Major Mechanisms of Pathogenicity

Question 1

colonization is a way for a bacteria to be forced into an environment and is important for adherence and partial adherence.

What are structures that help adherence in gram positive and gram negative organisms?

Answer 1

pilli/fimbriae (gram negative)

teichoic acids (gram positive)

adhesions (pertussis toxin and hemagglutins)

IgA proteases ( to attach to mucosal surfaces)

Question 2

what structure can give partial adherence to inert materials

Answer 2

biofilms (slime laters which give resistance and act as tight connections between bacteria through glycoproteins)

Question 3

bacteria with a capsules have anti _ properties

what are the most common encapsulated organisms

Answer 3

antiphagocytic

Please SHINE my SKiS

pseudomonas, streptococcus pneumonia, haemophilus, neisseria, e. coli , salmonella, klebsiella, step (group B)

Question 4

what fungus is encapsulated

Answer 4

cryptococcous neoformans

Question 5

surface components are also anti-phagocytic along with capsules

surface component of s. pyogenes:

surface component of N. gonorrhea:

surface component of S. Aureus:

Answer 5

surface component of s. pyogenes: M protein

surface component of N. gonorrhea: pili

surface component of S. Aureus: A protein

Question 6

what is antigenic variation

Answer 6

change in surface antigens to avoid immune detection

Question 7

antigenic variation in gonorrheae:

Answer 7

change in pill and outer membrane proteins

Question 8

antigenic variation in T. Bruce rhodesiense and T. Bruce gambiense:

Answer 8

phase variation

Question 9

antigenic variation in enterobacteriaceae:

Answer 9

capsular and flagellar antigens

Question 10

antigenic variation in HIV and influenze:

Answer 10

antigenic drift

Question 11

variations in HIV

Answer 11

gp120 and gp40

Question 12

variations in influenzae

Answer 12

neurominadase
hemagluttanin

Question 13

how can bacteria survive intracellularly

Answer 13

evasion of intracellular killing, invasions, damage secondary to intracellular replication

Question 14

M tuberculosis has _ that inhibit phagosome-lysosome fusion

Answer 14

sulfatides

Question 15

listeria monocytogenes escapees from the _ before phagosome-lysosome fusion

Answer 15

phagosome

Question 16

Yersinia pseudotuberculosis surface proteins allow organisms to bind to and infect normally _ _ cells

Answer 16

non-phagocytic cells

Question 17

examples of ways bacteria damage cells secondarily to intracellular replication

Answer 17

lysis, transformation, and latency

Question 18

what is molecular mimicry

• results in immune mediated damage/inflammation from bacteria

Answer 18

cross reaction of bacteria induced antibodies with tissue antigens (like in rheumatic fever)- type two hypersensitivity

Question 19

delayed hypersensitivity and granulomatous response is usually triggered by _ (intracellular/extracellular) bacteria or systemic _

Answer 19

intracellular

mycoses

Question 20

granulomatous response and delayed hypersensitivity is a type _ HSR

Answer 20

4

Question 21

large fragments of _ can cause immune mediated damage or inflammation. They work as structural toxins that are released from gram + organisms and serve as chemoattractants for _

Answer 21

peptidoglycan-teichoic acid

neutrophils

Question 22

toxins aid in invasion, damage cells and inhibit cellular processes or trigger an immune response and damage. What are the 2 types of toxins?

Answer 22

structural toxins and exotoxins

Question 23

structural toxins are found within the _ of gram positive and gram negative bacteria

Answer 23

envelope

Question 24

exotoxins are _ toxins secreted into the environment by gram positive and gram negative bacteria

Answer 24

protein