Bacteria

Question 1

Chlamydia

Answer 1

Obligate intracellular pathogen
Transmitted between cells as elementary bodies
Replicate in cells as reticulate bodies

Question 2

Staphylococcus spp

Answer 2

Gram-positive cocci
S. aureus can colonise meat a room tissue
Causes GI disease via toxin but doesn’t colonise epithelium

Question 3

Streptococcus spp

Answer 3

Gram-positive cocci
S. pyogenes causes pharyngitis
Produces pore-forming toxins (streptolysins)
Later complications are rheumatic fever and glomerulonephritis
S. pneumoniae colonises nasopharynx
Migrates to lower respiratory tract and causes pneumonia

Question 4

Neisseria spp

Answer 4

Gram-negative cocci

N. gonn

Question 5

Corynebacterium spp

Answer 5

Gram-positive rods
C. diphtheria causes respiratory disease
Extensive inflammatory exudate and pseudomembrane in nasopharynx

Question 6

Clostridium spp

Answer 6

Gram-positive rods
C. difficile causes GI disease, produces toxins & spores
Colonises following broad-spectrum antibiotics
Disrupts tight junctions via releasing toxins which glycosylate GTPases
Can form pseudomembranes

Question 7

Escherichia spp

Answer 7

Gram-negative rods
E. coli - GI disease:
ETEC: colonise via adhesins
EPEC: forms pedestals
EHEC: forms pedestals, shigella-like toxin exacerbates inflammation, 0157 main serotype

Question 8

Salmonella spp

Answer 8

Gram-negative rods
Invasive intracellular pathogen causes GI disease
Typhii, causes typhoid fever (replicates in macrophages)

Question 9

Pseudomonas spp

Answer 9

Gram-negative rods
Aeruginosa: opportunistic bacteria
Form biofilms in lungs of cystic fibrosis patients (alginate polysaccharide)

Question 10

Bacteroides spp

Answer 10

Gram-negative rods

Question 11

Vibrio cholerae

Answer 11

Cholera, colonises intestinal epithelium

AB5 toxin

Question 12

H. pylori

Answer 12

Spiral-shaped, gram -ve causing gastric/duodenal ulcers
Extremely motile
Secrete ureases

Question 13

Bordetella pertussis

Answer 13

Whooping cough

Damage ciliated epithelium via LPS, pertussis toxin and adenylate cyclase

Question 14

Yersinia pestis

Answer 14

Bubonic plague: point source from rodents

Pneumonic plague: propagated source from humans

Question 15

Toxoid vaccines

Answer 15

Diphtheria, tetanus

Question 16

Killed whole cell vaccines

Answer 16

Whooping cough (B. pertussis), cholera

Question 17

Live attentuated vaccines

Answer 17

Typhoid (S. typhii), TB (M. bovis)

Question 18

Purified polysaccharide vaccines

Answer 18

Pneumonia, meningitis (Neisseria)