Pseudomonas CF L6

Question 1

What is the physical characteristic of Pseudomonas Aeruginosa?

Answer 1

Gram -
Highly motile
Rod Shaped Bacteria

Question 2

What does Pseudomonas Aeruginosa use for respiration and oxidative metabolism?

Answer 2

Oxygen

Question 3

What are some characteristic of Pseudomonas Aeruginosa?

Answer 3

• Binds tightly to lung epithelium
• Can grow anaerobically by fermentation
• Produces extracellular polysaccharide (mucoidy)
• PRIMARY CAUSE OF DEATH FOR CF PATIENTS

Question 4

Define characteristics of Gram +

Answer 4

• Thick PG layer
• No Outer Membrane
• No lipopolypeptide

Question 5

Define charateristics of Gram -

Answer 5

• Thin PG layer
• Outer membrane
• Lipopolypeptide

Question 6

What consists of the inner leaflet of the outer membrane and what is its function?

Answer 6

Phospholipids

-Barrier to hydrophilic compounds

Question 7

What consists of the outer leaflet of the outer membrane and what is its function?

Answer 7

Lipopolysaccharide

• Negatively charged
• Resistant to detergents and other hydrophobic molecules

Question 8

What is on the outer membrane that allows entry of small molecules?

Answer 8

Pores

-let in small hydrophilic molecules

Question 9

What is LPS?

Answer 9

• AKA: endotoxin

- Potent antigen

Question 10

What does LPS cause? (2)

Answer 10

1. Strong adaptive immune response

2. Strong innate immune response

Question 11

With LPS, what is an example of a strong adaptive immune response?

Answer 11

Stereotyping strains like E. coli O157:H7

Question 12

With LPS, what is an example of a strong innate immune response?

Answer 12

• Cytokine production

- Septic shock

Question 13

What is flagellum?

Answer 13

Most common agent of motility

Question 14

What is motility?

Answer 14

Allows bacteria to penetrate mucous layer

Question 15

What is chemotaxis?

Answer 15

-movement towards food or away
from poisons.
-Specific receptors on
bacterial cell surface direct motility.

Question 16

How does a bacterium know when and where it should swim?

Answer 16

Bacterial chemotaxis and motility are controlled by a 2-component regulatory system

Question 17

What consists of the two component regulatory system?

Answer 17

1. Sensor histadine kinase (SHK)

2. Resonse regulator

Question 18

What are adhesins?

Answer 18

Bind to sugars and proteins on the host cell surface

Question 19

Where are adhesins found?

Answer 19

Microbial cell surface

Question 20

T/F Adhesins can be specific

Answer 20

True

Question 21

Name some potential adhesive structures for bacteria

Answer 21

1. Pili
2. Flagella
3. Capsules

Question 22

What are capsules?

Answer 22

• Loose network of polymers surrounding cells

- Polysaccharide or protein or both

Question 23

What is the role of the capsule?

Answer 23

1. Adherence
2. Protection against phagocytosis
3. Protection against some environmental stresses

Question 24

Name the important encapsulated pathogens (4)

Answer 24

1. Streptococcus Pneumonia
2. Haemophilus influenza
3. Neisseria meningitidis
4. Pseudomonas aeruginosa

Question 25

What is alginate?

Answer 25

• It produces the mucoidy that CF patients have

- A protective capsule

Question 26

What does the production of alginate depend on?

Answer 26

AlgU, a sigma factor

Question 27

State process of AlgU

Answer 27

1. AlgU normally held in an inactive state by interaction with MucA
2. When cell senses cell wall stress, MucA is degraded by proteases –> activated AlgU
3. AlgU directs transcription of the Alginate gene

Question 28

What do CF patients have a lot of alginate?

Answer 28

INACTIVE MUCA

Question 29

What are the signaling compouns?

Answer 29

1. Acylated homoserine lactones (Gram - )

2. Peptides (Gram +)