The sporulation-specific enterotoxin of Clostridium perfringens type A, which is the toxin active in human food poisoning, has been purified from extracts of sporulating cells. Highly purified enterotoxin was obtained by treatment of crude cell extract with ribonuclease for 30 min, followed by sequential chromatography on Sephadex G-100, Cellex T cellulose, and hydroxylapatite. Recovery was 65 ...

The cross-reactivity of monoclonal antibodies produced against staphylococcal enterotoxin A with purified and crude enterotoxins B, C1, D, and E and the specificity of such reactions were evaluated by the indirect enzyme-linked immunosorbent assay and immunoblotting of Western blots (from sodium dodecyl sulfate-polyacrylamide gel electrophoresis) followed by autoradiography. Purified and crude ...

The biosynthesis of enterotoxin A by replicating and nonreplicating cells was investigated. Unlike enterotoxin B, a secondary metabolite, enterotoxin A secretion resembled that of a primary metabolite by being secreted during the exponential phase of growth. The amount of toxin produced per unit of growth was not influenced by NaCl, NaNO(2), or NaNO(3). Several surfactants increased toxin secre...

Staphylococcus aureus enterotoxin D is one of the serotypes most commonly associated with food poisoning. Further characterization of the enterotoxin D-encoding plasmid revealed the presence of an open reading frame which encodes a previously unidentified enterotoxin, designated staphylococcal enterotoxin J (SEJ). SEJ is a protein of 269 amino acid residues which has substantial sequence simila...

The ability of Clostridium perfringens type A to produce an enterotoxin active in human food poisoning has been shown to be directly related to the ability of the organism to sporulate. Enterotoxin was produced only in a sporulation medium and not in a growth medium in which sporulation was repressed. Mutants with an altered ability to sporulate were isolated from an sp(+) ent(+) strain either ...

The in vitro exposure of staphylococcal enterotoxin B to trypsin resulted in the formation within 30 min of a product (enterotoxin-T) unchanged in molecular weight, but with threonine as a second NH2 terminus. Upon reduction of the -SSbridge in enterotoxin-T, two fragments were separated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. The peptide bond between Lys-97 and Thr-98 ...

The in vitro exposure of staphylococcal enterotoxin B to trypsin resulted in the formation within 30 min of a product (enterotoxin-T) unchanged in molecular weight, but with threonine as a second NH2 terminus. Upon reduction of the -SSbridge in enterotoxin-T, two fragments were separated by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. The peptide bond between Lys-97 and Thr-98 ...

ABSTRACT: The aim of this study was to molecularly identify different species Aeromonas isolated from farmed tambaqui (Colossoma macropomum) North Brazil, and evaluate their pathogenic potential by the presence virulence genes. From extraction bacterial DNA, PCR (polymerase chain reaction) primers 16S rDNA, aerA (cytolytic enterotoxin), ast (cytotoxic enterotoxin) act were performed. Of 24 isol...

background: in this study we aimed at detecting the enterotoxin a and b gene of s. aureus in clinical samples of patients attending health centers in zahedan using molecular methods. materials and methods: a cross-sectional study was carried out in which 40 samples of s. aureus were obtained from patients in a hospital in zahedan, iran. following the biochemical tests, identifications were conf...