/JRC97502,   

10.3390/toxins7124856,