GENERAL KNOWLEDGE

Detailed explanation-1: -Penicillins have been shown to inhibit bacterial cell wall synthesis, and interact with penicillin binding proteins, leading to bacterial lysis. These two mechanisms, the former more than the latter are believed to be responsible for their therapeutic potential.

Detailed explanation-2: -The antibiotic penicillin works by keeping a bacterium from building a cell wall. Bacteria and human cells also differ in the structure of their cell membranes and the machinery they use to build proteins or copy DNA. Some antibiotics dissolve the membrane of just bacterial cells.

Detailed explanation-3: -Penicillin acts by inhibiting the transpeptidase enzyme-it mimics a peptidoglycan chain and an ester is formed that joins the penicillin to the enzyme. As the penicillin group is so large, it prevents attack of a nucleophile at the ester carbonyl and so the ester does not react with the second peptidoglycan chain.

Detailed explanation-4: -Antibiotics such as beta-lactams-penicillin, methicillin, cephalosporin-and non-beta-lactams such as vancomycin, attack the peptidoglycan cell wall to quell bacterial infections.