Peptidoglycan lattice

Figure 8. Penicillin (right) and the normal substrate for the enzyme that is inhibited by penicillin. Peptidoglycan is normally cross-linked in the bacterial cell wall to create a tough lattice of covalent bonds. However, if penicillin binds to and inhibits the enzymes needed for the cross-linking process, the bacteria will not survive.

Despite the numerous variations encountered in the peptidoglycan backbone, the peptide side chains and the bridge linking the chains, the overall structure of the peptidoglycan is essentially constant. It forms a cross-linked lattice structure which is responsible for the shape and integrity of the bacterial cell wall (Figure 1.1). 

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