A larger-molecular-weight precursor of enterotoxin A was found in membranes of Staphylococcus aureus and was shown to be the kinetic precursor to the extracellular form of the toxin. Subcellular fractionation revealed that mature enterotoxin A was transiently associated with the cell wall before being released to the extracellular environment.

Fusidic acid (FA) is a bacteriostatic antibiotic that locks elongation factor G (EF-G) to the ribosome after GTP hydrolysis during elongation and ribosome recycling. The plasmid pUB101-encoded protein FusB causes FA resistance in clinical isolates of Staphylococcus aureus through an interaction with EF-G. Here, we report 1.6 and 2.3 Å crystal structures of FusB. We show that FusB is a two-domai...

A conjugative plasmid with potential usefulness for vaccine strains was constructed. In the first step, a 5.9-kilobase DNA segment containing the two loci for the A and B subunits of heat-labile enterotoxin with a mutation in the gene for the A subunit was joined to the cloning vehicle pGA22, generating the nonconjugative plasmid pPMC4 with genes for resistance to tetracycline and chloramphenic...

Tryptic hydrolysis after reduction and carboxamidomethylation of staphylococcal enterotoxin B cleaved the single susceptible bond located between the 2 half-cystines of the molecule, Lys-Thr at positions 97 and 98 (Spero, L., Warren, J. R., and Metzger, J. F. (1973) J. Biol. Chem. 248, 7289-7294). The product remained as a single particle but was separated into the two constituent peptides by d...

Studies of staphylococcal food poisoning have been made difficult by the lack of an easy, reliable method for demonstrating the presence of an enterotoxin, elaborated by certain strains of Staphylococcus aureus (Micrococcus pyogenes). The commonly used laboratory animals (guinea pig, mouse, rabbit, rat) are rodents, which as a class lack the appropriate mechanism for vomiting. These animals, th...

Received January 16,1978 SUMMARY: Rat ovarian cells were exposed to cholera enterotoxin, and the effect on progesterone synthesis as well as on protein kinase stimulation was examined. Cholera enterotoxin stimulated ovarian steroidogenesis in a dose dependent manner similar to that of hCG. The stimulation of protein kinase by cholera toxin was followed by a lag period, whereas hCG effect was im...

objective: the number of new cancer cases with considerable mortality is increasing worldwide. since the inability of current therapies in treatment of patients and prevention the progress of tumors with fewer side effects, implementation of new methods is needed. gene therapy has widespread systemic cytotoxic effects against tumor cells. rotavirus nsp4 has been shown to elicit extensive cytoto...

materials and methods two-hundred pasteurized (n = 100) and nonpasteurized (n = 100) cheese samples were collected. the initial isolation was performed on pemba specific medium. antibiotic susceptibility testing was performed using several antibiotic disks, according to the guidelines of the clinical laboratory and standards institute. specific primers amplifying the hbla enterotoxin-encoding g...

background and objectives: staphylococcal food poisoning is a gastrointestinal disease, which is caused by consumption of contaminated food with enterotoxins produced by staphylococcus aureus (ses). milk and its products are known sources of food borne diseases. this study was carried out to evaluate the prevalence of enterotoxigenic s. aureus strains in organic milk and cheese in tabriz - iran...

results in total, 80 food samples suspected of seb contamination were assessed using the two methods. fifty-four samples were contaminated based on the pcr technique and twenty-six of those were confirmed using the strip assay. conclusions the sensitivity of the sandwich method was approximately 10 ng/ml and that of the competitive method was approximately 250 ng/ml. in the lfd, a highly specif...