title: Bacillus thuringiensis membrane-damaging toxins acting on mammalian cells.
abstract: Bacillus thuringiensis is widely used as a biopesticide in forestry and agriculture, being able to produce potent species-specific insecticidal toxins and considered nonpathogenic to other animals. More recently, however, repeated observations are documenting the association of this microorganism with various infectious diseases in humans, such as food-poisoning-associated diarrheas, periodontitis, bacteremia, as well as ocular, burn, and wound infections. Similar to B. cereus, B. thuringiensis produces an array of virulence factors acting against mammalian cells, such as phosphatidylcholine- and phosphatidylinositol-specific phospholipase C (PC-PLC and PI-PLC), hemolysins, in particular hemolysin BL (HBL), and various enterotoxins. The contribution of some of these toxins to B. thuringiensis pathogenicity has been studied in animal models of infection, following intravitreous, intranasal, or intratracheal inoculation. These studies lead to the speculation that the activities of PC-PLC, PI-PLC, and HBL are responsible for most of the pathogenic properties of B. thuringiensis in nongastrointestinal infections in mammals. This review summarizes data regarding the biological activity, the genetic basis, and the structural features of these membrane-damaging toxins.
authors.affiliation: Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Celandroni
authors.forename: Sara
authors.initials: S
authors.lastname: Salvetti
authors.forename: Sonia
authors.initials: S
authors.lastname: Senesi
authors.forename: Emilia
authors.initials: E
authors.lastname: Ghelardi
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000166:cytology / Q000235:genetics / Q000378:metabolism*; D001427:Bacterial Toxins / Q000378:metabolism / Q000633:toxicity*; D002462:Cell Membrane / Q000187:drug effects*; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006801:Humans
chemical_list: D001427:Bacterial Toxins
keywords: Bacillus thuringiensis; PC-PLC; PI-PLC; hemolysin BL; mammalian infection; toxin