Antibitotics - Protein Synthesis Flashcards
What do Antibitotics that target Protein Synthesis do ?
- Target the ribosome to inhibit protein synthesis and, thereby, bacterial cell growth.
- Antibiotics influence the ribosome to inhibit protein synthesis at 5 different sites.
What are the 5 protein synthesis antibitotics ? TP CALM
Tetracycline
- P - protein synthesis
Chloramphenicol
Aminoglycosides
Linezolid
Macrolides
How do tetracyclines work ?
Name a tetracycline and give an adverse effect.
Tetracyclines inhibit protein synthesis by binding to the 30S segment of the ribosome, preventing aminoacyl tRNA (shown in black) from binding to the A site on the 50S segment.
Doxycycline
Photosensitivity
Binds to teeth and bones and causes discolouration in children under 5.
How do aminoglycosides work?
Name one
Give 2 adverse effects.
The aminoglycosides bind irreversibly to the 30S portion of the ribosome, but, as a result, the mRNA codon messages are misread, generating short or abnormal non-functional proteins.
Gentamicin
- Ototoxicity
- Nephrotoxicity
- Needs therapeutic monitoring.
How does Chloramphenicol work?
Give a adverse effects.
Binds to 50S segment on the ribosome, inhibiting the activity of peptidyl transferase enzyme.
- Lipid soluble enough to cross BBB
- Can induce bone marrow depression (Pancytopenia)
- Used for eye ointment.
How to macrolides work ?
Name one
Give some adverse effects
Bind to 50S subunit of the bacterial ribsosome and block translocation.
Erythromycin
-Oral irritant (thrombophlebitis IV)
-HepProlongation of QT interval (arrhythmia)
How do linezolids work ?
Name 2 adverse effects
Binds to 50s A site preventing tRNA from initiating transcription. Inhibits the initiation NOT the elongation of protein synthesis
Adverse Effects
1. Blood disorders
– weekly blood/platelet count
2. Peripheral neuropathy, optic neuropathy, lactic acidosis
(28 days or longer)
