Enterobactenaceae / Opportunistic Pathogens Flashcards
also known as “FRIEDLANDER’S BACILLUS”
Klebsiella spp.
General characteristics of klebsiella spp.
Gram stain
02 requirement
Motility on SIM
Describe Texture of Colonies
Quellung Test
TSI
Indole
MR/VP
Citrate
ODC
Urease
Gram stain: Gram negative
02 requirement: Facultative anaerobe
Motility on SIM: Negative
Describe Texture of Colonies: Mucoid/S colonies
Quellung Test: Positive, capsule
TSI: A/A, G+, Lactose fermenter
Indole: Negative
MR/VP: MR (-), VP (+)
Citrate: Positive
ODC: Negative
Urease: Positive
ORNITHINE DECARBOXYLASE TEST on Klebsiella spp.
Medium:
CHO:
AA:
pH indicator:
Medium: Purple broth
CHO: Glucose
AA: Ornithine
pH indicator: Bromcresol purple (turns yellow in acid)
ORNITHINE DECARBOXYLASE TEST Detects the ability of the bacteria to decarboxylate Ornithine as a source of Carbon to form the alkaline product, ______
Putrescine
Turns the medium back to purple when ODC is released, from being yellow as a result of Glucose fermentation.
ORNITHINE DECARBOXYLASE TEST
Positive and negative for Ornithine Decarboxylase (ODC)
+ Purple
- Yellow
Detects the ability of the organism to produce urease which breaks down urea into ammonia and CO2.
Urease
pH indicator of urease
Phenol red
resembles Klebsiella spp., except that they are MOTILE & ODC (+)
Enterobacter spp.
Enterobacter spp. examples
Enterobacter aerogenes
Enterobacter cloacae subsp. cloacae
General Characteristics of Enterobacter spp.
Gram stain:_________________________________________
O2 requirement:_____________________________________ SIM:_______________________________________________ TSI:_______________________________________________
Presence of Capsule:__________________________________ IMVC:_____________________________________________ Urease:_____________________________________________ ODC:______________________________________________
Gram stain: Gram negative bacilli
O2 requirement: Facultative anaerobe
SIM: - - +
TSI: A/A, G+
Presence of Capsule: Present
IMVC: - - ++
Urease: +
ODC: +
E. aerogenes VS E. cloacae
LOA
E. aerogenes: ++-
E. cloacae: -++
the agent of “RED BREASTMILK”
Serratia spp.
The red pigment produced by S. marcescens is also known as
2-methyl-3-amyl-6-methoxyprodigiosene.
General Characteristics of Serratia spp.
TSI
ONPG test
Urease
DNAse test
Lipase
Gelatinase
TSI: K/A
ONPG test: Positive
Urease: Positive
DNAse test: Positive
Lipase: Positive
Gelatinase: Positive
Serratia marcescens
SIM
IMVC
SIM: - -+
IMVC: - - ++
a facultative anaerobe, H2S positive, verticaclly-transmitted bacteria
Citrobacter spp.
General Characteristics of Citrobacter spp.
TSI:
ONPG:
ODC:
TSI: K/A, H2S+
ONPG: Positive
ODC: Positive
Citrobacter freundii
SIM
IMVC
SIM: +_+
IMVC: -+-+
The rapid urease, non-lactose fermenter group.
Proteus-Providencia-Morganella
Proteus-Providencia-Morganella
Phenylalanine Deaminase
Motility
Methyl red
H2S
Proteus: ++++
Providencia: +++-
Morganella: +++-
The “burnt chocolate” odor, and kidney stone-former.
Proteus spp.
Proteus spp. examples
Proteus mirabilis
Proteus vulgaris
P. vulgaris and P. mirabilis
LOA
Indole
Chloramphenicol
Ampicillin & Cephalosporins
P. vulgaris
LOA: -,-,-
Indole: Red, Positive
Chloramphenicol: R
Ampicillin & Cephalosporins: R
P. mirabilis
LOA: -+-
Indole: Yellow, Negative
Chloramphenicol: S
Ampicillin & Cephalosporins: S
causative agent of Fowl cholera
Providencia spp.
P. rettgeri VS P. stuartii
Urease: Pink - Mostly yellow
Ribitol/Adonitol fermentation: Acid is produced - Absence of acid
Trehalose fermentation: Absence of acid - Acid is produced
P. rettgeri
Urease: +
Ribitol/Adonitol fermentation: +
Trehalose fermentation: -
P. stuartii
Urease: Mostly -
Ribitol/Adonitol fermentation: -
Trehalose fermentation: +
Morganella spp. examples
Morganella morganii subsp. morganii
M. morganii subsp. sibonii
Providencia VS Morganella
H2S: No blackening - No blackening
Gas production: Intact TSI - Raised/Cracked TSI
Citrate: Blue - Green
Prividencia
H2S: -
Gas production: -
Citrate: +
Morganella
H2S: -
Gas production: +
Citrate: -
