Difference between the Cell Wall of Gram Positive and Gram Negative Bacteria

Most of the bacterial cells are surrounded by a thick rigid cell wall. The cell wall provides shape to the cell and protects the bacteria from changes in the osmotic pressure. Peptidoglycan (murein) is the principal component of the bacterial cell wall and it is responsible for the shape and extreme tough nature of the cell wall.

Based on the characteristics of the cell wall, the bacterial cells are classified into Gram Positive and Gram Negative, primarily based on the classical staining reaction called Gram Staining. In the previous post we have discussed about the Similarities and Differences between Gram Positive and Gram Negative Bacteria. Both Gram positive and Gram negative bacterial possess cell wall, however, their structural organization, chemical and physical properties varies. In general, the cell wall of Gram positive bacteria has simpler chemical structures compared to the Gram negative bacteria.

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The present post discusses the Differences between the Cell Wall of Gram positive and Gram negative bacteria with a comparison table.

Difference between Gram Positive and Gram Negative Cell Wall

Comparison of the Cell Wall of Gram Positive and Gram Negative Bacteria

Difference between the Cell Wall of Gram Positive and Gram Negative Bacteria

CharacterGram Positive BacteriaGram Negative Bacteria
Gram Stained Bacterial Cells

Gram Stain Anthrax.jpg

Pseudomonas aeruginosa Gram.jpg

Reacting to Gram stainingRetain the crystal violet stain (primary stain) and appear in purple under microscopeDoes not retain the crystal violet stain, appear as pink with safranin (counter stain)
Composition of cell wallThe cell wall primarily composed of peptidoglycanCell wall contain three main components – (1) Lipopolysaccharides, (2) Lipoproteins and (3) Peptidoglycan
Cell Wall of BacteriaGram Positive Vs Gram Negative BacteriaBacterial Cell wall Structure
Thickness of the cell wallComparatively thick and homogenous cell wall.Comparatively thin and heterogeneous cell wall.
7.5 - 12 nm in thickness
Peptidoglycan layerComparatively thick layerThin layer
Lipid ContentLess lipid content, 1 – 4%Comparatively more lipid content, 11 – 22%
Teichoic acidTeichoic acid presentTeichoic acid absent
Amino acid diversityVery less amino acid diversityHigh amino acid diversity
Aromatic amino acidsAbsentPresent
Action as endotoxinNot act as endotoxinActs as endotoxin
Sulfur containing amino acidsAbsent in the cell wallPresent in the cell wall
Treated with lysosomeProduce protoplastProduce spheroplast
LPSLPS absentLPS present
Outer membraneAbsentPresent
PorinsAbsent (very rarely present)Present

Difference between Gram Positive and Gram Negative Cell Wall

Gram negative cell wall

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@. Difference between Gram Positive and Gram Negative Bacteria

@. Compare Archaea, Bacteria and Eukarya

@. Difference between Peptidoglycan and Pseudopeptidoglycan

@. Bacterial Cell Surface Appendages (Flagella, Fimbriae and Pili)

@. Bacterial Endospores: Properties, Structure and Formation

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  1. Hello Sir!
    I want to inform you that whenever EBC has given us any comparison table contents ..
    We are not able to open it full display of it..
    It never displayed full content that is given by you..
    Can you please let me know the way how to do it if I am not able to see it or from the site it is not displayed ..

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