Thuringiensin: a toxin from Bacillus thuringiensis

Bacillus thuringiensis ( Bt ) is an entomopathogenic bacteria widely used in practice for biological control of insect pests, nematodes and disease vectors. Your toxicity is related to the ability to produce many virulence factors, including thuringiensins (β-exotoxins). Most toxins produce by this microorganism are highly specific, therefore the use of  it in biological control is considered environmentally safe and so this bacteria is extensively used in the production of biological insecticides and genetically modified plants. However, the thuringiensin is considered toxic to almost all life forms, including humans, due to its ability to inhibit the biosynthesis of RNA polymerase, an enzyme essential to the transfer of genetic information in almost all organisms. This way, the release of new strains of Bt with insecticidal properties for the biological control of pests must pass by verification of the absence of production of exotoxin, so that non-target organisms are not affected and the use of Bt in this field remains safe. Thus, this revision will discussed the knowledge about features, structure, genetic determinants, biosynthesis, mechanism of action, insecticide spectrum, security assessment and procedures for identification of thuringiensin in Bt strains.