Ricin toxin native

RIPs should generally appear as a single band on SDS-PAGE. The presence of additional bands is a clear indication of impurity, and may complicate the interpretation of electrophoretic analysis of conjugate products. The exception is ricin A chain that has been isolated from the native toxin. Native ricin A chain exists as a mixture of two differently... 

Production of toxin chimeras is possible by applying similar technology to recombine isolated A- and B-chains from closely related type 2 RlPs (Olsnes and Pihl, 1986). For example, hybrid toxins composed of the modeccin A-chain and RTB have been produced and found to be even more toxic to Vero cells than are native ricin or modeccin (Sundan et al., 1983). Isolated abrin A-chain can be combined with RTB, or abrin B-chain with RTA, to produce chimeras with almost the same toxicity as the native toxins (Olsnes et al., 1974a). Similar experiments have been conducted combining viscumin A-chain and RTB to produce a chimera with cytotoxicity intermediate between that of viscumin and ricin (Tonevitskii et al., 1994). 

Frigerio, L., Vitale, A., Lord, J.M., Ceriotti, A. and Roberts, L.M. (1998) Free ricin A chain, proricin, and native toxin have different cellular fates when expressed in tobacco protoplasts. J Biol Chem, ITi, 14194-14199. 

Native ricin was first shown to inhibit tumor growth in 1951. The toxin was tested by various routes—local application, intratumor, and intraarterial—in patients with tumors, with varying results.8 In recent years, with the advent of new immunotherapeutic techniques, ricin has once again found a niche in the armamentarium of the medical profession. It has been studied as a component of antitumor agents called immunotoxins or, more specifically, chimeric toxins.9... 

Ricin is derived from a common plant, the castor bean (Ricinus communis), and is native to the Mediterranean and Middle East and cultivated elsewhere as an ornamental plant. It is also the source of castor oil, which has many uses in medicine, food, and industry. Ricin is also a highly potent toxin that can kill a person in amounts as small as a few grains of sand. 

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