Bacillis - Exam 2

Question 1

Which species of Bacillus is the only consistent pathogen of vertebrates?

Answer 1

B. anthracis

Question 2

Bacillis is catalase _________, and is important in distinguishing it from which other bacteria?

Answer 2

Catalase positive

Catalase production important to distinguish from Clostridia

Question 3

When does Bacillus form spores?

Answer 3

When subjected to stress, for protection

Question 4

True/False. A spore always needs to form a capsule.

Answer 4

False! It does not!

Question 5

What are the plasmids that are important virulence factors and regulatory genes?

Answer 5

pX01 and pX02

Question 6

What does the plasmid pX01 contain?

Answer 6

AtxA (Anthrax toxin activator)

AcpA (Anthrax capsule activator)

Gene for edema and lethal toxin

Question 7

What does the plasmid pX02 contain?

Answer 7

Gene for encoding the capsule

Question 8

Which form of Bacillis produces a capsule?

Answer 8

Vegetative form

Question 9

What is the capsule of Bacillis composed of?

Answer 9

D-glutamyl polypeptide

Question 10

Which type of Bacillis isolates are used for vaccines?

Answer 10

Non-encapsulated isolates because they are avirulent

Question 11

What is lethal toxin composed of?

Answer 11

Protective antigen (responsible for binding target cells)

and

Lethal factor (responsible for toxicity)

At low doses causes a cytokine “storm” leading to multi-organ disfunction

At higher concentrations produces apoptosis of macrophages

Question 12

What is edema toxin composed of?

Answer 12

Protective antigen (responsible for binding to target cells)

and

Edema factor (causes electrolyte and fluid loss in affected cells)

Question 13

What are the two effects of the edema factor?

Answer 13

EF will either kill macrophages or cause edema in tissue

Question 14

Calcium in combination with __________, allows the spore to survive decades in a dry environment.

Answer 14

Dipicolinic acid

Question 15

Which species is almost totally resistant to Bacillis anthracis?

Answer 15

Birds

Question 16

What is the main reservoir for Bacillis anthracis?

Answer 16

Soil and water

(herbivores are most susceptible)

Question 17

How is Bacillis transmitted and what is the infectious unit?

Answer 17

Infections takes place by:

1. Ingestion of contaminated feed or water
2. Via wound infection and arthropod bits

Infectious unit is the endospore

Question 18

What are the most susceptible species to Bacillis anthracis and what does it cause?

Answer 18

RUMINANTS! (cattle and sheep)

SEPTICEMIA! (and bleeding at body orifices)

Question 19

True/False. Rigor mortis is often absent with infection of Bacillis?

Answer 19

True

Question 20

What does Bacillis anthracis cause in horses?

Answer 20

Colic and diarrhea

Edema mainly in point of infection

Septicemia

Question 21

What tissue is typically infected with Bacillis in swine?

Answer 21

Pharyngeal tissue

Question 22

What are the three types of anthrax in humans?

Answer 22

Cutaneous anthrax

GI anthrax

Pulmonary or inhalation anthrax

Question 23

True/False. Bacillis anthracis can contaminate the soil after the animal it was infecting has died.

Answer 23

True

Question 24

True/False. You should perform a field necropsy on animals suspected of dying from Bacillis anthracis?

Answer 24

FALSE! NO FIELD NECROPSY!!!!!!!!!

Question 25

What stain is used to ID Bacillis anthracis?

Answer 25

McFadyean's methylene blue

Question 26

What is the main treatment for Bacillis anthracis?

Answer 26

Antimicrobial treatment with antiserum

Question 27

Which type of Bacillis is associated with abortion and bovine mastitis?

Answer 27

Bacillis cereus

Question 28

Which type of Bacillis is associated with food spoilage?

Answer 28

B. licheniformis

Question 29

True/False. Bacillis is a reportable disease.

Answer 29

TRUE

Question 30

True/False. Bacillis is an obligate anaerobe.

Answer 30

FALSE. Bacillis is a facultative anaerobe