These findings are similar to previous reports of protease alterations in other insect species that have developed resistance to Bt toxins
(Oppert et al.
The resulting validated promoters will support IMAmt's product development pipeline of cotton varieties based on Bt toxins
, a family of bacterial genes toxic to insects, and featuring resistance to Boll Weevil, a beetle-like pest which feeds on cotton buds and flowers.
Toxin- receptor interaction is known to be the most crucial and rate limiting step for toxin activity and specificity determination but still very less information is available regarding the receptors of Cry2 proteins and the mechanism of receptor-ligand interactions of BT toxins
Truncated forms of the genes that code for Bt toxins
have been genetically engineered into plants.
Strains of this bacterium produce over 200 different Bt toxins
, each harmful to different insects.
produce insecticidal toxins with oral toxicity similar to that of Bt toxins
, but have not yet been fully utilized.
get adhered to specific binding sites in insect's midgut lining where they unsettle the cytoplasmic membranes making the way to cell lysis.
Monsanto downplayed the findings, saying that Bt toxins
are "inoffensive and break down in the digestive tract.
US government agencies consider the Bt proteins produced by genetically modified (GM) crops to be the same as natural Bt toxins
Compared with typical insecticide sprays, the Bt toxins
produced by genetically engineered crops are much safer for people and the environment, explains study leader Yves Carriere, professor of entomology.
The study looked at the prevalence of Bt toxins
in female patients, finding that the chemicals -- which are often implanted into GMO crops including corn -- were found in the majority of those who were surveyed.
It was reported that the Bt toxins
kill insects by binding to specific target sites and disrupting the midgut tissue followed by septicemia (Raymond et al.