Bacteria without cell wall peptidoglycan

Several differences exist between bacterial and human cells, and these differences form the basis for selective toxicity of the antibacterial drugs (Figure 11-1). First, bacteria have a unique outermost layer, a cell wall that is not found in any human cell. A specific layer within the cell wall, called the peptidoglycan, is necessary for the bacterium s structural integrity without it the bacterium lyses and dies. Several antibacterial drugs act by inhibiting synthesis of the cell wall, specifically the peptidoglycan. 

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