Antibiotics Flashcards
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 _
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
Three general mechanisms by which antibiotics kill bacteria
- Inhibit bacterial cell wall
- Inhibit DNA/RNA synthesis
- Inhibit protein synthesis
Which antibiotics are cell wall inhibitors?
“My VIP car of cell wall”
Monobactams
Vancomycin
Isoniazid
Penicillins
Carbapenems
Cephalosporins
Wall
Most of the cell wall inhibiting antibiotics contain _ which will disrupt bacterial cell wall formation
Most of the cell wall inhibiting antibiotics contain Beta-lactam rings which will disrupt bacterial cell wall formation
* The exception is vancomycin
How does vancomycin inhibit the cell wall?
Vancomycin binds to D-alanyl-D-alanine in bacterial cell walls
_ (penicillin derivative) improved drug uptake
Aminopenicillins (penicillin derivative) improved drug uptake
_ (penicillin derivative) are resistant to Beta-lactamase
Beta-lactamase (penicillin derivative) are resistant to Beta-lactamase
_ (penicillin derivative) have a wider spectrum
Ureidopenicillins (penicillin derivative) have a wider spectrum
Sulfonamides and trimethoprim inhibit _ formation
Sulfonamides and trimethoprim inhibit tetrahydrofolate formation –> inhibits DNA and RNA production
Quinolones and fluoroquinolones stop DNA/RNA synthesis by binding to _
Quinolones and fluoroquinolones stop DNA/RNA synthesis by binding to transcription enzymes to destroy the DNA during transcription or replication
_ is a DNA destroyer that enters the cell via passive diffusion and then forms toxic free-radicals to disrupt DNA integrity
Metronidazole is a DNA destroyer that enters the cell via passive diffusion and then forms toxic free-radicals to disrupt DNA integrity
Glycylcyclines, aminoglycosides, tetracyclines, and amphenicols are all _ (type antibiotics)
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
Linezolid disrupts protein production by inhibiting formation of the complex that is needed to _
Linezolid disrupts protein production by inhibiting formation of the complex that is needed to translate mRNA into protein
Cell wall inhibitors
DNA/RNA synthesis inhibitors
Protein synthesis inhibitors
Oxazolidinone – Linezolid – MRSA, vancomycin-resistant enterococci (VRE)
In order to determine antibiotic susceptibility, we use a measurement called _
In order to determine antibiotic susceptibility, we use a measurement called minimum inhibitory concentration
The MIC determines the minimal antibiotic concentration required to _
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)
The _ is the minimum concentration of antibacterial that would result in bacterial cell death
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
As the MIC approached the MBC, the antibiotic is considered more (bactericidal/bacteriostatic)
As the MIC approached the MBC, the antibiotic is considered more bactericidal
* Meaning they actually kill bacteria as their primary action
_ treatment describes antibacterial treatment that may be initiated before knowing the causative agent
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
