Bacteria Flashcards
Chlamydia
Obligate intracellular pathogen
Transmitted between cells as elementary bodies
Replicate in cells as reticulate bodies
Staphylococcus spp
Gram-positive cocci
S. aureus can colonise meat a room tissue
Causes GI disease via toxin but doesn’t colonise epithelium
Streptococcus spp
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
Neisseria spp
Gram-negative cocci
N. gonn
Corynebacterium spp
Gram-positive rods
C. diphtheria causes respiratory disease
Extensive inflammatory exudate and pseudomembrane in nasopharynx
Clostridium spp
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
Escherichia spp
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
Salmonella spp
Gram-negative rods
Invasive intracellular pathogen causes GI disease
Typhii, causes typhoid fever (replicates in macrophages)
Pseudomonas spp
Gram-negative rods
Aeruginosa: opportunistic bacteria
Form biofilms in lungs of cystic fibrosis patients (alginate polysaccharide)
Bacteroides spp
Gram-negative rods
Vibrio cholerae
Cholera, colonises intestinal epithelium
AB5 toxin
H. pylori
Spiral-shaped, gram -ve causing gastric/duodenal ulcers
Extremely motile
Secrete ureases
Bordetella pertussis
Whooping cough
Damage ciliated epithelium via LPS, pertussis toxin and adenylate cyclase
Yersinia pestis
Bubonic plague: point source from rodents
Pneumonic plague: propagated source from humans
Toxoid vaccines
Diphtheria, tetanus
