Test 1 Flashcards
Used to stain polysaccharide capsules
India ink stain
Used to stain organisms that are characterized by waxlike nearly impermeable cell walls; they contain mycolic acid and large amounts of fatty acids, waxes, and complex lipids.
Acid Fast stain
What does a KOH prep do?
Lyses Gm- and does not lyse Gm+. It’s a way to determine if its Gm- or Gm+ fast.
The scientific study or diagnostic examination of blood serum, especially with regard to the response of the immune system to pathogens or introduced substances.
Serology
Bacteria are prokaryotic cells, and as such they contain no membrane- bound organelles True or false?
True
a major virulence factor, found in the outer membrane of gram- bacteria
Lipopolysaccharide (LPS)
peptidoglycan is constantly be synthesized and degraded by…
autolysins
‘spot-weld’ these ‘girders’ into place by cross-linking the peptides hanging from the girders to peptides dangling from the existing wall.
transpeptidases
LPS comes in contact to MO and Platelets, they then activate…
MO:
TNF-a»_space;> NO-»> Dilates BV
PEG-2»_space;> osteoclasts
Collegians»_space;> Collagen fibers destroyed
Platelets:
Fibrinogen active»_space;> IV Coagulation»_space;> Clotting
DNA is ‘slurped’ up from a nearby dead cell by a live bacteria cell
Transformation
Viruses transfer DNA between bacteria
Transduction
DNA is directly passed from one bacterium to another
Conjugation
causes the capillary endothelial cells to show ‘stop signs’ that cause certain inflammatory response cells to exit the capillaries and move to the site of injury.
cell adhesion molecules, or CAMs
Primary Lymphatic tissue includes
The bone marrow and Thymus
Secondary lymphatic tissue includes
Adenoids Tonsils Appendix Payer's P. Lymph nodes Spleen
small region of the antigen that actually binds to a B or T cell antigen recognition receptor
epitope
All gram-negative bacteria have________, and often have one or more __________.
endotoxins
exotoxins
Gram-positive bacteria do not have__________, but often have one or more_________.
endotoxins
exotoxins
LPS itself activates:
• Complement cascade (alternative pathway), which initiates inflammation
• Hageman factor (causing coagulation!)
• Platelets (causing coagulation!)
• Macrophages/monocytes (causing secretion of pro inflammatory
mediators, enzymes and O2-radicals)
What does the B Protein do in A-B toxin?
B protein component binds the A-B toxin specifically to certain host cells
What does the A Protein do in A-B toxin?
A unit enters the cell as an enzyme and
damages certain cell functions
What is ribosylation?
A-B toxins use NADH to add ribose to host
proteins such as elongation factor (blocking protein synthesis)
What does A-B Shiga-toxin Do?
cleave ribosomal RNA, blocking ribosome function and thus inhibit protein synthesis.
Superantigens Do what?
Inappropriately bind the Th cell TCR to HLA-II
molecule on APCs, initiating Th cell/macrophage activation, and a hugely excessive cytokine production
S. Pyogenes Major characteristics
Acts opportunistically, found in the back of the throat
b-Hemolytic, Group-A
Many Toxins (exo)
May cause Strep Throat, rheumatic fever, cellulitis
S. Agalactiae Major characteristics
Found in GI or vaginal mucosa
b-Hemolytic, Group-A
Capsule
Can cause Neonatal sepsis
S. pneumoniae Major characteristics
Found in throat
a-Hemolytic
Capsule
Can cause Pneumonia, earinfections»>Meningitis
Verdans Strep group Major characteristics
a-hemolytic
Causes Endocarditis, caries
S. Pyogenes M Protein and F Protein are used for?
Facilitating colonization M Protein F Protein (fibronectin-binding protein) cross-link pili to host fibronectin on host epithelial cells
Released by S. Pyogenes, inactivates ‘911’ molecule,
and thus interferes with alerting immune cells.
C5a peptidase
Second most common cause of Urinary tract infections in young women.
• S. saprophyticus
Staphylococcus aureus component of the cell wall. It binds to the Fc of IgG, thus blocking Ab opsonization
Protein A
Staph. aureus are notorious for causing abscess diseases. How does he do it?
within a ‘fibrin fort,’ produced by the action of coagulase
causes the very serious Toxic Shock Syndrome.
Toxic shock syndrome toxin (TSST-1) – superantigen
Nosocomial infections are?
hospital acquired infections.
Iatrogenic infections are?
Doctor acquired infections.
