Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Micro > Basic Bacteriology and Toxins > Flashcards

Basic Bacteriology and Toxins Flashcards

1
Q

Obligate anaerobes

A 
Use an O2-dependent system to generate ATP
Nagging Pests Must Breathe:
Nocardia
Pseudomonas aeruginosa
MycoBacterium TB
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Obligate anaerobes

A

Can’t grow or make ATP when in O2

Lack catalase and/or superoxide dismutase = susceptible to oxidative damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Examples of obligate anaerobes

A

Anaerobes Can’t Breathe Air
Clostridium
Bacteroides
Actinomyces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Obligate intracellular bugs

A

Rickettsia

Chlamydia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Facultative intracellular

A 
"Some Nasty Bugs May Live FacultativeLY"
Salmonella
Neisseria
Brucella
Mycobacterium
Listeria
Francisella
Legionella
Yersinia pestis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the Quellung Rxn

A

Anticapsular serum added to bacteria –> capsule swells under microscope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Encapsulated bacteria

A 
Even Some Pretty Nasty Killers Have Shiny Bodies
E Coli
Strep pneumo
Pseudomonas
Neisseria
Klebsiella
H Flu B
Salmonella Typhi
Group B strep
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the catalase + organisms

A 
PLACESS
Pseudomonas
Listeria
Aspergillus
Candida
E coli
S aureus
Serratia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the urease-positive bugs

A 
CHuck Norris hates PUNKSS
Cryptococcus
H. pylori
Proteus
Ureaplasma
Nocardia
Klebsiella
S. epidermidis
S. saprophyticus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Pigment producing bacteria

A

Actinomyces israelii - yellow granules
S aureus - yellow/gold pigment
Pseudomonas aeruginosa - blue/green
Serratia marcescens - red

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Virulence factor Protein A

A

Binds Fc region of IgG which prevents opsonization and phagocytosis
S. aureus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Virulence factor IgA protease

A

Enzyme that cleaves IgA

Helps colonize respiratory mucosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which bugs secrete IgA protease

A

S. pneumo
H. flu
Neisseria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Virulence factor M protein

A

Helps prevent phagocytosis

Group A strep express

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is unique about mycoplasma

A

No cell wall

Contain sterols

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is unique about mycobacteria

A

Have cell walls - they contain mycolic acid
High lipid content
Resistant to gram staining
Resilient in many environments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is endotoxin found

A

Within outer membrane of gram negative bacteria
It’s the lipopolysaccharide component.
Lipid A - trapped in outer cell membrane until cell lysed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does endotoxin activate

A

Macrophages: IL-1, TNFa, NO (fever, hypotension)
Complement: C3a (hypotension, edema), C5a (neutrophil chemotaxis)
TF: Coagulation cascade –> DIC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What bacteria usually produce exotoxins

A

Gram + with plasmids or bacteriophages that code for them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Are exotoxins antigenic?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are superantigens

A

Exotoxins that can bind MHC class II receptor and TCR –> Polyclonal expansion of T cell –> massive immune response, cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are two superantigen producers

A

Staph aureus

Strep pyogenes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What known toxins are secreted by Staph Aureus and waht are their actions

A 
4 hemolysins
alpha - hemolysis
beta - sphingomyelinase
gamma toxin - hemolysin, leukocidin
delta toxin - toxic to erythrocytes and other cells - hemolysis
Leukocidin - destroys leukocytes
24
Q

What is leukocidin

A

Toxin produced by Staph Aureus - affect neutrophils and macrophages

25
Q

What are the two super antigens produced by Staph A?

A

Enterotoxins A-E

TSST - toxic shock syndrome

26
Q

What toxins are secreted by strep pyogenes? (GAS)

A
  • Streptolysin O
  • Streptolysin S
  • Erythrogenic/pyrogenic toxins (scarlet fever)
27
Q

Streptolysin O

A

Secreted by strep pyogenes
Causes hemolysis (is oxygen labile)
Antibodies to this to detect recent infection ASO titers)

28
Q

Streptolysin S

A 
Secreted by strep pyogenes
Causes hemolysis (is oxygen stable)
29
Q

Diphtheria toxin MOA

A

Produced by Corynebacterium

Inactivates EF-2 - inhibits protein synthesis

30
Q

Diphtheria toxin symptoms

A

Pharyngitis with gray pseudomembranes

Cardiac and nerve cell damage

31
Q

Pseudomonas aeruoginosa exotoxin

A

Exotoxin A

32
Q

Mechanism of action of pseudomonas Exotoxin A

A

Inactivates EF-2 –> inhibits protein synthesis –> host cell death

33
Q

Shigella toxin

A

Shiga toxin

34
Q

Shiga toxin MOA

A

Cleaves host rRNA at adenine base in 60s ribosome subunit –> inhibits protein synthesis

35
Q

Enterohemorrhagic E Coli (EHEC)

A

0157:H7
Forms shiga-like toxin
Causes bloody diarrhea
Damage to renal and endothelial cells –> HUS

36
Q

What causes HUS

A

EHEC

37
Q

Triad of HUS

A

Hemolytic anemia
Thrombocytopenia
Acute renal failure

38
Q

Enterotoxigenic E Coli (ETEC) toxins

A

Heat labile toxin

Heat stable toxin

39
Q

What does ETEC heat labile toxin do

A

Overactivates cAMP –> Increased secretion of Cl- in gut and water efflux

40
Q

What does ETEC heat stable toxin do

A

Overactivates cGMP –> decreased reabsorbtion of NaCl and water in gut

41
Q

What is the leading cause of traveler’s diarrhea

A

ETEC

42
Q

Yersinia entercolitica toxin

A

Similar to heat stable toxin from ETEC - stimulates cGMP

“pseudoappendicitis”

43
Q

Bacillus anthracis

A

Anthrax toxin

44
Q

What are the 3 components of anthrax toxin

A

Edema factor = Adenylyl cyclase
Lethal factor
Protective Ag

45
Q

Cholera toxin

A

Stimulates AC –> increase cAMP –> permanently activating Gs. Rice water stools

46
Q

Bordetella pertussis toxin

A

Increases cAMP by binding to and inactivating Gi proteins -> increases cAMP

47
Q

Clostridium tetani toxin

A

Tetanospasmin

48
Q

MOA of Tetanospasmin

A

Blocks release of GABA and glycine (inhibitory NTs) –> lock jaw, spasm

49
Q

Clostridium botulinum toxin MOA

A

Work at NMJ to inhibit release of Ach -> flaccid paralysis

50
Q

Clostridium perfringens toxin

A

Alpha toxin: A phospholipase that causes gas gangrene and myonecrosis
Enterotoxin: Food poisoning

51
Q

What toxin inhibits the inhibitor of adenylate cyclase

A

Pertussis toxin

52
Q

What toxin(s) stimulate adenylate cyclase causing Cl- and water into the gut, rice water diarrhea

A

Cholera toxin

Heat labile ETEC toxin

53
Q

What toxins destroy leukocytes

A

Staph aureus:
gamma hemolysin
Leukocidin

54
Q

What toxin is composed of edema factor, lethal factor, and protective antigen

A

Anthrax toxin

55
Q

What toxin causes scarlet fever

A

Pyrogenic toxins of strep pyogenes

56
Q

What toxin(s) inactivate EF-2

A

Diptheria toxin and Exotoxin A (pseudomonas)

Micro (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions