Enterobacteriacea

Question 1

Phenotype Features

Answer 1

Glucose Fermenter
Catalase Positive
Oxidase Negative
Nitrase Positive

Question 2

Specimen Collection

Answer 2

Stool Collection + Cary-Blair / Amies / Staurt Media + Enrichment Broth

Question 3

Media

Answer 3

Primary: Blood + MAC

Selective & Differential: HE & XLD

Question 4

E. coli vs. EHEC

Non-motile

Answer 4

E.coli - MUG Positive

EHEC - MUG Positive + Use S-MAC to culture

Question 5

Klebiella vs. E. coli

Non-motile

Answer 5

Klebiella - Has capsules / IMViC –++ / Gas production

E. coli - IMViC ++–

Question 6

Serratia

Motile

Answer 6

Motile
Produces Red pigment (Prodigiosin)
Late Lactose Fermenter - Still a non-lactose fermenter

Question 7

PAD Positives

Also all are K/A + Motile

Answer 7

Proteus - Swimmer~Swarmer / H2S Positive
Morganella Morgani - No Swarming / Catalase Negative
Providencia - No Swarming / Catalase Positive

Question 8

Pathogenic Ones

Answer 8

Salmonella / Shigella / Yersinia

Question 9

Salmonella

Answer 9

Motile
More positive on biochemical test
HE Media - Black
XLD Media - Red w/ black center
Test: O antigen and Vi (capsule) antigen
Main focus: S. enterica serotype typhi - causes Typhoid Fever + Salmonella Gastroentertis

Question 10

Shigella

Answer 10

Non-motile
More negative on biochemical test
HE Media - Green
XLD Media - Colorless
Causes Shigellosis (self-limiting)

Question 11

Yersinia

Answer 11

Non-motile
Grows better in cold temps
Safety pin appearance
Bio-terrorism Agent
Slow grower (grows @ 48 hours)