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Toxin B is essential for virulence of Clostridium difficile
The construction of isogenic tcdA and tcdB mutants of a virulent C. difficile strain are described and their use in the hamster disease model is used to show that toxin B is a key virulence determinant. Expand
Binary Toxin Production in Clostridium difficile Is Regulated by CdtR, a LytTR Family Response Regulator
These studies have shown for the first time that binary toxin production is subject to strict regulatory control by the response regulator CdtR, which is a member of the LytTR family of response regulators and is related to the AgrA protein from Staphylococcus aureus. Expand
Epidemics of diarrhea caused by a clindamycin-resistant strain of Clostridium difficile in four hospitals.
A strain of C. difficile that is highly resistant to clindamycin was responsible for large outbreaks of diarrhea in four hospitals in different states and is a specific risk factor for diarrhea due to this strain. Expand
Familial autoinflammation with neutrophilic dermatosis reveals a regulatory mechanism of pyrin activation
This disease provides evidence that a guard-like mechanism of pyrin regulation, originally identified for Nod-like receptors in plant innate immunity, also exists in humans, which guards against autoinflammation in humans. Expand
Genomic analysis of the erythromycin resistance element Tn5398 from Clostridium difficile.
Using PCR analysis it has been shown that isolates of C. difficile obtained from different geographical locations exhibit heterogeneity in the genetic arrangement of both Tn5398 and their Erm B determinants, which indicates that genetic exchange and recombination between these determinants occurs in the clinical and natural environment. Expand
Functional Identification of Conjugation and Replication Regions of the Tetracycline Resistance Plasmid pCW3 from Clostridium perfringens
Detailed molecular analysis of the tetracycline resistance plasmid pCW3 from C. perfringens has shown that it represents the prototype of a unique family of conjugative antibiotic resistance and virulence plasmids, and provides evidence that a nonreplicating Tn916-like element can evolve to become the conjugation locus of replicatingPlasmids that carry major virulence genes or antibiotic resistance determinants. Expand
Environmental Response and Autoregulation of Clostridium difficile TxeR, a Sigma Factor for Toxin Gene Expression
TxeR, a sigma factor that directs Clostridium difficile RNA polymerase to recognize the promoters of two major toxin genes, was shown to stimulate its own synthesis, supporting a model for toxin gene expression in which synthesis of TxeR is induced by specific environmental signals. Expand
Programmed Cellular Necrosis Mediated by the Pore-Forming α-Toxin from Clostridium septicum
Data show that α-toxin initiates a multifaceted necrotic cell death response that is consistent with its essential role in C. septicum-mediated myonecrosis and sepsis and postulate that cellular intoxication with pore-forming toxins may be a major mechanism by which programmed necrosis is induced. Expand
Clostridium difficile infection
Infection of the colon with the Gram-positive bacterium Clostridium difficile is potentially life threatening, especially in elderly people and in patients who have dysbiosis of the gut microbiotaExpand
The role of toxin A and toxin B in the virulence of Clostridium difficile.
It is becoming increasingly evident that toxin B plays a much more important role than anticipated in Clostridium difficile nosocomial infections, especially in more clinically relevant current epidemic isolates. Expand