Tutorials: 1 & 4 ✅ Flashcards
Mode of action of Antibiotics
Interfere with the biochemical pathways of microbes
What are the categories of antibiotics based on?
Their mode of action
What may excessive use or misuse of antibacterial substances result in?
The creation of resistant bacterial strains
Antibiogram
The result of lab testing for the sensitivity of an isolated bacterial strain to different antibiotics
Categories of antibiotics
Aka the 5 modes of action
- Inhibition of the bacterial cell wall (peptidoglycan) synthesis
- Destruction of the cell membrane
- Inhibition of protein synthesis by binding to prokaryotic ribosomes
- Inhibition of nucleic acid synthesis
- Growth supplement analogues
Inhibition of the bacterial cell wall (peptidoglycan) synthesis
For gram + bacteria ONLY
Eg penicillin, ampicillin, methicillin, cephalosporins
Destruction of the cell membrane
Mode of action of antibiotics
Polymyxins: for gram (-) bacteria
-eg polymyxins B and E
Polyenes: for fungi
-eg amphotericin B, nystatin
Inhibition of protein synthesis by b in ding to prokaryotic ribosomes
Used ONLY for bacteria
-eg streptomycin, chloramphenicol, tetracycline, erythromycin
Inhibition of nucleic acid synthesis
-eg rifampicin: used for myobacteria
-metronidazole (for anaerobes)
Growth supplement analogues
Mode of action
-sulfonamides (folic acid antagonists)
-isoniazid (for TB)
Human blood group phenotypes
A
B
AB
O
Human blood group genotypes -> phenotype
AA or AO -> A
BB or BO -> B
AB (codominant)-> AB
OO (recessive) -> O
What is another type of antigen that may be present on the RBCs
The Rh (Rhesus) factor
Another name for Rhesus factor
D antigen
What alleles are responsible for the Rh factor?
Rh+ or D (dominant)
rh- or d (recessive)
