0317 - Bacteria in the Body - EG

Question 1

What virulence factor plays a key role in gaining entry?

Answer 1

ahesins - coordinate binding of the organism to a host tissue

Question 2

List some virulence factors of bacterial pathogens.

Answer 2

adhesins
invasins
impedins
aggressins
modulins

Question 3

List some host molecules that act as receptors for bacterial adhesins and the type of interactions they form.

Answer 3

Host Receptors:

• glycoproteins, glycolipids, phospholipids
• ECM
• transmembrane proteins
• receptors for cytokines/hormones

Types of binding:

• hydrophonic interactions
• cation bridging
• specific ligand-receptor interaction

Question 4

What bacterial factors are involved in adhesion?

Answer 4

Gram +'ve -'ve:
- polysaccharides
Gram +'ve:
- lipotechoic acid
- cell wall peptidoglycan
Gram -'ve:
- lipopolysaccharide
- flagella

Question 5

List some mechanisms of dissemination of bacterial pathogens.

Answer 5

• physical trauma
• inter- and intra- cellular spread
• infection of macrophages and spread through lymphatics
• haematogenous spread
• local and systemic release of bacterial toxins