Ricinus communis castor bean lectins

Lectin toxicity - nausea, diarrhea, headache, confusion, dehydration, death Wisteria, castor bean (Ricinus communis) Lectins bind to cell surfaces Ricin - blocks protein synthesis, very toxic, 5 to 6 beans can kill a child... 

Ricin was found by Stillmark in 1889 as the first plant lectin derived from the seeds of the castor plant, Ricinus communis L., a member of the Euphorbiaceae or spurge family. Other members of this family include the popular houseplants poinsettia E. pulcherrima), and the croton species. The term castor bean is used commonly to refer to both the plant and seed of R. communis. Ricinus communis commonly grows along streams and riverbeds in addition to subtropical locations high in nutrients. Ricinus communis is a coarse perennial, 10-13 m tall in the tropics, with a stem 7.5-15 cm... 

The most studied RNA A-glycosidase is ricin, from the castor oil bean, Ricinus communis. This toxin has two component chains, the A chain, containing the A-glycohydrolase, and a B chain which is a lectin (a protein which binds carbohydrate structures, in this case galactopyranose), which facilitates... 

A preproricin gene from Ricinus communis has been characterized by both cDNA [31] and genomic [150] cloning. Southern blot analysis has indicated that the Ricinus communis genome includes at least six lectin genes [150], In our laboratory we constructed a cDNA library using ripening castor bean endosperm poly(A)+ RNA which had been enriched for lectin precursor... 

Ricin is a 66-kilodalton (kd) globular protein that makes up 1% to 5% by weight of the bean of the castor plant, Ricinis communis. The toxic heterodimer consists of a 32-kd A-chain that is disulfide-bonded to a 32-kd B-chain.21 The toxin is stored in the matrix of the castor bean, together with a 120,000-d ricinus lectin.22 Both chains are glycoproteins containing mannose carbohydrate groups the two 32-kd chains must be associated for toxicity. 

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