LaeA and VeA coordinate secondary metabolism and differentiation in response to light signals in Aspergillus spp. Their orthologs, ChLae1 and ChVel1, were identified in the maize pathogen Cochliobolus heterostrophus, known to produce a wealth of secondary metabolites, including the host selective toxin, T-toxin. Produced by race T, T-toxin promotes high virulence to maize carrying Texas male st...

Streptolysin-O was isolated from culture supernatants of group-A beta-hemolytic streptococci (Richards strain) by ammonium sulfate and polyethylene glycol precipitation, DEAE-ion exchange chromatography, preparative isoelectric focusing, and chromatography on Sephacryl S-300. Two forms of the toxin possessing similar hemolytic capacity were identified. The native toxin was a single polypeptide ...

clostridium difficile has been recognized as the major cause of pseudomembranous colitis.this bacterium produces two toxins(an enterotoxin -cytotoxin and a potent cytotoxin called toxin A and toxin B erespectively).these toxins have implicated in pathogenesis of the disease.however,histopathological effects of their molecular mass less than 100KDa have been essayed.in the persent study,we exami...

Our aim was to evaluate the short and long term efficacy of botulinum toxin therapy in Iranian patients with achalasia. In a randomized, double blind trial, 20 patients with achalasia, referring to Imam Khomeini Hospital, received either 80 units of botulinum toxin (BT) or placebo (PL) from 1995 to 1998. Two weeks later, the response to treatment was assessed on the basis of changes in the...

When 3,972 ground beef enrichments with 6 confirmed to contain a non-O157 Shiga toxin-producing intimin-positive Escherichia coli isolate were tested for Shiga toxin, intimin, and O group (O26, O45, O103, O111, O121, and O145) genes, 183 potential positives and only 2 of the 6 confirmed positives were identified.

Reduced tissue perfusion leading to tissue ischemia is a central component of the pathogenesis of myonecrosis caused by Clostridium perfringens. The C. perfringens alpha-toxin has been shown capable of inducing these changes, but its potential synergy with perfringolysin O (theta-toxin) is less well understood. Similarly, Clostridium septicum is a highly virulent causative agent of spontaneous ...

I N T R O D U C T I O N Saxi toxin (STX) and te t rodotoxin ( T T X ) are small organic molecules tha t specificially block sodium channels in m a n y exci table membranes . T h e physical chemical propert ies o f the receptor for S T X and T T X have been s tudied in bo th electrophysiological exper iments and in b ind ing exper iments with rad io labe led toxins. Earl ier results revealed s t...

Clostridium perfringens causes gas gangrene and gastrointestinal disease in humans. These pathologies are mediated by potent extracellular protein toxins, particularly α-toxin and perfringolysin O (PFO). While α-toxin hydrolyzes phosphatidylcholine and sphingomyelin, PFO forms large transmembrane pores on cholesterol-containing membranes. It has been suggested that the ability of PFO to perfora...

Aerolysin is a pore-forming toxin that plays a key role in the pathogenesis of Aeromonas hydrophila infections. In this study, we have analyzed the effect of aerolysin on human granulocytes (HL-60 cells). Proaerolysin could bind to these cells, was processed into active aerolysin, and led to membrane depolarization, indicating that granulocytes are potential targets for this toxin. Fura-2 measu...