MIDTERMS: L4 - GRAM-POSITIVE BACILLI

Question 1

Occurs in long chains, bamboo-rod appearance

Answer 1

Bacillus anthracis

Question 2

MOTF
Capsule (poly-D-glutamic acid) - encoded in plasmid
pXO2

Anthrax toxin - Encoded on plasmid pXO1

Answer 2

BOTH TRUE

Question 3

MOTF
1. Protective antigen - allows entry of lethal factor and edema factor
2. Lethal factor - Acts as adenylate
cyclase which increases the host cell’s CAMP
3. Lethal factor - major virulence factor, a zinc metalloprotease that inactivates protein kinase causing death

Answer 3

1,3 - true

2 - Edema factor

Question 4

MOTF

1. Most common anthrax - Cutaneous anthrax
2. Most severe - pulmonary anthrax

Answer 4

1 true, 2 false

2 - GIT anthrax

Question 5

Characterized by localized small erythematous papule which progresses to a ring of vesicles into ulceration called black eschar

Answer 5

Cutaneous anthrax

Malignant pustule (black eschar)

Question 6

Woolsorter’s disease or ragpicker’s disease

Answer 6

Pulmonary anthrax

Question 7

Removes contaminating organisms in solid media

Answer 7

heat or alcohol shock

62-65°C for 15-20 mins for B. anthracis

Question 8

Rapid presumptive immunochromatographic test that identifies B. anthracis within 15 minutes

Answer 8

Red line alert test

Question 9

B. anthracis appear as beaten egg whites in what plate:

A. BAP
B. PLET: polymyxin B lysozyme EDTA Thallous Acetate Agar
C. GELATIN

Answer 9

B. PLET: polymyxin B lysozyme EDTA Thallous Acetate Agar

Question 10

irregular fringe-like margin with curled or
swirling projections MEDUSA HEAD/ LION
HEAD/ COMET TAIL

Answer 10

Bacillus anthracis

Ground glass colonies

Question 11

B. anthracis appear as _____ in GELATIN

A. Medusa Heads
B. Inverted pine tree
C. Ground glass

Answer 11

B.

Question 12

Anthrax drug of

choice

Answer 12

Intravenous (IV) Ciprofloxacin

Question 13

ALL ARE CORRECT EXCEPT:
Bacillus cereus
1. Gram positive
2. Spore forming
3. Non-motile
4. Encapsulated
5. Beta-hemolytic

Answer 13

3,4

BC are motile, non-encapsulated

Question 14

1. B. cereus cause short incubation type of food poisoning
2. Emetic - fried rice
3. Nausea and vomiting

Answer 14

Emetic

Question 15

1. Long incubation type food poisoning
2. Meat
3. Diarrhea

Answer 15

Diarrheal

Question 16

Referred as hemolysin 4

Answer 16

Cytotoxin K

Question 17

MOTF

1. Enterotoxin - heat labile
2. Emetic - heat stable

Answer 17

BOTH TRUE

Question 18

B. cereus heat shock treatment

Answer 18

70°C for 30 mins 80°C for 10 mins

Question 19

T OR F

B. cereus appear as feather colonies and ground glass appearance

Answer 19

False

Frosted glass appearance

Question 20

1. Used as insecticide or pesticide to control
   insects such as moth, beetles, flies
2. Posses cellulite enterotoxin

Answer 20

B. thuringiensis

Question 21

Clostridium botulinum
- Blocks release of acetylcholine from the
presynaptic nerve terminals in the autonomic nervous system and motor end plates resulting in flaccid paralysis

Answer 21

Botulism Toxin

Question 22

Subterminal spores that resemble TENNIS

RACKET appearance

Answer 22

Clostridium botulinum

Question 23

SELECT TRUE FOR 
Clostridium botulinum
1. Gram-negative
2. Tennis racket appearance
3. Aerobic
4. Beta hemolytic (except for type G)
5. Subterminal spores
6. Boxcar appearance

Answer 23

2,4,5

1 - gram positive
3 - strict anaerobic

Question 24

ALL TRUE EXCEPT FOR:
Clostridium tetani
1. Tack head bacillus
2. Terminal spore
3. Peritrichous flagella
4. Swarming colonies
5. Non-hemolytic
6. Ferment carbohydrates

Answer 24

5,6

5 - beta hemolytic
6 - Does not ferment any carbohydrates

Question 25

Blocks inhibitory neurotransmitters (glycine,GABA)

Answer 25

Tetanospasmin

Question 26

Gas Gangrene bacillus

Answer 26

Clostridium perfringens

Question 27

ALL ARE TRUE FOR Clostridium perfringens except: 1. Non-capsulated 2. Non-motile 3. No spores in ordinary media 4. target/double zone of hemolysis 5. Boxcar appearance 6. Chopped-Meat glucose positive

Answer 27

1 - encapsulated

Question 28

Most important toxin of C. perfringens - mediate destruction of cell membranes

Answer 28

Alpha toxin

Question 29

MOTF C. perfringens 1. CAMP test - Bowtie 2. Reverse CAMP - arrowhead

Answer 29

BOTH TRUE

Question 30

MOTF Clostridium difficile 1. Motile 2. Non-encapsulated

Answer 30

BOTH TRUE

Question 31

MOTF Clostridium difficile Toxin A - potent cytotoxin Toxin B - Potent enterotoxin; weakly cytotoxic

Answer 31

BOTH FALSE Toxin B - potent cytotoxin Toxin A - Potent enterotoxin; weakly cytotoxic

Question 32

``` CAA (choose all apply) Clostridum difficile 1. Oval and subterminal spore 2. Non-hemolytic on BAP 3. Horse manure odor in CCFA 4. Exhibits chartreuse characteristics ```

Answer 32

1,2,3,4

Question 33

``` CAA Corynebacterium diphtheriae 1. Acid fast 2. Motile 3. Spore-forming 4. Klebs-Loeffler bacillus 5. Gram positive 6. Club-shaped ```

Answer 33

4,5,6 1. Non-af 2. Non-motile 3. Non-spore

Question 34

Possess the metachromatic granules called | Babes-Ernst granules

Answer 34

Corynebacterium diphtheriae

Question 35

Cervical and submandibular lymphadenopathy causing the “bull neck” appearance

Answer 35

Corynebacterium diphtheriae

Question 36

Can also be performed for the better visualization of the organism’s typical Chinese letter appearance

Answer 36

Loeffler’s MB

Question 37

Cornybacterium diptheriae in Modified Tinsdale Agar and Cystine Tellurite Blood Agar appear as:

Answer 37

Brown-black colonies with halo

Question 38

``` CAA Corynebacterium diphtheriae 1. Catalase positive 2. Oxidase positive 3. Urease negative 4. Oxidase negative 5. Ferment glucose and maltose, not sucrose 6. Catalase negative ```

Answer 38

1,2,3,5

Question 39

- Carry tox gene - Bovine Mastitis A. C. ulcerans B. C. pseudotuberculosis C. C. minutissimum

Answer 39

A. C. ulcerans

Question 40

- Suppurative granulomatous lymphadenitis A. C. ulcerans B. C. pseudotuberculosis C. C. minutissimum

Answer 40

B. C. pseudotuberculosis

Question 41

``` CAA Listeria monocytogenes 1. Non - acid fast 2. Non spore forming 3. Facultative anaerobe 3.Tumbling motility - 22-28 degree celcius 4. Umbrella - semi-solid media 5. Catalase negative 6. Esculin hydrolysis positive ```

Answer 41

1,2,3,4,6 5 - catalase positive

Question 42

Major virulence factor of L,monocytogenes

Answer 42

Listeriolysin | O:

Question 43

``` CAA Erysipelothrix rhusiopathiae 1. Catalase positive 2. Non-motile 3. No capsule 4. Microaerophilic 5. Alpha hemolytic 6. Serovar 1 and 2 - human infection 7. H2s positive ```

Answer 43

2,3,4,5,6,7 1 - catalase negative

Question 44

Chalky, dry, crumby colonies in SDA

Answer 44

Nocardia

Question 45

Molar tooth colonies

Answer 45

Actinomyces

Question 46

Implicated in acne vulgaris, endocarditis, shunt infections

Answer 46

Propionibacterium acnes