Question

Briefly explain how each of the following mechanisms of action inhibits or kills bacteria and give examples of each:

Inhibition of cell wall biosynthesis

Inhibition of protein synthesis

Inhibition of membrane function.

Inhibition of nucleic acid synthesis

Inhibition of metabolic pathways

Inhibition of ATP synthase

Answer 1

Answer

Inhibition of cell wall biosynthesis

These drugs act by inhibiting peptydoglycon (from which cell wall made of).These drugs make cell more susceptible to osmotic lysis.example penicillin, cephalosporin,monobactum.

Inhibition of protein synthesis

Some drugs bind to the 30S part of ribosomal protein thus inhibit protein synthesis.eg tetracycline blocks the binding of tRNA.

Aminoglycosides impairs the proof reading.

Some drugs bind to the 50 S part of ribosomal proteins thus inhibit protein synthesis.eg macrolides,clindamycin,linezolid,chloramphenical.

Inhibition of membrane function

These drugs disrupts the innner and outer membrane by Interacting with lipopolysaccharides that is component of outer membrane in order to killing bacterial cell.

Example polymyxins

Inhibition of nucleic acid synthesis

Metronidazole It interfere with DNA replication in target cell.

Rifamycin it blocks the Transcription process by blocking enzyme RNA polymerase.

Fluoroquinolones inhibits the DNA gyrase activity thus blocks DNA replication so kill the cell.

Inhibition of metabolic pathway

These drugs interfering with folic acid synthesis by inhibiting the enzyme involved in production of dihydro folic acid.example Sulphonamides.

Also involve in the production of tetrahydro folic acid by inhibiting enzyme.example trimethoprim.

Interfere with the synthesis of mycolic acid.example Isoniazid.

Inhibition of ATP synthese

These drugs interfere with the function of ATP synthase.Specific mechanism of thses drugs yet to be elucidated.Perhaps it reduces the ATP production by interrupting with oxidative phosphorylation.

Example Diaryquinolones.