ABSTRACT
Plant toxins and the bacterial toxins are the best studied cytotoxic proteins. The plant toxins Abrin and Ricin are exceptionally toxic and form a part of the ribosome inactivating proteins (RIPs) that are a large family of N-glycosidases, exhibiting exquisite specificity in their catalytic hydrolysis of a single adenine base from among nearly 7000 nucleotides found in mammalian ribosomes. Owing to the remarkable cytotoxicity of Abrin-a, like Ricin, there is a considerable interest in the search for strong competitive inhibitors. Abrin has been widely used in the design of antitumor agents but has also been used as a potent bio-warfare agent. Effective inhibitors might be useful to help control nonspecific toxicity in treatments with immunotoxins and could also serve as antidotes in poisonings. This report deals with the in silico modeling of Abrin-a-inhibitors complexes using the docking method. Various ringed compounds were analyzed to obtain at least a qualitative understanding of the nature of interactions between the protein and the inhibitors. The details are discussed in the various sections of this chapter.
