STRUCTURE OF BACTERIA

The structure of a typical bacterium is illustrated in Figure 2-3,

and the important features of each component are presented in.

The cell wall is the outermost component common to all bac

teria (except Mycoplasma species, which are bounded by a cell membrane, not a cell wall). Some bacteria have surface features

external to the cell wall, such as capsule, flagella, and pili, which

are less Common components and are discussed next.

The cell wall is located external to the cytoplasmic mem-

brane and is composed of peptidoglycan. The

peptidoglycan provides structūraf support and maintains the

characteristic shape of the cell.