BIOL41 Exam 4

  1. Primary way of distinguishing normal flora from pathogenic bacteria isolated from the gut
    lactose fermentation
  2. media used to determine ability to ferment lactose
    phenol red broth
  3. EMB plate
    • eosin methylene blue
    • encourages Gram (-) growth
    • dyed colonies if lactose fermented
    • contains peptone, lactose, sucrose, and eosin Y and methylene blue
  4. phenol red broth
    • differential test
    • distinguishes Enterobacteriacceae from other Gram(-) rods
    • shows fermentation by pH change and gas production

    glucose and sucrose were used in lab
  5. citrate test
    • determines what can live on electron transport chain and Krebs cycle alone
    • citrate as sole C source
    • ammonium phosphate as sole nitrogen source
    • green -> blue : POSITIVE 
    • growth -> citrate being utilized
  6. SIM media
    • Sulfur reduction (black ppt from sodium thiosulfate)
    • Indole production from tryptophan (red layer after Kovacs' reagent -> presence of tryptophanase)
    • Motility (movement from stab location)
  7. 2 enzymes involved in sulfur reduction
    • cysteine desulfurase
    • thiosulfate reductase
  8. enzyme involved in indole production
    tryptophanase (tryptophan -> pyruvate, ammonia, indole)
  9. 6 general categories of API20E test
    • 1) fermentation
    • 2) decarboxylase
    • 3) deamination
    • 4) utilization
    • 5) hydrolytic
    • 6) reduction
  10. How do carb fermentation tests work in the API20E system?
    • pH indicator for acid production from fermentation
    • includes VP test
  11. API20E decarboxylase test
    • pH indicator
    • breakdown of R, K, ornithine
  12. API20E tryptophan deaminase test
    tryptophan -- (tryptophan deaminase)--> product+FeCl3 -> color change
  13. API20E hydrolysis reaction (+4 tests)
    • breakdown with enzyme+water
    • 1) Image Upload 2-gal
    • 2) urease
    • 3) indole
    • 4) gelatinase
  14. positive ONPG test
    bacteria can hydrolyze lactose
  15. indication of positive indole reaction
    bacteria can hydrolyze tryptophan
  16. indication of positive gelatinase reaction
    bacteria can hydrolyze gelatin
  17. nitrate reduction test
    • red : POSITIVE
    • reduces nitrate to nitrite
    • anaerobic

    yellow after Zn : reduces nitrate to N2 gas
  18. sulfate reduction test
    • black : POSITIVE
    • organism reduces sulfur
  19. 4 defining characteristics of an enteric
    • 1) Gram (-) bacilli
    • 2) ferment glucose
    • 3) reduce nitrate
    • 4) oxidase (-)
  20. Enterobacteriaceae represent what % of the normal intestinal flora?
    10%
  21. severity/prevalence of diarrheal diseases
    • 1.5M deaths of children/year
    • 2B cases per year
  22. coliforms
    • lactose fermenters
    • "like E. coli"
    • normal intestinal flora
  23. 5 genera of coliforms
    • 1) Escherichia
    • 2) Enterobacter
    • 3) Klebsiella
    • 4) Serratia
    • 5) Citrobacter
  24. prototypical coliform
    E. coli
  25. O in E. coli O157:H7
    outer antigen
  26. H in E. coli O157:H7
    flagellar protein
  27. E. coli O157:H7
    • dangerous pathogen with virulence plasmids
    • causes hemorrhagic colitis, hemolytic uremic syndrome
    • damage due to toxin produced
  28. 3 genera within Enterobacteriaceae that are obligate pathogens
    • 1) Salmonella
    • 2) Shigella
    • 3) Yersinia
  29. 2 major diseases caused by Salmonella
    • 1) typhoid fever
    • 2) gastroenteritis (diarrhea)
  30. 2 major diseases caused by Shigella
    • 1) dysentery
    • 2) gastroenteritis?
  31. major diseases caused by Yersinia enterocolitica and Yersinia pseudotuberculosis
    • 1) gastroenteritis
    • 2) tuberculosis-like sickness
  32. Yersinia pestis
    • causes bubonic plague
    • spread by flea bites
  33. 3 groups classified by temperature requirements
    • 1) thermophiles
    • 2) mesophiles
    • 3) psychrophiles
  34. sterilize vs disinfect
    all dead vs all dangerous dead
  35. 3 most difficult to kill organisms
    • 1) endospores
    • 2) mycobacteria
    • 3) protozoan cysts
  36. What happens when a cell is subjected to heat?
    proteins are denatured
  37. thermal death time
    how long it takes to get the microbe # to 0 at a certain T
  38. dry vs moist heat
    • dry heat takes longer, requires higher T
    • moist heat takes lower T, & is more penetrating
  39. boiling
    only kills vegetative cells
  40. autoclave
    • sterilizes
    • kills all but prions
  41. Pasteurization
    kills some bacteria & viruses but not all
  42. dry heat oven
    can sterilize, but takes longer, with higher T
  43. incineration
    burns all organisms to ash
  44. dessication
    drying so microbes don't grow
  45. lyophilization
    freeze-drying
  46. leukocytes
    WBCs
  47. 5 types of peripheral blood WBCs
    • 1) neutrophil
    • 2) basophil
    • 3) eosinophil
    • 4) monocyte
    • 5) lymphocyte
  48. 3 types of granulocytes
    • 1) neutrophils
    • 2) basophils
    • 3) eosinophils
  49. 2 types of agranulocytes
    • 1) monocytes
    • 2) lymphocytes
  50. neutrophil (appearance, fcn, %)
    • segmented lobes of nucleus, neutral-staining granules
    • phagocytize bacteria
    • 55-65%
  51. eosinophil (appearance, fcn, %)
    • 2 lobes in nucleus, granules stain red
    • allergic, parasitic reactions
    • 1-3%
  52. basophil
    • dark staining granules
    • similar to mast cells, inflammatory response
    • 0.5-1%
  53. monocyte (appearance, fcn, %)
    • largest of leukocytes, horseshoe-shaped nucleus
    • blood form of macrophages (phagocytosis)
    • 3-7%
  54. lymphocyte (appearance, fcn, %)
    • spherical nucleus that takes up most of the cell
    • specific acquired immunity (T/B cells)
    • 25-33%
  55. elevated neutrophil count
    bacterial infection
  56. elevated eosinophil count
    parasitic infection
  57. 5 non-specific defenses of eyes
    • 1) tears (mech)
    • 2) blinking (mech)
    • 3) salt (chem)
    • 4) lysozyme (chem)
    • 5) peptides (chem)
  58. trachoma
    • most common eye infection
    • leading cause of blindness
    • repeated infections cause scarring that scratches cornea
  59. ophthalmia neonatorum
    swelling (inflammation) or infection of the tissue lining the eyelids in a newborn
  60. antigen
    substance that evokes the production of one or more antibodies
  61. epitope
    the part of an antigen that is recognised by the immune system
  62. K antigen
    bacterial capsular antigen, a surface antigen external to the cell wall
  63. O antigen
    one occurring in the lipopolysaccharide layer of the wall of gram-negative bacteria
  64. H antigen
    • 1. a bacterial flagellar antigen important in the serological classification of enteric bacilli.
    • 2. the precursor of the A and B blood group antigens; normal type O individuals lack the enzyme to convert it to A or B antigens.
  65. antibody
    Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses
  66. Fab region
    • fragment antigen-binding
    • region on an antibody that binds to antigens
    • composed of one constant and one variable domain of each of the heavy and the light chain
  67. Fc region
    • fragment crystallizable region
    • tail region of an antibody that interacts with cell surface receptors
    • allows antibodies to activate the immune system
    • composed of two identical protein fragments, derived from the second and third constant domains of the antibody's two heavy chains
  68. immunoassay
    specific type of biochemical test that measures the presence or concentration of a substance in solutions that frequently contain a complex mixture of substances
  69. serology
    study of blood serum and other bodily fluids
  70. precipitation reaction
    occur between soluble antigens and homologous antibodies precipitate forms when the two are at concentrations that allow maximum crosslinking in the antigen–antibody complex that forms
  71. immunodiffusion assay
    In one well is the antiserum; in the other is the sample with unknown antigen composition. The two diffuse out of their respective wells toward each other. If the sample has an antigen that will react with the antibody, then a precipitation line will form at the region of optimal proportions as their diffusion paths pass.

    If no precipitation line forms, the test is considered negative. That is, the sample has no antigen that will react with the antibodies.
  72. agglutination reaction
    Particulate antigens (such as whole cells) may combine with homologous antibodies to form visible clumps (agglutinates)

    used for blood typing
  73. ELISA
    Enzyme Linked ImmunoSorbant Assay

    • 1) specific Ag coated onto wells, unbound washed off, well blocked
    • 2) sample w/ unknown Ab added to wells
    • 3) secondary Ab added to react with primary Ab, unbound washed off
    • 4) substrate added to react w/ secondary Ab (peroxidase) for color change
Author
daynuhmay
ID
187130
Card Set
BIOL41 Exam 4
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BIOL41 Exam 4
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