Enterobacteria Flashcards
Enterobacteria are oxidase negative. What does this mean?
They do not have cytochrome c oxidase (distinguishes pseudomonas from other gram negatives)
Enterobacteria ferment lactose. How is this tested?
red colonies on MacConkey agar, dark colonies (w/ green sheen) on EMB agar
True or False? Enterobacteria has resistance to bile salts.
True
What is the indole test?
Test for tryptophanase which converts tryptophan to indole (red w/ Kovac’s reagent)
Does enterobacteria contain tryptophanase?
No
Where is enterobacteria found?
soil, water, vegetation, and microbial flora of animals and humans
Some enterobacteria are always associated with disease and some are normal flora that can become pathogenic. Name one that is always pathogenic and 2 that are not.
Pathogenic: Shigella
Can become pathogenic: E. Coli, K. pneumoniae
Name 7 infections caused by enterics?
gastrointestinal infections (watery diarrhea)
dysentery (bloody diarrhea)
skin and wound infections
enteric fever/ Typhoid fever
septicemia (blood infection)
meningitis (inflammation, infection of fluid around brain and spine)
urinary tract infections
What is the second leading cause of deaths among children in developing countries?
diarrhea
What are E. Coli and the Coliforms
- E. Coli
- K. pneumoniae
- E. aerogenes
- S. marcescens
- citrobacter species
Where are E. Coli and the Coliforms found?
soil, water, vegetation, microbiota
Presence of coliforms in water is an indication of what?
fecal contamination
What illnesses are caused by E. Coli?
- extra-intestinal E. Coli
- neonatal meningitis
- UTIs
- gastroenteritis
