Difference between revisions of "Part:BBa K3788001"

Latest revision as of 08:27, 21 October 2021

Flag-Cry11Aa

BBa_K3788001 sequence is coding for Cry11Aa, a toxin from Bacillus thuringiensis (Bti). This toxin has a Flag tag in N-ter to allow purification of the protein Cry11Aa and specific detection by Western blot. The gene cry11Aa was optimised for E. coli K12.

Expected size :

flag_cry11Aa gene is 1956bp

Flag-Cry11Aa protein is 70kDa kDa

Mode of action of Cry toxins:

Cry toxins, in the form of a pro-toxin (inactive), will undergo proteolytic cleavage at their N-terminus end, allowing the unmasking of the zone of interaction with the receptor. Mature Cry toxins recognize glycoprotein-type receptors on the surface of midgut cells, more specifically the microvilli of the apical membranes. The II and III domains, forming 3 β-sheets, allow this interaction. Once recognized, domain I, forming 7 amphipathic α-helices, one of which is hydrophobic, is inserted into the membrane to allow the formation of the pre-pore. From this first step emerges the formation of Cry toxins oligomers and the formation of the pore. This allows ion leakage and cell lysis. Following this, an event cascade lead to sepsis resulting in the death of the insect

Cry11Aa and Cyt1Aa. Cry11Aa has a toxic action, specific to A. aegypti because its -8 loop, region -4 and domain II loop 3 recognize the mosquito midgut BBMV receptor. It has been shown that Cyt1Aa would facilitate the binding of Cry11Aa to the BBMV receptor.This interaction allows easy insertion of Cry11Aa into membranes.

Sequence and Features