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Cry3Bb1
Delta endotoxins (δ-endotoxins) are pore-forming toxins produced by ''Bacillus thuringiensis'' species of bacteria. They are useful for their insecticidal action and are the primary toxin produced by Bt maize/corn. During spore formation the bacteria produce crystals of such proteins (hence the name Cry toxins) that are also known as parasporal bodies, next to the endospores; as a result some members are known as a parasporin. The Cyt (cytolytic) toxin group is a group of delta-endotoxins different from the Cry group. Mechanism of action When an insect ingests these proteins, they are activated by proteolytic cleavage. The N-terminus is cleaved in all of the proteins and a C-terminal extension is cleaved in some members. Once activated, the endotoxin binds to the gut epithelium and causes cell lysis by the formation of cation-selective channels, which leads to death. For many years there was no clarity as to the relationship between aminopeptidase N and Bt toxins. Althou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MON 863
MON 863 is a genetically engineered variety of maize produced by Monsanto. It is genetically altered to express a modified version of Cry3Bb1, a delta endotoxin which originates from ''Bacillus thuringiensis''. This protects the plant from corn rootworm. Unlike MON 810, Bt 11, and Bt 176 which each produce a modified Cry1Ab, MON 863 instead produces a modified Cry3Bb1 toxin and contains nptII, a marker gene for antibiotic resistance. History In 2004, Monsanto sought approval in Europe to introduce MON 863. Approval was granted in 2005 for use in feed and in 2006 for use in food. There was controversy over acceptance by regulatory bodies of industry-funded toxicity studies and over the design of those studies led by Pr Gilles-Éric Séralini, who was on the committee that reviewed MON863 for the French government. See Genetically modified food controversies for details of this controversy, which extended beyond MON 863. Following legal action by parties including the Swedish ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |