Cell wall of Gram negative bacteria
Cell wall of Gram negative bacteria is more rigid and thick then Gram postive bacteria.
It is made up of two layers
1. Peptidoglycan
2. Outer cell wall layer

1. Peptidoglycan
- It is present in between outer wall layer and cell membrane.
- The structure is similar as gram positive cell wall.
- There are some minor differences in the Gram positive and Gram negative peptidoglycan structure.
- The differences are as follows:-
- The third amino acid of tetrapeptide side chainin Gram positive cell wall is L-lysin which is replaced by Mesodiaminopimilic acid in Gram negative cell wall.
- All N-acetymuramic acid molecules are not linked to tetrapeptide side chain.
- Cross bridges are not made up of glycin molecule they are made up of peptide bond.