Recombinant Bacillus thuringiensis subsp. kurstaki Pesticidal crystal protein cry1Ac (cry1Ac), partial

The Recombinant kurstaki cry1Ac protein is a protein encoded by recombinant DNA that was cloned in an expression vector that supported the expression of cry1Ac gene. This recombinant cry1Ac protein was expressed in the host. The expression region is 972-1178aa of the kurstaki cry1Ac. In the production, the expression vector contains N-terminal GST tag. Every production step was performed with a strict QC system. The purity of this protein is 90%+ determined by SDS-PAGE.

The Cry1Ac protoxin, which is a delta-endotoxin produced during the sporulation phase of Bacillus thuringiensis, has been proposed as an effective and safe alternative adjuvant. When ingested by susceptible larvae, the crystal protein is solubilized and processed, generating the Cry1Ac toxin, which has been widely used as a bioinsecticide. The recombinant Cry1Ac protoxin is immunogenic and adjuvant at the systemic and mucosal level, which can activate antigen presenting cells (APCs) by upregulating costimulatory molecules and increasing the production of pro-inflammatory cytokines. It can confer protective immunity against distinct infection models and remarkably in a murine brucellosis model, it showed the capacity to induce both Th1 and TCD8+ cytotoxic lymphocyte responses, suggesting a potential utility to improve tumor immunity. Beyond this, a study found that a differential adjuvant capacity of Cry1Ac proteins to improve tumor immunity, being the effect of Cry1Ac protoxin outstanding compared with that of Cry1Ac toxin. In addition, Cry1Ac protoxin may confer therapeutic benefit when coadministered with doxorubicin.