Antibiotics

Question 1

We use ‘antibiotics’ to include medications that target fungi, archaea, parasites, and bacteria; if we are only talking about medications that treat bacteria specifically, a better term is _

Answer 1

We use ‘antibiotics’ to include medications that target fungi, archaea, parasites, and bacteria; if we are only talking about medications that treat bacteria specifically, a better term is antimicrobials

Question 2

Three general mechanisms by which antibiotics kill bacteria

Answer 2

1. Inhibit bacterial cell wall
2. Inhibit DNA/RNA synthesis
3. Inhibit protein synthesis

Question 3

Which antibiotics are cell wall inhibitors?

Answer 3

“My VIP car of cell wall”
Monobactams
Vancomycin
Isoniazid
Penicillins
Carbapenems
Cephalosporins
Wall

Question 4

Most of the cell wall inhibiting antibiotics contain _ which will disrupt bacterial cell wall formation

Answer 4

Most of the cell wall inhibiting antibiotics contain Beta-lactam rings which will disrupt bacterial cell wall formation
* The exception is vancomycin

Question 5

How does vancomycin inhibit the cell wall?

Answer 5

Vancomycin binds to D-alanyl-D-alanine in bacterial cell walls

Question 6

_ (penicillin derivative) improved drug uptake

Answer 6

Aminopenicillins (penicillin derivative) improved drug uptake

Question 7

_ (penicillin derivative) are resistant to Beta-lactamase

Answer 7

Beta-lactamase (penicillin derivative) are resistant to Beta-lactamase

Question 8

_ (penicillin derivative) have a wider spectrum

Answer 8

Ureidopenicillins (penicillin derivative) have a wider spectrum

Question 9

Sulfonamides and trimethoprim inhibit _ formation

Answer 9

Sulfonamides and trimethoprim inhibit tetrahydrofolate formation –> inhibits DNA and RNA production

Question 10

Quinolones and fluoroquinolones stop DNA/RNA synthesis by binding to _

Answer 10

Quinolones and fluoroquinolones stop DNA/RNA synthesis by binding to transcription enzymes to destroy the DNA during transcription or replication

Question 11

_ is a DNA destroyer that enters the cell via passive diffusion and then forms toxic free-radicals to disrupt DNA integrity

Answer 11

Metronidazole is a DNA destroyer that enters the cell via passive diffusion and then forms toxic free-radicals to disrupt DNA integrity

Question 12

Glycylcyclines, aminoglycosides, tetracyclines, and amphenicols are all _ (type antibiotics)

Answer 12

Glycylcyclines, aminoglycosides, tetracyclines, and amphenicols are all protein synthesis inhibitors
* These four bind to ribosomal subunits
* Think GATA = cat in spanish
* Macrolides also do this

Question 13

Linezolid disrupts protein production by inhibiting formation of the complex that is needed to _

Answer 13

Linezolid disrupts protein production by inhibiting formation of the complex that is needed to translate mRNA into protein

Question 14

Cell wall inhibitors

Answer 14

Question 15

DNA/RNA synthesis inhibitors

Answer 15

Question 16

Protein synthesis inhibitors

Answer 16

Oxazolidinone – Linezolid – MRSA, vancomycin-resistant enterococci (VRE)

Question 17

In order to determine antibiotic susceptibility, we use a measurement called _

Answer 17

In order to determine antibiotic susceptibility, we use a measurement called minimum inhibitory concentration

Question 18

The MIC determines the minimal antibiotic concentration required to _

Answer 18

The MIC determines the minimal antibiotic concentration required to inhibit the growth of the bacterium
* We can grow S aureus in increasing concentrations of methicillin-filled broth to see if it is MRSA (high MIC suggests MRSA)

Question 19

The _ is the minimum concentration of antibacterial that would result in bacterial cell death

Answer 19

The minimum bactericidal concentration (MBC) is the minimum concentration of antibacterial that would result in bacterial cell death
* Not commonly used
* Helpful to know if an antibacterial is more bactericidal than bacteriostatic

Question 20

As the MIC approached the MBC, the antibiotic is considered more (bactericidal/bacteriostatic)

Answer 20

As the MIC approached the MBC, the antibiotic is considered more bactericidal
* Meaning they actually kill bacteria as their primary action

Question 21

_ treatment describes antibacterial treatment that may be initiated before knowing the causative agent

Answer 21

Empiric treatment describes antibacterial treatment that may be initiated before knowing the causative agent
* We use local surveillance data to understand the bacterial resistance rates and infection rates in an area