What are the differences between gram positive and gram-negative cell walls?

Question

Accepted Answer

Basis of differentiation

Gram positive cell wall

Gram negative cell wall

Definition

Refers to the cell wall of Gram positive bacteria

Refers to the cell wall of Gram negative bacteria

Number of peptidoglycan layers

Multilayered peptidoglycan layer

Single peptidoglycan layer

Thickness of peptidoglycan layer

Thick peptidoglycan layer about 15 to 80 nm

Thin peptidoglycan layer about 8-12 nm

Outer membrane

Absent

Present

Teichoic acids

Present

Absent

Porin proteins

Absent

Present in the outer membrane

Periplasmic space

Negligible or absent

Present

Lipopolysaccharide concentration

Low

High

Outcome of Gram staining

Stains purple in color

Stains pink in color

Retention of crystal violet

Retains crystal violet

Does not retain crystal violet

Resistance against antibiotics

Less resistant

Highly resistant

Toxicity

Less toxic

More toxic

Basis of differentiation	Gram positive cell wall	Gram negative cell wall
Definition	Refers to the cell wall of Gram positive bacteria	Refers to the cell wall of Gram negative bacteria
Number of peptidoglycan layers	Multilayered peptidoglycan layer	Single peptidoglycan layer
Thickness of peptidoglycan layer	Thick peptidoglycan layer about 15 to 80 nm	Thin peptidoglycan layer about 8-12 nm
Outer membrane	Absent	Present
Teichoic acids	Present	Absent
Porin proteins	Absent	Present in the outer membrane
Periplasmic space	Negligible or absent	Present
Lipopolysaccharide concentration	Low	High
Outcome of Gram staining	Stains purple in color	Stains pink in color
Retention of crystal violet	Retains crystal violet	Does not retain crystal violet
Resistance against antibiotics	Less resistant	Highly resistant
Toxicity	Less toxic	More toxic