Bordetella pertussis and Bacillus anthracis produce extracytoplasmic adenylate cyclase toxins (AC toxins) with shared features including activation by calmodulin and the ability to enter target cells and catalyze intracellular cyclic AMP (cAMP) production from host ATP. The two AC toxins were evaluated for sensitivities to a series of inhibitors of known uptake mechanisms. Cytochalasin D, an in...

Th e cry3Aa11 gene of Bacillus thuringiensis strain Mm2 (B. thuringiensis Mm2) was PCR-amplifi ed and cloned into E. coli/B. thuringiensis shuttle vector pHT315. Th e recombinant plasmid carrying the cry3Aa11 gene was introduced into the parental B. thuringiensis Mm2. Th e toxin production capacities of parental and recombinant strains grown in DSM, containing either 50 mM or 200 mM inorganic p...

AB5 toxins are composed of an enzymatic A subunit that disrupts cellular function associated with a pentameric B subunit required for host cell invasion. EcxAB is an AB5 toxin isolated from clinical strains of Escherichia coli classified as part of the cholera family due to B subunit homology. Cholera-group toxins have catalytic ADP-ribosyltransferases as their A subunits, so it was surprising ...

One hundred representative strains of Bacillus cereus were selected from a total collection of 372 B. cereus strains using two typing methods (RAPD and FT-IR) to investigate if emetic toxin-producing hazardous B. cereus strains possess characteristic growth and heat resistance profiles. The strains were classified into three groups: emetic toxin (cereulide)-producing strains (n=17), strains con...

We have determined the nucleotide sequence of the sltA and sltB genes that encode the Shiga-like toxin (SLT) produced by Escherichia coli phage H19B. The amino acid composition of the A and B subunits of SLT is very similar to that previously established for Shiga toxin from Shigella dysenteriae 1, and the deduced amino acid sequence of the B subunit of SLT is identical with that reported for t...

background: cigarette smoking has been linked with the suppression of immune responses and increased susceptibility to numerous infections in humans. tetanus is also a major public health problem in many countries. the aim of the present study was to evaluate the serum levels of anti-tetanus toxin antibodies in c igarette smoking and healthy non-smoking people .   materials and methods: a total...

Various in vitro effects of staphylococcal enterotoxin B (SEB) on human peripheral blood mononuclear cells were mitigated by Bacillus anthracis edema toxin. In particular, levels of some SEB-induced cytokines (tumor necrosis factor alpha, gamma interferon) and chemokines (monocyte chemoattractant protein 1, macrophage inflammatory protein 1 alpha [MIP-1alpha], MIP-1beta) were significantly dimi...

seeds of the castor bean plant ricinuscommunis l (cb) contain ricin toxin (rt), one of the most poisonous naturally-occurring substances known. ricin toxin, a water-soluble glycoprotein that does not partition into the oil extract, is a ribosome-inactivating toxin composed of two chains, labeled a and b. severity of the toxicity varies depending on the route of exposure to the toxin. inhalation...

in this research a molecular method based on polymerase chain reaction for typing of clostridium perfringens was developed and toxin genotypes of 64 isolates from sheep and goats in iran were determined. the pcr assays were developed for detection of alpha (cpa), beta (cpb) and epsilon (etx) toxin genes, allowing classification of the isolates into genotypes a b, c and d. the field isolates ...