Test 2 Micro (Ppts 5-6)

  1. Uptake of naked DNA from the environment?
  2. Fred Griffith's experiment proved the principle of_____ and what else?
    Proved the principle of transformation and that DNA is the genetic material.
  3. A temporary physiological state during which transformation can occur
  4. Factors affecting transformation (3)
    • Competence
    • Specificity of DNA uptake
    • Size & state of DNA
    • *DNA quality is not necessarily a factor
  5. Newly emergent types of pneumococcal disease are canceling out what?
    Herd immunity
  6. Which mode of horizontal gene transer requires a vector?
    Transduction (via phage)
  7. Virus that infects bacterial cells?
  8. What determines a phage's tropism?
    Tail fibers
  9. What is a phage's head capside made of?
  10. Types of Phages:
    1)  Which one replciates within host cell leading to lysis?
    2)  Which one integrates into host chromosome and can remain quiescent?
    • 1)  Lytic
    • 2)  Temperate (Lysogenic)
  11. 2 Types of transduction
    • Generalized transduction
    • Specialized transducation
  12. Which type of transduction is caused by packing errors?
    What type of phage mediates this?
    Which genes can be transferred?
    • Generalized transduction
    • Mediated by lytic phage
    • Can transfer any bacterial genes
  13. Which type of transduction is caused by excision errors?
    What type of phage mediates this?
    Which genes can be transferred?
    • Specialized transduction
    • Mediated by lysogenic phage
    • Can only transfer genes adjacent to phage integration site
  14. A property of a bacterial cell caused by the presence of a phage. (ex. E.coli is lysogenic for producing the Shiga toxin)
    Lysogenic Conversion
  15. A phage that no longer can form infective phage particles although parts of it are retained due to a useful trait for the bacterium.
    Defective prophage
  16. Which bacteria make an exotoxin and which make an endotoxin?
    • Exotoxin- Streptococcus
    • Endotoxin- Haemophilus
  17. Non-pathogenic bacteria can infect and replicate, but cause no harm.  What is this called?
    Sub-clinical infection (this can happen in an immune person)
  18. Infecting Dose 50 (ID50)
    The number of organisms needed to infect half of the inoculated individuals.
  19. Lethal Dose 50 (LD50)
    Number of organisms needed to kill half of the inoculated individuals.
  20. Genes on the chromosome that are common to almost all strains.
    Core traits
  21. Genes that some strains have; expain hyper-virulent strains
    Variable traits
  22. Antibodies that target a key virulence factor and thus provide protection from the bacterial disease.
    Protectie Antibodies
  23. Diseases that are always present in a population at low levels.
  24. Disease implies that the disease is occurring much more frequently than normal.
  25. World-wide epidemic
  26. Germiest public place is
    • Gas pump handle
    • (16.6% of cell phones have fecal bacteria)
  27. Organism proven to cause a particular disease.
    Etiologic agent
  28. Koch's Postulates
    • 1)  Must find the organism in all cases, but not in healthy people
    • 2)  Must grow the organism in pure culture
    • 3)  Must use the pure culture to cause an experimental infection
    • 4)  Must isolate the organism in pure culture from the experimentally infected animal
  29. A sero-diagnosis is based on how much of an increase in Ab-titer during an infection
    > or = 4
  30. Therapy that will cover many of the common causes.
    Empiric therapy
  31. Spread of organism past the epithelial cell surface (or into a cell)
  32. Time from acquisition of the organisms to the start of symptoms?
    Incubation period
  33. Time during which there are non-specific symptoms, but can spread the bug
    Prodromal period
  34. Specific signs and symptoms of the disease are present
    Acute illness
  35. Time during which the illness subsides and patient returns to health
    Recovery period
  36. Infections that involve organism that are found in the normal human flora
    Endogenous infection
  37. Hospital acquired infections that are often endogenous infections.
    Nosocomial infections
  38. Organisms that are not part of the human flora
    Exogenous organism
  39. Healthy person who has an exogenous pathogen living in his/her flora
  40. How many people die annually due to healthcare assocaited infections?
  41. 2 Most troublesome bugs in hospital setting?
    S. aureus, C. dificile
  42. Destroy neutrophils and macrophages
  43. Bacteria have a ____ molecule at the end of their pili.
    • Lectin
    • Allow bacteria to bind to a specific sugar (change lectin --> change what they bind to)
  44. Which portion of LPS is toxic?
    Lipid A (due to its branched fatty acids)
  45. Which part of LPS provides antigenicity?
    Core carbohydrate
  46. R-antigen
    No O-side chain on core carb.  Colony appears rough. (Ab to R may help clear antigen)
  47. If O-side chain is present, what does the colony look like? What do you need Ab to?
    • Smooth, round
    • Ab to O antigen is normally protective (but there are tons of Gram-N O side chains so you won't have Abs to all of them)
  48. What part of LPS is needed for maximal virulence?
    O antigen
  49. Which has a shorter outer chain, LOS or LPS?
  50. Endotoxin or exotoxin, which causes fever?
    Endotoxin causes fever (stable up to 60 C)

    Exotoxins typically lack fever
  51. Endotoxin or exotoxin, which requires only nanograms to be lethal?

    Endotoxin requires micrograms to be lethal.
  52. Endotoxin or exotoxin, which one has no toxid available?
  53. Endotoxin or exotoin, which one is made up of proteins?
    What is the other one made up of?
    Exotoxin is made up of proteins.

    Endotoxin is made up of Lipid A and carbs (think LPS).
  54. What do endotoxins bind to on B cells, macrophages, etc?
    CD14, TL4
  55. Endotoxin binds to complement and triggers?
    The alternalte complement pathway
  56. Endotoxin up-regulates expression of ______ on endothelial cells --> _______
    Endotoxin up-regulates clotting factor on endothelial cells --> disseminated intravascular coagulation (DIC).
  57. What is used to test water to make sure it doesn not contain endotoxins?
    Limulus Assay
  58. What determines the potentcey of the LPS?
    Chemistry of fatty acids
  59. Injectosome is encoded by?
    Type 3 Protein Secretion System
  60. Three components of LPS
    • Lipid A
    • Core carbohydrate
    • O-side chain
Card Set
Test 2 Micro (Ppts 5-6)
Transformation, Transduction