UAMS MICROBIOLOGY- EXAM 2
QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS (GRADED A+)
Microbiology: Enteric Bacilli Biochemical Identification Matrix
What organism is identified by the following biochemical profile?
Voges-Proskauer: No color change (Negative)
Phenylalanine Deaminase: No color change (Negative)
TSI (Triple Sugar Iron): A/A with {H}_2\ (Acid slant / Acid butt,
Hydrogen Sulfide production)
Citrate: Blue (Positive)
Lysine Decarboxylase: Yellow / Control yellow (Negative)
Indole: No color change (Negative)
ONPG: Yellow (Positive - slow/late lactose fermenter)
Urease: Yellow (Negative)
Motility: Positive
Which organism can cause "traveler's diarrhea" in developing countries? -
ANSWER✔✔E. coli
Which organism is typically MUG positive and what does a positive reaction look
like? -ANSWER✔✔E. coli (not E. coli 0157); fluorescence
Which organisms produce lactose positive colonies on MAC and what is the
expected appearance of the organisms? -ANSWER✔✔E. coli, Klebsiella &
Enterobacter are lactose + & produce red/pink colonies
,Which organism causes most urinary tract infections? -ANSWER✔✔E. coli
Voges-Proskauer = Pink; Phenylalanine = No color change
KIA = A/A; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = Yellow
Urea = Pink; Motility = Positive
DNAse = No clearing
What is the identification? -ANSWER✔✔Enterobacter species
Voges-Proskauer = No color change
Phenylalanine = No color change
Kligler iron agar = Yellow/yellow; Citrate = Green
Lysine = Purple (Control tube - yellow); Indole = Red
ONPG = Yellow; Urea = Yellow; Motility = Positive
What is the identification? -ANSWER✔✔Escherichia coli
Which of the Haemphilus species are NOT normal flora? -ANSWER✔✔H.
ducreyi & H. aegyptius
Which two Haemophilus species require X and V factors for growth? -
ANSWER✔✔H. haemolyticus (hemolytic) & H. influenzae (nonhemolytic)
Which two Haemophilus species require V factor for growth? -ANSWER✔✔H.
parahinfluenzae (nonhemolytic) & H. parahaemolyticus (hemolytic)
, Which two Haemophilus species are porphyrin test positive (fluorescence)? -
ANSWER✔✔H. parainfluenzae (no hemolysis present) & H. parahaemolyticus
(hemolysis)
Which organism causes pinkeye? -ANSWER✔✔Haemophilus aegyptius
Which organism is transmitted sexually and causes a chancroid or soft chancre? -
ANSWER✔✔Haemophilus ducreyi
Which gram negative bacilli satellite around staphylococci on sheep blood agar?
What nutrient is supplied by the staphylococci? -ANSWER✔✔Haemophilus; V
factor (NAD)
Which two enteric organisms are nonmotile? -ANSWER✔✔Klebsiella & Shigella
Voges-Proskauer = Pink; Phenylalanine = No color change
TSI = A/A; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = Yellow
Urea = Pink; Motility = Negative
What is the identification? -ANSWER✔✔Klebsiella pneumoniae
The technologist isolated gram negative diplococci from a sputum specimen. The
following results are obtained:
CHO utilization: glucose =, maltose =, lactose =, sucrose =, nitrate +, DNAse +
What is the identification of the isolate? -ANSWER✔✔Moraxella catarrhalis
QUESTIONS AND ANSWERS WITH
COMPLETE SOLUTIONS (GRADED A+)
Microbiology: Enteric Bacilli Biochemical Identification Matrix
What organism is identified by the following biochemical profile?
Voges-Proskauer: No color change (Negative)
Phenylalanine Deaminase: No color change (Negative)
TSI (Triple Sugar Iron): A/A with {H}_2\ (Acid slant / Acid butt,
Hydrogen Sulfide production)
Citrate: Blue (Positive)
Lysine Decarboxylase: Yellow / Control yellow (Negative)
Indole: No color change (Negative)
ONPG: Yellow (Positive - slow/late lactose fermenter)
Urease: Yellow (Negative)
Motility: Positive
Which organism can cause "traveler's diarrhea" in developing countries? -
ANSWER✔✔E. coli
Which organism is typically MUG positive and what does a positive reaction look
like? -ANSWER✔✔E. coli (not E. coli 0157); fluorescence
Which organisms produce lactose positive colonies on MAC and what is the
expected appearance of the organisms? -ANSWER✔✔E. coli, Klebsiella &
Enterobacter are lactose + & produce red/pink colonies
,Which organism causes most urinary tract infections? -ANSWER✔✔E. coli
Voges-Proskauer = Pink; Phenylalanine = No color change
KIA = A/A; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = Yellow
Urea = Pink; Motility = Positive
DNAse = No clearing
What is the identification? -ANSWER✔✔Enterobacter species
Voges-Proskauer = No color change
Phenylalanine = No color change
Kligler iron agar = Yellow/yellow; Citrate = Green
Lysine = Purple (Control tube - yellow); Indole = Red
ONPG = Yellow; Urea = Yellow; Motility = Positive
What is the identification? -ANSWER✔✔Escherichia coli
Which of the Haemphilus species are NOT normal flora? -ANSWER✔✔H.
ducreyi & H. aegyptius
Which two Haemophilus species require X and V factors for growth? -
ANSWER✔✔H. haemolyticus (hemolytic) & H. influenzae (nonhemolytic)
Which two Haemophilus species require V factor for growth? -ANSWER✔✔H.
parahinfluenzae (nonhemolytic) & H. parahaemolyticus (hemolytic)
, Which two Haemophilus species are porphyrin test positive (fluorescence)? -
ANSWER✔✔H. parainfluenzae (no hemolysis present) & H. parahaemolyticus
(hemolysis)
Which organism causes pinkeye? -ANSWER✔✔Haemophilus aegyptius
Which organism is transmitted sexually and causes a chancroid or soft chancre? -
ANSWER✔✔Haemophilus ducreyi
Which gram negative bacilli satellite around staphylococci on sheep blood agar?
What nutrient is supplied by the staphylococci? -ANSWER✔✔Haemophilus; V
factor (NAD)
Which two enteric organisms are nonmotile? -ANSWER✔✔Klebsiella & Shigella
Voges-Proskauer = Pink; Phenylalanine = No color change
TSI = A/A; Citrate = Blue
Lysine = Purple (Control tube - yellow)
Indole = No color change; ONPG = Yellow
Urea = Pink; Motility = Negative
What is the identification? -ANSWER✔✔Klebsiella pneumoniae
The technologist isolated gram negative diplococci from a sputum specimen. The
following results are obtained:
CHO utilization: glucose =, maltose =, lactose =, sucrose =, nitrate +, DNAse +
What is the identification of the isolate? -ANSWER✔✔Moraxella catarrhalis
