The genetically modified (GM) maize event MON810 has been inserted with a processed version of the transgene, cry1Ab, derived from the soil bacterium Bacillus thuringiensis (Bt) to express proteins with insecticidal properties. Such proteins may introduce new allergens and also act as adjuvants that …

A highly active toxin, Cry1Ab, exhibited weaker binding affinity compared to a less active toxin, Cry1Ac. Further, in B. mori Cry1Aa and Cry1Ab showed similar binding affinities for BBMVs, but the biological activity of Cry1Aa was found to be 100-fold higher than Cry1Ab in the insect (51).

针对鳞翅目害虫具有高活性的Cry1Ab 与Cry1Ah 蛋白开展研究，构建了Cry1Ab、Cry1Ah 的杂合蛋白AhAhAb 并测定了杀虫活性。 结果显示，Cry1Ab、Cry1Ah 的结构域交换引起蛋白杀虫活性的显著变化，与出发蛋白相比，杂合蛋白AhAhAb 丧失了对棉铃虫杀虫活性，降低了对玉米螟 ...

We isolated several mutants with single Cys residues in the three domains of Cry1Ab toxin and analyzed their insertion into the membrane using fluorescence spectroscopy and quenching analysis with different soluble quenchers as well as a membrane-bound quencher to compare the properties of the soluble and membrane-inserted forms of Cry1Ab toxin.

Cry1Ab and Cry1Ac proteins are Bt toxins that kill some key Lepidoptera insects, such as the three main cotton pests, Heliothis virescens, Pectinophora gossypiella, and Helicoverpa armigera, as well as some maize insect pests, such as Helicoverpa zea and Ostrinia nubilalis .

2013年7月5日 · The results showed that Cry1A.105, Cry1Ab, Cry1Ac and Cry1Fa competed with high affinity for the same binding sites in both insect species. However, Cry2Ab and Cry2Ae did not compete for the binding sites of Cry1 proteins.

Bacillus thuringiensis Cry toxins are used worldwide for controlling insects. Cry1Ab is produced as a 130-kDa protoxin that is activated by proteolytic removal of an inert 500 amino-acid-long C-terminal region, enabling the activated toxin to bind to insect midgut receptor proteins, leading to its membrane insertion and pore formation.

Cry1ab/ac gene was fused by both the cry1ab gene (GenBank Accession No. X54939) and the cry1ac gene (GenBank Accession No. Y09787), which was widely used in genetically modified (GM) rice, cotton, maize and so on. In order to support the safety assessment of GM food or feed products containing Cry1A …

2008年5月5日 · Our study present mutants in domain II of the Cry1Ab toxin, at position F371, that allow receptor binding but prevent insertion of the toxin into the membrane. Proteinase K protection combined with steady state fluorescence measurements of labeled toxin molecules effectively demonstrates that the residue F371 plays a role in the mechanism of ...

2003年9月9日 · Molecular basis for Bacillus thuringiensis Cry1Ab toxin specificity: two structural determinants in the Manduca sexta Bt-R1 receptor interact with loops alpha-8 and 2 in domain II of Cy1Ab toxin Biochemistry .