|MadSci Network: Chemistry|
Ricin is the name given to a mixture of natural products isolated from the castor bean. There are four major components; RCL I, RCL II, RCL III (also refered to as ricin D), and RCL IV. The toxic components of ricin are made up of two protein chains crosslinked with a disulfide (S-S) bond. The molecular weight of the toxin is about 63,000 Da. Ricin is among the most toxic compounds known. For more information check out the book chapter; "The Structure and Toxic Functions of Ricin" in Proteins, Structure and Function, vol 2., M. Funatsu et al., eds., Wiley, NY, 1972, pp. 103-139. [Editors note: Proteins of 63,000 molecular weight cannot be formulated like water = H2O. There are, however, ricin derivatives such as ricinoleic acid that can be so defined. But you didn't ask about them...]
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