Antimicrobial Agents Flashcards Preview

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Flashcards in Antimicrobial Agents Deck (41)
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1
Q

Beta-Lactam Drugs

A

MOA • inhibition of enzymes (transpeptidase) needed for peptidoglycan formation • formation of covalent complexes with enzymes

2
Q

Penicllins

A

MOA • binds to enzyme penicillin binding protein (transpeptidase) • to mediate transpeptidation reaction

3
Q

Cephalosporins

A

•can withstand the action of beta-lactamases •more modifiable •structurally similar to penicillin

4
Q

Glycopeptides

A

MOA • binds to terminal D-Ala-D-Ala of the pentapeptide-glycosyl peptidoglycan intermediates • binds to substrate (D-Ala, D-Ala)

5
Q

Glycopeptides

A

• interferes with cross-linking in peptidoglycan

6
Q

Cycloserine

A

MOA • inhibits synthesis of peptidoglycan precursors (D-Ala D-Ala) in the cytoplasm

7
Q

Bacitracin

A

MOA • inhibits transport of lipid-bound precursors across the cytoplasmic membrane

8
Q

Bacitracin

A

MOA • inhibits NAG and NAM synthesis

9
Q

Polymyxins

A

MOA • acts like detergents which interact with phospholipids

10
Q

Polymyxins

A

MOA • increases permeability and macromolecule leakage

11
Q

Folate

A

important DNA synthesis precursor

12
Q

Sulfonamides

A

MOA • competitive inhibition of folic acid synthesis • binds to dihydropteroate synthase

13
Q

Trimethoprim

A

MOA • blocks steps of tetrahydrofolase formation by dihydrofolate reductase prevention

14
Q

Trimethoprim

A

MOA • targets the folic acid pathway

15
Q

Fluoroquinolones

A

MOA • binds and interferes with DNA gyrase (for Gr -) and topoisomerase IV (for Gr +)

16
Q

Metronidazole

A

MOA • Nitro group is reduced by nitroreductase • responsible for DNA breakage due to chemical action

17
Q

Rifamycin

A

MOA • binds to DNA dependent RNA polymerase

18
Q

Chloramphenicol

A

MOA • inhibits translation through elongation step inhibition

19
Q

Macrolides

A

MOA • inhibits tRNA (transfer RNA) • inhibits translation by elongation inhibition through 23S RNA binding

20
Q

Oxazolidinones

A

MOA • inhibits initiation of mRNA translocation • inhibits protein synthesis by interacting with 23S RNA

21
Q

Tetracyclines and Doxycycline

A

MOA • inhibits protein synthesis by binding reversibly to the 30S ribosomal subunit

22
Q

Tetracycline and Doxycycline

A

targets intracellular pathogens

23
Q

Aminoglycosides

A

used with penicillins in order to diffuse and enter bacterial cell

24
Q

1st Line Drugs

A

Isoniazid Less side effects Pyrazinamide Rifampicin

25
Q

2nd Line Drugs

A

Streptomycin Ethambutol TB treatment (1st line resistant)

26
Q

Inhibition of Cell Wall Synthesis

A

Beta-Lactams Cycloserine Bacitracin

27
Q

Inhibition of Cell Membrane Function

A

Polymyxins

28
Q

Inhibitors of Folate Synthesis

A

Sulfonamides Trimethoprim

29
Q

Interference with DNA synthesis

A

Fluroquinolones Metronidazole

30
Q

Interference with RNA synthesis

A

Rifamycins

31
Q

Inhibition of Protein Synthesis 30S ribosome inhibition

A

Chloramphenicol Macrolides Oxazolidinones

32
Q

Inhibition of Protein Synthesis 30S ribosome inhibition

A

Tetracyclines Doxycyclines Aminoglycoside

33
Q

Streptomycin

Gentamycin

Tobramycin

Amikacin

Neomycin

A

Give aminoglycosides examples.

(Hint: There are five.)

34
Q

Biological resistance

A

changes that results in observably reduced susceptibility of organism to a particular antimicrobial agent

35
Q

Clinical resistance

A

antimicrobial susceptibility has been lost

36
Q

Intrinsic/inherent

A

resistance is predictable

37
Q

Acquired

A

resistance is unpredictable

38
Q

mefA

A

Give the gene.

Streptococcus pneumoniae

39
Q

msrA

A

Staphylococcus aureus & Enterococcus

40
Q

mreA

A

Streptococcus agalactiae

41
Q

Lateral Gene Transfer

A

most important strategy of bacteria to spread resistance