Bacterial Cell Wall Flashcards
On the basis of typical structure, composition and Gram staining the bacterial cells are classified into:
- Gram positive bacterial cell wall
- Gram negative bacterial cell wall
*cell wall mainly composed of peptidoglycan and teichoic acid
Cell wall of Gram positive bacteria
• Peptidoglycan comprises up ot 50% of the cell wall material.
Cell wall of Gram positive bacteria
- Peptidoglycan layer si 15-50 nm thick.
Cell wall of Gram positive bacteria
- ——— are stained with dark blue or violet by Gram staining.
Cell wall of Gram positive bacteria
• Composed of peptidoglycan, and outer membrane.
Cell wall of Gram negative bacteria
• Peptidoglycan comprises 5-10% of the wall material
Cell wall of Gram negative bacteria
• Thickness 2-6 nm
Cell wall of Gram negative bacteria
- Outer membrane components: lipoprotein, phospholipid and lipopolysaccharide (LPS; endotoxin).
Cell wall of Gram negative bacteria
• This membrane has special channels, consisting of protein molecules called porins.
Cell wall of Gram negative bacteria
•Cell wall of Gram negative bacteria -
This membrane has special channels, consisting of protein molecules caled
porins
*Gram staining: cannot retain the crystal violet stain, instead take up the counterstain and appeared as pink
Cell wall of Gram negative bacteria
Thicker
Thinner
Grampositive
Gramnegative
40-65 sheets
1-2 sheets
Grampositive
Gramnegative
Varieties of amino acids:
Few
Several
Grampositive
Gramnegative
