Antibiotics work by affecting things that bacterial cells have but human cells don't. For example, human cells do not have cell walls, while many types of bacteria do. The antibiotic penicillin works by keeping a bacterium from building a cell wall.
The Antibiotics work at 3 levels,the first level is at Gene Expression of Bacteria,The gene expression of Bacteria is three step process where we see the flow of Information from DNA to RNA to Protein ,we see the DNA ,Transfers its information into mRNA molecules through a process called Transcription
and from the information of mRNA molecule, the bacteria produces a Protein in the process of Translation.
When both of the processes are stopped by Antibiotics the cell ceases to exist and also the DNA replication of Bacteria is halted by some Antibiotics….
Another novel, working of Antibiotics is that they Inhibit the cell wall synthesis of Bacteria……We humans don’t have cell wall in our cells ,,, so the cell wall becomes easy target of Antibiotics .
And finally there are some antibiotics like Sulfa antibiotics that inhibit that inhibit the folate synthesis in Bacteria by competitive inhibition of enzymes.
Antibiotics like Rifampicin , clindimycin , Beta Lactam , Pencillin and Chloramphenicol affect the bacteria growth and processes at various levels.
