Ricin purification

The discovery of ricin in the Senate in Washington in 2004, at a Paris railway station in 2003 plus the finding in Afghanistan by a journalist, of a description of ricin purification, demonstrate the reality of its perceived potential as a chemical weapon. The suitability of ricin for this purpose derives from its extreme toxicity to mammalian cells, the fact that the source is naturally... 

Due to the extraordinary toxicity of intact ribosome-inactivating toxins like ricin, abrin, and modeccin, purification and handling of these proteins must be done with extreme care. Even dust from crude seed powders or lyophilized proteins should be considered dangerous. During... 

Purification of the immunotoxin conjugate from unconjugated ricin can be done using a column of TSK3000 SW (Toya Soda, Japan) according to the method of Myers et al. (1989). 

Ishiguro, Masatsune, Takao Takahashi, Gunki Funatsu, Katsuya Hayashi, and Masaru Funatsu. "Biochemical Studies on Ricin. I. Purification of Ricin." Journal of Biochemistry (Tokyo, Japan) (1964) 587-92. 

Kabat, Elvin E., Michael Eleidelberger, and Ada E. Bezer. "A Study of the Purification and Properties of Ricin." Journal of Biological Chemistry 168 (1947) 629-39. 

Moriyama, Hideo. "Purification and Properties of Ricin." Igaku to Seibutsugaku (1947) 163-66. 

Commercially obtained preparations of ricin A chain and abrin A chain may require further purification to eliminate traces of contaminating toxin B chains. The simplest procedure is to pass the A chain preparation over a column of Sepharose-linked asialofetuin, to which the B chains bind avidly (4,11)... 

The ricin and abnn A chains used to block high affinity binding sites on the column should be alkylated to remove the free sulfhydryl group that could interfere with conjugate purification... 

Knowles, P. P. and Thorpe, P. E. (1987) Purification of immunotoxins containing ricin A chain and abrin A chain using Blue Sepharose CL-6B. Anal Biochem. 160,440-443. 

Multiple purification-schemes have been applied to the separation of the toxin and the hemagglutinin.144,146,147,150,194,64,-651 Fractionation using salt and ethanol precipitation led to crystallization844,645 of the toxin known as ricin or ricin D. The hemagglutinin was isolated, free from toxic activity, by ion-exchange chromatography and gel filtration.642,646-648 With the introduction of affinity chromatography on Sepharose 4B, to which both proteins bind, purification of the two R. 

Ishiguro, M., Takahashi, T., Funatsu, G., Hayashi, K., Funatsu, M. (1964a). Biochemical studies on ricin. I. Purification of ricin. J. Biochem. 55 587-92. 

In the case of ricin A chain, a proportion of unreacted RIP binds irreversibly to the S-200 column during the final purification. Tlie column can be cleaned by washing with O.lMNaOH before further chromatography. 

The total quantity of ricin produced or stored within castor seeds depends on the genetic composition of the plant and the growth conditions. As a general guide, published purification methods may yield 1-2 mg of ricin/g of castor seed meal starting material (Ishiguro et al., 1964a Olsnes and Pihl, 1977 Parker et al., 1996). 

Helmy, M. and Pieroni, G. (2000) RCAgo purification and characterization of ricin D isoforms from Ricinus sanguineus. J Plant Phys, 156, 477 82. 

Enrichment of microbial toxins including ricin, SEE, andbotulinum neurotoxins (BoNT) has been performed using multiplex-immuno-affinity purification. Specific monoclonal antibodies for each of the four toxins were selected from a pool of antibodies, the selected antibodies allowed for the specific and simultaneous capture of toxins. This assay enabled unambiguous identification of toxins in complex food matriees with a detection limit of 500 fmol. Additionally, it allowed for the rapid differentiation of closely related BoNT sero- and subtypes ((Kull et al. 2010). 

Acid treatment of agarose increases the number of D-galactose end-groups in the molecule. The hydrolysed matrix has been used successfully for the affinity chromatographic separation of two polypeptide chains from ricin for the purification of a galactan-reactive agglutinin from Tridacna maxima, and for the purification of a lectin from Viscum alburn. ... 

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