Question

Bacterial cell wall is composed of peptidoglycan, a complex of oligosaccharides and proteins. The oligosaccharide component consists of

• A. linear chain of laternating NAG and NAM linked by $\alpha (1-4)$ linkage
• B. linear chain of glucose linked by $\beta (1-4)$ linkage
• C. linear chain of glucose linked by $\alpha (1-4)$ linkage
• D. linear chains of laternating NAG and NAM linked by $\beta (1-4)$ linkage

Answer 1

The correct option is D linear chains of laternating NAG and NAM linked by $\beta (1-4)$ linkage

Bacterial cell wall

Bacterial cell are protected by the cell wall located immediately outside the cytoplasmic membrane. The cell wall is made up of peptidoglycan which is a complex formed of oligosaccharides and proteins.


The oligosaccharide is formed of a linear chain of alternating monosaccaride units called N-acetylglucosamine (NAG) and N-acetylmuramic acid (NAM) linked by $\beta -1,4$ gkycosidic bonds.

Parallel chains of oligosaccharides are connected by peptide side chains which arise from NAM subunits.