Clostridium difficile infection (CDI) is a common and debilitating nosocomial infection with high morbidity and mortality. C. difficile mediates diarrhea and colitis by releasing two toxins, toxin A and toxin B. Since both toxins stimulate proinflammatory signaling pathways in human colonocytes and both are involved in the pathophysiology of CDI, neutralization of toxin A and B activities may r...

cholera toxin b subunit (ctb) has been extensively studied as an immunogen, adjuvant, and inducer of oral tolerance in many investigations. production of ctb has been carried out in the bacterial, plant, insect and yeast expression systems. in this study the expression of the ctb containing a 6xhis-tagged was performed by escherichia coli (e.coli) m15. the yield of purified pentameric recombina...

With the plasmid DNA from a clinical isolate of enterotoxigenic Escherichia coli (ETEC) H 10407 as template, PCR-mediated cloning of the sequence encoding the heat-labile toxin B subunit (L T -B) has been carried out. Then this sequence was recloned into the pTrc 99A and pET23a expression vectors to give the pJasmids pTRCLTB and pETLTB, respectively. After induction, the former plasmid provides...

Clostridium difficile toxin B (269 kDa) is one of the causative agents of antibiotic-associated diarrhea and pseudomembranous colitis. Toxin B acts in the cytosol of eukaryotic target cells where it inactivates Rho GTPases by monoglucosylation. The catalytic domain of toxin B is located at the N terminus (amino acid residues 1-546). The C-terminal and the middle region of the toxin seem to be i...

Toxin A but not toxin B, appears to mediate intestinal damage in animal models of Clostridium difficile enteritis. The purpose of this study was to investigate the electrophysiologic and morphologic effects of purified C. difficile toxins A and B on human colonic mucosa in Ussing chambers. Luminal exposure of tissues to 16-65 nM of toxin A and 0.2-29 nM of toxin B for 5 h caused dose-dependent ...

We report on a case of scedosporiosis in a 72-year-old German woman. Her disease started with a purulent ulceration of unknown course at her left foot. Soon after onset of oral antibacterial therapy she needed in-hospital treatment because of an acute pneumonia. The infection progressed despite the application of different antibiotics. Microscopic examination of tracheal fluid revealed fungal h...

During a period of 10 to 12 h after injection of type B 16S (L) toxin into the ligated duodenum of rats, 0.01 to 0.1% of the total toxicity administered was found in the lymph drawn by cannulation of the thoracic duct. The recovery was 50 to 100 times higher than that of the rat given type B 12S (M) or 7S (S) toxin. During the same period, 0.6 to 1.5% of the specific antigens were recovered, re...

We examined Bordetella avium for virulence factors common to Bordetella pertussis, including pertussis toxin, filamentous hemagglutinin, adenylate cyclase, dermonecrotic toxin, and tracheal cytotoxin. B. avium produced a dermonecrotic toxin and a tracheal cytotoxin. The dermonecrotic toxin of B. avium is a 155,000-molecular-weight, heat-labile protein which was lethal for mice, guinea pigs, you...

An atypical toxin variant of Clostridium botulinum (strain 657) was isolated from the feces of a 6-week-old female infant whose symptoms and clinical history were consistent with infant botulism. Toxin detected in the feces and the toxin produced by isolates from the feces and from two rectal swabs could be neutralized by type B botulinal antitoxin only at very high ratios of of antitoxin to to...