Test 3: 36: antibiotics part 1 Flashcards
These drugs kill bacteria. Most common mechanism is by loss of cell wall integrity - osmotic pressure bursts the bacteria.
bactericidal drugs
penicillin, cephalosporin, aminoglycosides
what are some bactericidal drugs
Penicillins, Cephalosporins, Aminoglycosides
what are some bacteriostatic drugs
Erythromycin, Tetracyclin, Chloramphenicol
what is a bacteriostatic drug
Inhibit bacterial growth. Typically these drugs target metabolic processes or Nucleic acid synthesis reactions. Do not kill bacteria. Bacteria need to be cleared by the host immune system.
Erythromycin, Tetracyclin, Chloramphenicol
should you use bactericidial with bacteriostatic drugs
no
most bactericidal drugs require bacterial growth
— are compounds made by one organism to inhibit or kill another.
Natural Antibiotics
Therapeutic — can be Natural, Semi-Synthetic or fully Synthetic.
antibiotics
— Antibiotics inhibit bacterial growth
Bacteriostatic
need intact immune system to clear stalled bacteria
— Antibiotics kill bacteria.
Bactericidal
what are 4 differences that bacteria have that are targets for antibiotics
Cell Wall Synthesis: Bacteria have peptidoglycan
Nucleic Acid Synthesis: Specific DNA-gyrase in bacteria
Protein Synthesis: Differences in Ribosome structure (70S v 80S)
Folic Acid Synthesis: Mammals don’t make it
what are some cell wall synthesis antimicrobials
A. The β-lactams (Penicillins and Cephalosporins)
B. Polypeptides (Vancomycin, Bacitracin)
C. Cycloserine
what are some folic acid metabolism antibiotics
Sulfanilamide, Trimethoprim
what are some DNA/RNA synthesis antibiotics
Rifamycins, Fluoroquinolones Novobiocin, Metronidazole
what are some antibiotics that target cell membrane function
Polymyxin B
what are some antibiotics that target protein synthesis
Aminoglycosides, Tetracyclines, Puromycin, Macrolides, Lincosamides, Chloramphenicol
Most cell wall synthesis inhibitors are —
Bactericidal
A. The β-lactams (Penicillins and Cephalosporins)
B. Polypeptides (Vancomycin, Bacitracin)
C. Cycloserine
Most protein synthesis inhibitors are —
Bacteriostatic
Aminoglycosides, Tetracyclines, Puromycin, Macrolides, Lincosamides, Chloramphenicol
what are some βlactam antibiotics
Penicillins and Cephalosporins
inhibit cell wall synthesis
what do gram positive bacteria wall look like
Staphylococcus, Streptococcus, Bacillus, Listeria, Nocardia, Clostridium, Enterococcus, Corynebacterium.
what does gram negative bacteria look like
Escherichia, Klebsiella, Salmonella, Neisseria, Bordatella, Brucella, legionella, Pasteurella, Bacteroides, Shigella, Yersinia.
where does penicillin bind to bacteria
at PBP (penicillin binding proteins) located in the cytoplasmic membrane of the cell wall of bacteria
penicillin (β lactam) attacks cell wall synthesis
why do gram negative bacteria not stain?
stain binds to cell wall
gram negative bacteria have outermembrane with LPS that prevents stain from getting to cell wall
Antibiotics that target cell wall synthesis Specifically inhibit / interfere with the — synthesis pathway
peptidoglycan
A. The β-lactams (Penicillins and Cephalosporins)
B. Polypeptides (Vancomycin, Bacitracin)
C. Cycloserine
which generation of cephalosporin is better for Gram negative bacteria
1st gen: Gram positive > Gram negative
2nd gen:
3rd gen: gram += gram negative
