The amoxicillin and the ampicillin are known to degrade the cell wall. both of these antibiotics have β- lactam in their structure. The structure of the ampicillin and the amoxicillin is similar having a single difference at the 4th position of benzene ring. The structure of the amoxicillin have an addition OH or hydroxyl group at the 4th position in the benzene ring.
As the structure of ampicillin and amoxicillin is similar, the bacteria having ampicillin resistance can also show amoxicillin resistance.
MODE OF ACTION OF AMOXICILLIN:
The amoxicillin binds with the pencillin binding proteins, present in the bacterial cell wall. The binding of the amoxicillin inhibits the enzyme transpepetidase, which is an important enzyme for the synthesis of the cell wall. it also inhibit murine hydrolases and inhibit the assembling of cell wall.
The amoxicillin effects the cell walls of the bacteria, as the animals cells do not have cell wall, they only have a cell membrane, the increase in the dose would not effect the animal cell.