Bacillus & Listeria

Question 1

1. What is the morphology of bacilli microscopically?
2. What is the gram stain of bacilli?

Answer 1

1. Rods
2. Positive

Question 2

True or false:

Bacilli have spores.

Answer 2

True

Question 3

What is this organism?

Answer 3

Bacillus anthracis

Question 4

What type of hemolysis does Bacilli use?

Answer 4

NONE

Question 5

What does the Bacillus toxin bind to?

Answer 5

Protective antigen

Question 6

What are the 2 incubation areas for Bacillus anthracis?

Answer 6

1. Consistent alternation between wet and dry
2. Soil high in nitrogen

Question 7

How does Bacillus anthracis affect cattle?

Answer 7

Septicemia, toxemia, and death

Question 8

How does Bacillus anthracis affect sheep?

Answer 8

Septicemia, toxemia, death

Question 9

How does Bacillus anthracis affect horses?

Answer 9

Colic, edema of the head, neck, & shoulders

Question 10

How does Bacillus anthracis affect swine?

Answer 10

Affects pharyngeal region

Question 11

How does Bacillus anthracis affect dogs and cats?

Answer 11

Affects pharyngeal region

Question 12

How can Bacillus anthracis affect a human being?

Answer 12

1. Respiratory infection
2. Malignant carbuncle
3. Gastroenteritis

Question 13

How did human beings become infected with Bacillus anthracis?

Answer 13

1. Woolsorting
2. Making drums/hides

Question 14

Which species of Bacillus is penicillin suseptible?

Answer 14

Anthracis

Question 15

How might you diagnosis Bacillus anthracis?

Answer 15

1. Ear slice
   
   • Do an impression smear
2. Culture
   
   • Typical colonies
   • Penicillin suseptibility
3. PCR

Question 16

1. What type of immunizing agents are there for animals?
2. What about for humans?

Answer 16

1. Modified live
2. Killed strain

Question 17

1. How often must you get revaccinated?
2. When does immunity typically wane?

Answer 17

1. Anually
2. Every 6 months

Question 18

What are your drugs of choice in treating Bacillus anthracis in an animal?

Answer 18

1. Penicillin
2. Tetracyclin

Question 19

How might an infection with Bacillus cereus be acquired?

Answer 19

Food poisoining

Question 20

What might predispose an individual to a Bacillus subtilis infection?

Answer 20

1. Heroin use
2. Immunocomprimised

Question 21

What problems can Listeria monocytogenes cause in a ruminant?

Answer 21

1. Abortion
2. CNS disease

Question 22

What is the morphology of Listeria microscopically?

Answer 22

Gram positive flat rod (coccoidal)

Question 23

How many toxins make up Bacillus anthracis?

What are they?

Answer 23

1. Protective antigen
2. Edema factor
3. Lethal factor

Question 24

Which toxins of Bacillus anthracis act as A-subunits?

Answer 24

1. Edema factor
2. Lethal factor

Question 25

How does edema factor work in Bacillus anthracis?

Answer 25

Activates adenylate cyclase and interferes with cell function

Question 26

How does the lethal factor work in Bacillus anthracis?

Answer 26

Proteolyticly cleaves the kinase involved in signal transduction in CD4+ T lymphocytes and fibroblasts. It inhibits IL-2 production and proliferative responses in the CD4+ T cells. Cleavage of the MAPK kinase in fibroblasts is apparently lethal to those cells.

Question 27

What is the capsule of Bacillus anthracis composed of?

Answer 27

Poly-D-glutamic acid

Question 28

To be affective, what must the Bacillus anthracis vaccine have in it?

Answer 28

Protective antigen

Question 29

1. Which animals does Listeria monocytogenes affect? 2. What problems does it cause in each of these species?

Answer 29

1. Cattle & sheep 2. CNS problems in cattle and sheep; abortions in sheep

Question 30

What type of hemolysis does Listeria monocytogenes use?

Answer 30

Narrow zone BETA hemolysis

Question 31

List the laboratory results for Listeria monocytogenes in the following tests: 1. H₂S 2. Catalase 3. Litmus milk 4. Motility

Answer 31

1. H2S = negative 2. Catalse = positive 3. Litmus milk = rapid reduction 4. Motility = at 22EC by peritrichous flagella

Question 32

What is this organism?

Answer 32

Listeria monocytogenes

Question 33

1. In what pH does L. monocytogenes replicate? 2. At which pH should silage be kept because of this?

Answer 33

1. 5.5 - 9.0 2. Below 5

Question 34

List ubiquitous places for L. monocytogenes to be found?

Answer 34

1. Soil 2. Intestinal tracts (herbivores) 3. Feces 4. Silage 5. Plant material 6. Milk

Question 35

Explain in detail how L. monocytogenes gets away from humoral immune responses in the body?

Answer 35

* Organism is ingested by a macrophage * Listeriolysin O destructs the phagosome * Listeris is released into the cytosol * Surrounded by actin-like filaments from the host cell * This structure forms a tail * Facilitates movement to the cell membrane of macrophage * Cell membrane evaginates * Organism transfered to another macrophage * Being an intracellular parasite, is NOT susceptible to killing by (1) antibody or (2) complement

Question 36

Listerolysin O allows Listeria to be what type of parasite?

Answer 36

Falcultative intracellular parasite

Question 37

What affects does L. monocytogenes have on cattle?

Answer 37

1. Circling disease * Unilateral facial paralysis * Fever * Blindness * Head pressing * Death 2. Abortion * Establishes a bacteremia or septicemia and localizes in the placentomes - that causes the death of the fetus

Question 38

What affect does L. monocytogenes have on sheep and goats?

Answer 38

Same as in cattle: Circling disease Abortions

Question 39

What affect does L. monocytogenes have on monogastrics / young ruminants?

Answer 39

1. Septicemia 2. Focal necrosis of the liver, spleen, LN

Question 40

What might be your drugs of choice in treating L. monocytogenes?

Answer 40

1. Ampicillin 2. Tetracyclin 3. Penicillin