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Flashcards in Micro High Yield Deck (102):
1

What is the component of the cell wall leads to induction of TNF and IL-1?

Lipoteichoic acid

2

What is the major surface antigen of the outer membrane of gram negative bactiera?

LPS (Lipid A induces TNF and IL-1, O polysaccharide is the antigen)

3

What is contained within the perilasmic space?

hydrolytic enzymes (including beta lactamases)

4

What makes spores resistant to dehydration/ heat and chemicals?

Keratin- like coat, dipicoliinic acid and peptidoglycan

5

What 6 types of "bugs" do NOT gram stain well?

Treponema
Mycobacteria
Mycoplasma
Legionella pneumophelia
Rickettsia
Chlamydia

These Microbes May Lack Real Color

6

What "bugs" can be stained by Giemsa stain?

Chlamydia
Boriella
Rickettsia
Trypanosomes
Plasmodium

Certain Bugs Really Try my Patience

7

Which "bugs" stain with PAS?

Tropheryma whipplei

8

Which "bugs" stain with Ziehl- Neelsen (carbol fuschin) stain?

Acid- fast bacteria and protozoa

9

What "bugs" can be stained with india ink?

Cryptococcus neoformans

10

What "bugs" can be stained with silver stain?

Fung
Legionella
H. pylori

11

What components does chocolate agar have? What is it used for?

Factor V and X

H. influenzae

12

What components does Thayer- Martin agar have? What is it used for?

Vancomycin, trimethoprim, Colistin, Nystatin

Used for Neisseria species

13

What does bordet- Gengou agar contain? What is it used for?

Potatoe

B. pertussis

14

What is in Regan- Lowe medium? What is it used for?

Charcoal, blood, antibiotic

B. pertussis

15

What is Lowernstein- Jensen used for?

M. tuberculosis

16

What is eaton agar used for?

M. pneumoniae

17

What is MacConkey agar used for?

Fermentation produces acid, causing colonies to turn pink...used for lactose permenting enterics

18

Eosin- methlene blue agar used for?

E. coli--> colonies with green metallic sheen

19

What is charcoal yeast used for? What does it contain?

It contains Cystine and Fe

Legionella

20

What is Sabouraud agar used for?

Fungi

21

What is Sabouraud agar used for?

Fungi

22

What causes bugs to be anaerobic?

They lack catalase or superoxide dismutase--> so they are susuceptible to oxidative damage

23

Name the 8 facultative intracellular "bugs":

Some Nasty Bugs May Live FacultativeLY

Salmonella
Neisseria
Brucella
Mycobacterium
Listeria
Frascisella
Legionella
Yersinia pestis

24

What are the encapsulated bacteria?

Strep pneumo
Klebsiella
H. influenzae
Pseudomonas
Neisseria meningitides
Cryptococcus neoformans

E. coli, Salmonella, GBS

25

Vaccines against the capsule evoke what type of immune response?

T cell!

26

What 3 bacteira have vaccines against their capsule?

S. pneumo
HiB
Meningococcal

27

What bacteria has protein A and what does it bind? What is its function?

S. aureus

It binds the Fc region of IgG

Prevents opsonization and phagocytosis

28

What is the function of M protein Who expresses it?

Prevents phagocytosis

Expressed by Group A strep

29

What cytokines does endotoxin induce?

TNF-alpha, IL-1, IL-6

30

How are exotoxins encoded?

Plasmid or bacteriophage

31

What is the mechanism of diptheria toxin?

Inactivate elongation factor (EF-2)--> inhibit protein synthesis

32

What is the toxin of Psuedomonas? What is its mechanism?

Exotoxin A

Inactivate elongation factor (EF-2)--> inhibit protein synthesis

33

What is the toxin of shigella? What is its mechanism?

Shiga toxin

Inactivate 60S robosome by removing adenine from rRNA--> inhibit protein synthesis

34

What is the toxin of EHEC? What is its mechanism?

Shiga like toxin (verotoxin)

Inactivate 60S robosome by removing adenine from rRNA--> inhibit protein synthesis

35

What are the TWO toxins of ETEC? What are their mechanisms?

Heat labile toxin --> overactivates adenylate cyclase (increase cAMP)

Heat stabile toxin--> overactivates guanylate cyclase (increase cGMP)

36

What is the toxin of bacillus anthracis? What is ts mechanims?

Edema toxin

Mimics adenylate cyclase (increase cAMP)

37

What is the toxin of v. cholerae? What is its mechanism?

Cholera toxin

Overactivates adenylate cyclase by perminantly activating Gs--> incrased cAMP

38

What is the toxin of B. pertussis? What is its mechanism?

Pertussis toxin

Overactivates adenylate cyclase (increase cAMP) by disabling Gi--> impairing phagocytosis to permit survival of microbe

39

What is the mechanism of C. tetani and C. botulinum toxin?

Proteases that cleave SNARE and inhibit neurotransmitter release via vesicle fusion

40

What is inhibited from release in C. tetani and C. botulinum?

C. tetani--> GABA/ glycine

C. botulinum--> Ach

41

What is the toxin of C. perfringens? What is the mechanism?

Alpha toxin

Phospholipase that degrades tissue and cell membranes

42

What are the toxins of S. pyogenes? What are their mechanisms?

Streptolysin O--> protein that degrade cell membrane and lyse cells

Exotoxin A--> binds to MHC II and TCR outside of antigen binding site to cuase release of cytokines

43

What is the mechanism of S. aureus TSST-1?

Bing to MHC II and TCR outside of antigen binding site to cause overwhelming release of IL-1, IL-2, IFN- gamma and TNF- alpha

44

Which is heat stable...exotoxins or endotoxin?

Endotoxin

45

Which is heat stable...exotoxins or endotoxin?

Endotoxin

46

Which bacteria are know for undergoing transformation?

S. pneumo, HiB, Seisseria

SHiN

47

What ist he difference between F+ x F- conjugation and Hfr x F- conjucation?

Hfr can also transfer chromosomal DNA because the plasmid has gotten incorporated in the genome of the bacteria---> so the transfer may include some flanking chromosomal DNA

48

What is transposition?

Segment of DNA that can "jump" from one location to another--> can transfer genes from plasmid and chromosome (and vice versa)

49

What is the difference between generalized transduction and specialized trasduction?

Generalized--> "packaging" event

Specialzed--> "excision" event

50

Which 5 toxins are endoced for by a lysodenic phage?

ABCDE

ShigA- like toxin
Botulinum toxin
Cholera toxin
Diphtheria toxin
Erythrogenic toxin (of S. pyogenes)

51

Which bacteria is novobiocin resistant?

S. saprophyticus

52

Which bacteria is novobiocin sensitive?

S. epidermidis

53

What bacteria is optochin sensitive?

S. pneumonia

54

What bacteria is optochin resistant?

Viridans streptococci

55

What bacteria is bacitracin resitant?

GBS

56

WHat bacteria is bacitracin sensitive?

Group A strep (S. pyogenes)

57

Which bacteria are bile soluble?

S, pneumoniae

58

What bacteria grow in bile?

Enterococcus

S. bovis

59

What gram positive bacteria can grow in salt?

Enterococcus

60

Which 4 bacteria are beta hemplytic?

S. aureus
S. pyogenes
S. agalactiae
Listeria monocytogenes

61

"gram positive cocci in CLUSTERS"

S. aureus

62

What MHC does TSST bind to?

MHC II

63

How does S. epidermidis cause illness?

Biofilms!

64

What illness can S. saprophyticus cause?

UTI

65

What 3 diseases does S, pneumo typically cause?

1- Meningitis
2- Otitis media
3- Pneumonia
4- Sinusitis

66

"rusty sputum"

Strep pneumo

67

How can viridans strep cause endocarditis?

Dextrans produced by the bacteria bind to fibrin- platelet aggregates on damaged heart valves

68

"gram + in chains, beta hemolytic, bacitracin sensitive"

S. pyogenes

69

What type of hypersensitivity is rheumatic fever?

Type II

70

What type of hypersensitivity of PSGN?

Type III

71

"scarlet rash with sandpaper like texture, strawberry tpngue, circumoral pallor, subsequent desquamation"

Group A strep--> scarlet fever

72

What is the CAMP test?

GBS produces CAMP factor that enhances beta hemolysis of S. aureus

73

What is lancefield grouping based on?

Based on difference in the C carbohydrate on the bacterial cell wall

74

What bacteria can cause bacteriemia and subacute endocarditis in patients with colon cancer?

S. bovis

75

What are the 3 main symptoms of C. diphtheriae?

1- Pharyngitis with LAD
2- Myocarditis
3- Arrhythmias

76

What is the test for diphtheriae toxin?

Elek test

77

How can you get rid of spores?

Steaming at 121 C for 15 minutes

78

What is trisumus?

Lockjaw (seen in C. tetani)

79

Is C. botulinum toxin heat- stabile or heat- labile?

Heat labile

80

What are the 2 toxins of C. difficile? What are their actions?

Toxin A--> enterotoxin

Toxin B--> causes cytoskeletal disruption bia actin depolymerizatino (pseudomembranous colitis)

81

What two drugs can cause C. diff?

climdamycin
Ampicillin

82

What two drugs can cause C. diff?

climdamycin
Ampicillin

83

What makes up the capsule of B. anthracis?

D- glutamate

84

"Box car" like cells?

Anthrax

85

How is listeria contracted?

Unpasteurzed diary products and cold deli meats

Transplacental transmission

Vaginal transmission at birth

86

What is the motility of Listeria?

Tumbling--> intracellular movement

87

What are the symptomsof listeria in infants?

Early spread--> sepsis

Late spread--> meningitis

88

Which is an anaerobe...actinomyces or nocardia?

Actinomyces

89

"sulfer granules"

Actinomyces

90

How is actinomyces treated?

Penicillin

91

How is nocardia treated?

Sulfonamides

92

"fibrocaseous cavitary lesion in upper lobe of lung"

Secondary tuberculosis

93

"Ghon focus in lower/ mid zones of lung and hilar lymph node LAD"

Primary TB (Ghon complex)

94

What temperature does leprosy like to grow in?

Cool temperatures

95

What cells does leprosy infection?

Infects skin and superficial nerves

96

Which leprosy is a Th2 mediated response?

Lepromatous leprosy--> low cell mediated

97

Which leprosy is a Th1 mediated response?

Tuberculoid leprosy--> high cell mediated response

GRANULOMAS

98

Which neisseria can ferment maltose?

N. meningitidis

99

What are the gram negative Coccoid Rods?

H. flu
Pasturella
Brucella
Bordetella

100

Name 5 lactose fermenters?

Klebsiella
E. coli
Enterobactier
Citrobacter
Serratia

101

Which bacteria produce H2S?

Salmonella
Proteus
Yersinia

102

Which bacteria is oxidase negative and H2S negative?

Shigella

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