I want to know about the different mode of actions of antibiotic?

Answer 1

1- Cell Wall Synthesis Inhibitors:

Bacteria contain peptidoglycan that is highly essential in maintaining the cell wall structure. Cell wall synthesis inhibitors such as beta-lactams, cephalosporins and glycopeptides block the ability of microorganisms to synthesize their cell wall by inhibiting the synthesis of peptidoglycan.

2- Interfering with Protein Synthesis:

These classes of antibiotics inhibit the protein synthesis machinery in the cell. Some examples include tetracyclines, chloramphenicol, aminoglycosides and macrolides.

3- Cell Membrane Inhibitors:

Antibiotics such as polymyxins disrupt the integrity and structure of cell membranes, thereby killing them. These set of antibiotics are mostly effective on gram negative bacteria because these are the bacteria that contain a definite cell membrane.

4- Effect on Nucleic Acids:

DNA and RNA are extremely essential nucleic acids present in every living cell. Antibiotics such as quinolones and rifamycins bind to the proteins that are required for the processing of DNA and RNA, thus blocking their synthesis and thereby affecting the growth of the cells.

5- Competitive Inhibitors:

Also referred to as anti-metabolites or growth factor analogs, these are antibiotics that competitively inhibit the important metabolic pathways occurring inside the bacterial cell. Important ones in this class are sulfonamides such as Gantrisin and Trimethoprim.