RESUMEN
A large-scale outbreak of food poisoning caused by consumption of skimmed milk powder contaminated with staphylococcal enterotoxin A (SEA) occurred in Japan. No viable Staphylococcus aureus was detected in the skimmed milk powder, however, sea and nuc genes of S. aureus were detected in it by PCR. The number of S. aureus in skimmed milk powder was estimated by quantitative real-time PCR.
Asunto(s)
Enterotoxinas/metabolismo , Leche/metabolismo , Leche/microbiología , Intoxicación Alimentaria Estafilocócica/metabolismo , Animales , Proteínas Bacterianas , Cartilla de ADN , Endonucleasas , Enterotoxinas/genética , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunoensayo , Japón , Nucleasa Microcócica , Reacción en Cadena de la Polimerasa , Intoxicación Alimentaria Estafilocócica/genéticaRESUMEN
It was believed that food poisoning in Osaka in 2000 was due to small amounts of staphylococcal enterotoxin A (SEA) in reconstituted milk. Results of this study clearly indicate that SEH was also present in the raw material of reconstituted milk, indicating that the food poisoning was caused by multiple staphylococcal enterotoxins.
Asunto(s)
Brotes de Enfermedades , Enterotoxinas/toxicidad , Leche/microbiología , Intoxicación Alimentaria Estafilocócica/epidemiología , Animales , Enterotoxinas/análisis , HumanosRESUMEN
A total of 22 clonal phenotypic variants of Shiga toxin (Stx)-producing Escherichia coli (STEC) O157:H7 was isolated from six different locations in Hokkaido, Japan. These isolates were negative for sorbitol fermentation but positive for beta-D-glucuronidase (GUD+). They carried eaeA, EHEC-hlyA, pas and etpD genes like typical E. coli O157:H7 and, in addition, st1 and stx2 genes. However, they were shown to lack katP and espP genes that are present in typical STEC O157:H7. All these atypical GUD+ STEC O157:H7 isolates had very similar antimicrobial susceptibilities. Pulsed-field gel electrophoresis analysis with XbaI, SfiI, SwaI, SpeI and NotI indicated that they were identical or closely related to one another. From their phenotypic and genotypic features, these GUD+ STEC O157:H7 isolates may represent a distinct clone among STEC O157.