Bacillus thuringiensis: from biodiversity to biotechnology.
Bacillus thuringiensis is a Gram-positive bacterium, widely used in agriculture as a biological pesticide. The biocidal activity mainly resides in a parasporal protein inclusion body, or crystal. The inclusion is composed of one or more types of delta-endotoxins (Cry and Cyt proteins). Cry proteins are selectively toxic to different species from several invertebrate phyla: arthropods (mainly insects), nematodes, flatworms and protozoa. The mode of action of the insecticidal proteins is still a matter of investigation; generally, the active toxin is supposed to bind specific membrane receptors on the insect midgut brush-border epithelium, leading to intestinal cell lysis and subsequent insect death by starvation or septicemia. The toxin-encoding cry genes have been extensively studied and expressed in a large number of prokaryotic and eukaryotic organisms. The expression of such genes in transgenic plants has provided a powerful alternative for crop protection.
Prieto-Samsónov
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Laboratory of Environmental Biotechnology, Centre for Genetic Engineering and Biotechnology (CIGB), Havana, Cuba.
Vázquez-Padrón
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Ayra-Pardo
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González-Cabrera
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de la Riva
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GA
D001413:Bacillus thuringiensis / Q000502:physiology*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology; D001427:Bacterial Toxins; D004731:Endotoxins / Q000096:biosynthesis* / Q000737:chemistry / Q000494:pharmacology; D006460:Hemolysin Proteins; D007305:Insecticide Resistance; D010572:Pest Control, Biological; D030821:Plants, Genetically Modified; D011994:Recombinant Proteins / Q000096:biosynthesis*
D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D011994:Recombinant Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis