A novel gene that regulates the alpha-toxin (plc), kappa-toxin (colA), and theta;-toxin (pfoA) genes was identified using toxin-negative mutant strains of Clostridium perfringens. The cloned 3.2-kb fragment contained the virX gene encoding a 51-amino acid polypeptide of unknown function that seemed to be responsible for the activation of toxin genes. The virX knock out mutant of wild-type strai...

Antimicrobial treatment of Shiga toxin-producing Escherichia coli (STEC) infections is controversial because antimicrobials may stimulate toxin (Stx) production, and thereby increase the risk developing haemolytic uremic syndrome (HUS). Previous in vitro studies have shown this mainly caused by STEC serotype O157:H7. The aim study was to investigate induction Stx transcription production differ...

The virulence of many bacterial pathogens, including the important human pathogen Staphylococcus aureus, depends on the secretion of frequently large amounts of toxins. Toxin production involves the need for the bacteria to make physiological adjustments for energy conservation. While toxins are primarily targets of gene regulation, such changes may be accomplished by regulatory functions of th...

Abstract Background Toxin-antitoxin (TA) systems, abundant in prokaryotes, are composed of a toxin gene and its cognate antitoxin. Several toxins implied to affect the physiological state stress tolerance bacteria population. We previously identified chromosomally encoded hok - sok type I TA system Erwinia amylovora , causative agent fire blight disease on pome fruit trees. A high-level inducti...

elaboration of different toxins by enterotoxigenic e. coli has been considered as one of the main virulence factors contributing to the manifestation of disease caused by these microorganisms. various strategies have been employed to raise antibodies against these toxins as a line of defense. in this study, the 3’ terminus of the gene that codes for the binding subunit of the heat-labile entero...

To determine the expression level of Shiga toxin (Stx) 2-related toxins (Stx2 and Stx2c) produced by each of 33 Stx-producing Escherichia coli (STEC) O157 strains, stx2 and stx2c mRNAs (stx2-related mRNA) were measured using real-time PCR with primers that recognize sequences common to stx2 and stx2c. The amount of Stx2 and Stx2c protein was measured using a reversed passive latex agglutina...

BACKGROUND AND OBJECTIVES Clostridium perfringens, a Gram-positive obligate anaerobic bacterium, is able to form resistant spores which are widely distributed in the environment. C. perfringens is subdivided into five types A to E based on its four major alpha, beta, epsilon and iota toxins. The aim of the present study was cloning and expression of C. perfringens type D vaccine strain epsilon ...

Objective: Cholera is an acute secretory diarrhea caused by the Gram-negative bacterium, Vibrio cholerae mostly through production of cholera toxin (CT) and zonula occludens toxin (Zot).<span style="fon...

introduction: g-proteins have an important role in the cell signaling of numerous receptors. the situation of g-proteins in health and disease and their critical role in the development of diabetic side effects is an interested scientific field. here, the changes in the expression of g-protein subunits (gαi, gαs and gβ) were evaluated in hyperglycemic situation of pc12 cells as a cellular model...