Lecture%208

Lecture%208 - Gram positive Not motile Not food borne...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Gram positive Not motile Not food borne infection Intoxications Consumption of heat stable enterotoxin Stimulates gut receptors-vomit center Infections of the skin Toxin shock syndrome Food borne illness Shares features of enteric family and endospore forming bacteria Poor competitor Does not form spores, does not survive cooking The organism S. aureus is a member of the micrococcus family: Coccus Grape like clusters Skin microbe Common on people with skin infections Handled food has high probability Can be human or animal S. aureus tolerates high concentrations of salt Can grow at salt concentrations as high as 10% w/v, (most bacteria dont >4%) Salt tolerance enables tolerance to dryness Competitive edge in salty foods Ham Cured meats Synthesizes many kinds of extracellular proteins Basis of pathogenicity Permit S. aureus to disrupt host cells and kill macrophages Functions as an enterotoxin Elicits neural responses in the intestines Send signals to the brain causing diarrhea and vomiting The disease Minimum dose: food serving containing at least 5x10 5 cells Incubation period: 2-6 hrs Symptoms: nausea, vomiting, abdominal pain, dehydration with or w/o diarrhea Illness duration: 12-24 hrs Typical foods Food prepared by hand, left unrefrigerated for at least 4 hrs Different kinds of food but best on fatty foods (makes lipase for fat digestion) Does not grow in acidic foods such as mayonnaise but can grow when acid is neutralized by tuna etc Subsequent heating of food does not destroy toxin EXTREMELY heat stable...
View Full Document

Page1 / 26

Lecture%208 - Gram positive Not motile Not food borne...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online