family enterobacteriacea

• Exterics

  • Part of the normal intestinal flora
  • Cause gastrointestinal disease
• Colony Morphology

  Large and very mucoid colonies
• Enterics

  • Klebsiella
  • Enterobacter
• Presumptive identification


  1. Enterics reaction to TSI

  2. AfA+ gas K/Aga+Has

  3. KA
• Enterics

  • Klebsiella
  • Escherichia
  • Salmonella
  • Shigella
  • Proteus
  • Enterobacter
  • Arizonia
  • Citrobacter
  • Pseudomonas
  • Edwardsiella
• Differential media

  • Contain sodium thiosulfate and ferric ammonium citrate
• Definitive identification

  1. Biochemical reactions

  2. DNA homology
• Virulence of Enterobacteriaceae

  • Ability to adhere
  • Ability to colonize
  • Ability to produce toxins
  • Ability to invade tissues
  • Harboring plasmids that can provide antimicrobial resistance
• Enterobacteriaceae are subcategorized into Tribes
• Tribes are used in classifying the members of Enterobacteriaceae
• Tribes were proposed by Ewing