Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > Y Lecture 1: Anti-Microbial Agents 1 > Flashcards

Y Lecture 1: Anti-Microbial Agents 1 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is the broad mechanism of action of beta lactams?

A

Inhibition of cell wall synthesis

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

What is the broad mechanism of action of glycopeptide antibiotics?

A

Inhibition of cell wall synthesis

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

What 3 groups of antibiotics are classified as beta lactams?

A

Penicillins
Cephalosporins
Carbapenems

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

Name 2 glycopeptide antibiotics

A

Vancomycin
Teicoplanin

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

Describe the mechanism of action of beta lactams

A

Inhibits transpeptidase, which is an enzyme that forms cross links during the formation of the cell wall. The resulting cell wall is therefore weak, and so the bacteria lyse because of osmotic pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How does the cell wall of gram pos and gram neg bacteria differ?

A

Gram pos has peptidoglycan

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

What bacteria is penicillin active against?

A

Gram pos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What bacteria is amoxicillin active against?

A

Broad spectrum: gram pos and many gram neg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Is streptococci gram pos or neg?

A

Gram pos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which beta lactam antibiotic is effective against pseudomonas?

A

Piperacillin

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

How can beta lactam resistance be overcome?

A

Include a beta lactamase inhibitor
Eg. Clavulanic acid + amoxicllin (in co-amoxiclav)

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

Is pseudomonas gram pos or gram neg?

A

Gram neg

(Pseudo”moan”as - ‘moan’ = negative)

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

Is neisseria meningitis gram pos or gram neg?

A

Gram neg

(Neisseria starts with N = negative)

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

Recall an antibiotic that is associated with C. difficile

A

Ceftriaxone (cephalosporin)

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

Which beta lactam antibiotics are stable to ESBL organisms?

A

Carbapenems

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

Recall a caution of beta lactam antibiotic

A

Excreted renally so reduce dose if renal impairment

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

What type of bacteria are glycopeptides effective against?

A

Gram pos only - they are large molecules so can’t penetrate gram neg cell wall

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

What are glycopeptides particularly useful for?

A

MRSA infection

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

What is a caution of glycopeptide antibiotics?

A

They are nephrotoxic

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

Recall the broad mechanism of action of glycopeptide antibiotics

A

Prevent peptide cross links in cell wall

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

Recall the broad mechanism of action of aminoglycosides

A

Bind to 30s ribosomal subunit, preventing elongation of polypeptide chain

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

Recall 2 examples of aminoglycoside antibiotics

A

gentamicin

amikacin

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

What type of bacteria are aminoglycoside antibiotics effective against?

A

Gram neg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Recall 2 toxicities of aminoglycosides

A

Ototoxicity
Nephrotoxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What type of bacteria are macrolides effective against?

A

Gram pos

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are macrolides particularly useful for?

A

Mild staph or strep infections in patients who are allergic to penicillin

27
Q

Recall 2 macrolide antibiotics

A

Azithromycin
Clarithromycin

28
Q

Recall the broad mechanism of action of macrolides

A

Bind to the 50s subunit of ribosomes

29
Q

Recall a class of antibiotic you should never give to children or pregnant women

A

Tetracyclines

30
Q

Recall one side effect of tetracycline antibiotics

A

Light-sensitive rash

31
Q

What type of bacteria are tetracylines effective against?

A

They are broad spectrum

32
Q

Recall the broad mechanism of action of tetracyclines

A

Bind to 30s subunit of ribosomes

33
Q

What type of bacteria is chloramphenicol effective against?

A

Many - it is v broad spectrum

34
Q

Why is chloramphenicol rarely used?

A

Risk of aplastic anaemia and grey baby syndrome in neonates due to inability to metabolise drug

35
Q

Recall 2 specific bacteria that macrolides are effective against

A

Campylobacter sp

Legionella pneumophila (macrolides = erythromycin/ azithromycin/ clarithromycin)

36
Q

Recall the broad mechanism of action of chloramphenicol

A

Binds to 50s subunit of ribosomes - inhibits formation of peptide bonds during translation

37
Q

Recall the broad mechanism of action of oxazolidinones

A

Binds to the 23s and 50s subunit of ribosomes to prevent 70s subunit formation

38
Q

Recall two types of bacteria that oxazolidinones are particularly active against

A

MRSA and VRE

39
Q

Recall an example of oxazolidinones

A

Linezolid

40
Q

Recall one potential side effect of oxazolidinones

A

Thrombocytopaenia

41
Q

Recall the broad mechanism of action of fluoroquinolones

A

Act on alpha subunit of DNA gyrase

42
Q

Recall 4 uses of fluoroquinolones

A
  • UTI
  • Pneumonia
  • Atypical pneumonia
  • Bacterial gastroenteritis
43
Q

Recall 2 examples of fluoroquinolone antibiotics

A
  • Levofloxacin
  • Moxifloxacin
44
Q

Give an example of a nitromidazole antibiotic

A

Metronidazole

45
Q

Recall types of organisms that metronidazole is effective against

A

Anaerobes

Protozoa

46
Q

When should metronidazole be taken?

A

Right after visiting the toilet as it sits in bladder

47
Q

Recall the broad mechanism of action of rifampicin

A

Binds to DNA-dependent RNA polymerase to inhibit RNA synthesis

48
Q

Recall the main use of rifampicin

A

TB treatment

49
Q

Recall one side effect of rifampicin

A

Turns secretions orange

50
Q

Recall one condition of rifampicin prescription

A

Should never be prescribed alone as resistance develops very quickly

51
Q

Colistin is very toxic. Why is it coming back into use?

A

It is active agianst certain multi-drug resistant bacteria

52
Q

What is daptomycin licensed for the treatment of?

A

MRSAVRE

53
Q

Recall the 2 classes of antibiotic that inhibit folate synthesis

A

Sulphonamides

Diaminopyrimidines

54
Q

Give an example of a sulphonamide

A

Trimethoprim

55
Q

What is the main use of trimethoprim

A

Uncomplicated UTI

56
Q

What are the 4 main mechanisms of resistance

A
  1. Inactivation (eg beta latamases)
  2. Altered target (so antibiotic no longer binds - important in MRSA where bacteria change the penicillin-binding protein, and in protein-synthesis inhibitors where the binding of the ribosome subunit is prevented)
  3. Reduced accumulation(most important in gram negs - either due to efflux or to reduced uptake)
  4. Bypass(particularly important for folate inhibitors - bacteria can change the enzyme they use)
57
Q

Which antibiotic is best for treating pseudomonas jirovecii?

A

Co-trimoxazole

58
Q

What is the broad mechanism of action of nirtromidazoles?

A

Inhibit DNA synthesis

59
Q

Which bacteria typically forms “gram pos cocci in clusters”?

A

Staphylococcus

60
Q

Which bacteria typically forms “gram pos cocci in chains”?

A

StreptococcusStrep sounds like ‘stripe’ = chain

61
Q

What gram stain status are enterococci?

A

Positive(“Enter-o-coccus” = like letting someone in, positive thing to do)

62
Q

Is haemophilus gram pos or neg?

A

Gram negHa”emo”philus - emo = negative

63
Q

Is listeria gram pos or neg?

A

PositiveLister = good man = positive

Microbiology (11 decks)

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