X_Exam1 Mfm2_17

Front 1

antibiotics that prevent the synthesis of intact peptidoglycan are called:

Back 1

bactericidal

Front 2

Vancomycin prevents insertion of the ... into the .... by binding to ...

Back 2

peptidoglycan chain
cell wall
D-ala-D-ala

Front 3

Bacitracin is a peptide antibiotic that interferes with the formation of ...

Back 3

bactoprenol phosphate

Front 4

Cycloserine has a structure that is very similar to ... and it inhibits ...

Back 4

D-ala
the enzymes that make D-ala-D-ala

Front 5

Fosfomycin prevents the synthesis of ...

Back 5

UDP-N-acetylmuramic acid

Front 6

... and ... both inhibit mycolic acid synthesis and are bactericidal against ...

Back 6

Isoniazid
ethionamide
mycobacteria

Front 7

what are the antibiotics that inhibit protein synthesis:
1.
2.
3.
4.
5.
6.
7.

Back 7

1. Aminoglycosides
2. Tetracyclines
3. Oxazolidinones
4. Chloramphenicol
5. Macrolides
6. Lincosamides
7. Streptogramins

Front 8

... is active against 70s and 80s ribosomes and requires ... to get into cell. Eukaryotic cells do not accumulate this antibiotic and therefore are not killed by it. these antibiotics are ... (mechanism of action)

Back 8

tetracycline
active transport mechanism
bacteriostatic

Front 9

Streptogramin antibiotics are a mixture of ..., called group A ... and group B ... the two peptides act synergistically to prevent protein synthesis by ...

Back 9

two different cyclic peptides
streptogramins
streptogramins
preventing peptide bond formation

Front 10

what are the antibiotics that inhibit DNA structure:
1.
2.

Back 10

1. Quinolones, and the newer versions, fluoroquinolones
2. Metronidazole

Front 11

what is the mode of action for the antibiotics quinolones and fluoroquinolones act:

Back 11

inhibit the enzymes which supercoil the DNA

Front 12

what is the mode of action for the antibiotic metronidazole:

Back 12

bacteria reduce a nitro group on metronidazole that make the antibiotic highly toxic that disrupts DNA

Front 13

... forms a stable complex with RNA polymerase and prevents chain initiation.

Back 13

Rifampin (aka rifampicin)

Front 14

there is a group of cyclic polypeptides called ..., which interfere with the ... portion of the outer membrane, causing cell death. these antibiotics are usually administered ... and are effective against ... bacteria.

Back 14

polymyxins
Lipid A
topically
Gram-negative

Front 15

what antibiotics inhibit bacterial metabolism and how:
1.
2.

Back 15

1. Sulfonamides prevent folic acid synthesis
2. Trimethoprim inhibits the enzyme, dihydrofolate reductase, which is required to convert folic acid to the active form, tetrahydrofolate

Front 16

... and ... act synergistically, and are usually prescribed together

Back 16

Sulfonamides
trimethoprim

Front 17

tetrahydrofolate is required for thymidine biosynthesis therefore the antibiotic ... prevents DNA synthesis

Back 17

trimethoprim

Front 18

what are the major mechanisms for resistance:
1.
2.
3.

Back 18

1. destruction of antibiotic
2. preventing antibiotic from reaching critical concentration within bacterial cell
3. alteration of target site

Front 19

what is an example of destruction of antibiotic:

Back 19

breaking down of β-lactam ring

Front 20

The β-lactamases have different activity spectra. Some are active only against ... and some are active against all the different classes of ...

Back 20

penicillins (penicillinases)
β-lactamases

Front 21

Aminoglycosides can be destroyed by enzymes that add ... or ... or even add an entire ... molecule to the antibiotic. Once these groups are added to the antibiotic, it is no longer able to bind to the ... ribosomal subunit and prevent protein synthesis

Back 21

phosphate
acetyl groups
AMP
30s

Front 22

how can bacteria cells prevent antibiotic from reaching a critical concentration within the bacterial cell:
1.
2.

Back 22

1. alter porins size
2. pump the antibiotic out of the cell

Front 23

One mechanism by which bacteria can become resistant to β-lactam antibiotics is by altering the ... so that the antibiotic can no longer bind to them.

what organism uses that mechanism:

Back 23

penecillin bind proteins
Staphylococcus aureus uses for methicillin resistance

Front 24

Some bacteria can alter their ... so that vancomycin no longer prevents cross-linking

Back 24

peptidoglycan

Front 25

By altering the ... ribosomal subunit, bacteria can become resistant to both streptogramins and macrolides

Back 25

50s

Front 26

the antibiotics streptogramins and macrolides target the ... in bacteria

Back 26

50s ribosomal subunit

Front 27

Resistance to β-lactam antibiotics is mediated by two different mechanisms:
1.
2.

Back 27

1. β-lactamase
2. production of a second PBP

Front 28

what 2 genes make MRSA strains resistance to all β-lactam antibiotics:
1.
2.

Back 28

1. mecA
2. blaZ

Front 29

clustering virulence genes in ... helps in spreading virulence from strain to strain.

Back 29

pathogenicity islands

Front 30

Some MRSA strains have become resistant to vancomycin. The gene which provides vancomycin resistance is called ... and is carried on a transposon (Tn1546). The transposon is transferred from one strain to another via ...

It is likely that this transposon was transferred to Staphylococcus aureus from ...

Back 30

vanA
plasmid
Enterococcus faecalis

Front 31

Aminoglycoside resistance is due to ... of the antibiotics

Back 31

inactivation

Front 32

Staphylococcus aureus makes ... which removes tetracyclines from the cell.

Back 32

an efflux pump

Front 33

Chloramphenicol resistance is due to ... of the antibiotic by the product of the ... gene

Back 33

acetylation
cat

Front 34

Resistance to macrolides and lincosamides is due to ... of the ... found in the 50s ribosomal subunit

Back 34

methylation
23s rRNA

Front 35

Resistant to the streptogramins is due to ... of the streptogramin A component and ... of the streptogramin B component

Back 35

efflux
inactivation

Front 36

what are the two mechanisms that have evolved in Staphylococcus aureus to provide resistance to the fluoroquinolones:
1.
2.

Back 36

1. efflux pump
2. change in topoisomerase

Front 37

Resistance to rifampicin is due to chromosomal mutations in the ...

Back 37

β-subunit of RNA polymerase

Front 38

Resistance to trimethoprim is due to production of a second ... which is not inhibited by trimethoprim

Back 38

dihydrofolate reductase

Front 39

Resistance to sulfonamides is due to a chromosomal mutation which increases production of ... which overcomes the competitive inhibition of the enzyme in ...

Back 39

p-aminobenzoic acid
folic acid synthesis