Gram-positive cell wall The Gram-positive cell wall has a peptidoglycan layer that is relatively thick(ca. 40 nm) and comprises approximately 90% of the cell wall. The cell walls of most Gram-positive eubacteria also have teichoic acids Peptidoglycan structure Teichoic acid Cell wall (peptidoglycan) C membrane Teichoic acid structure
The Gram-positive cell wall has a peptidoglycan layer that is relatively thick (ca. 40 nm) and comprises approximately 90% of the cell wall. The cell walls of most Gram-positive eubacteria also have teichoic acids. Gram-positive cell wall
Structure of the repeating unit in Peptidoglycan Peptidoglycan is composed of two sugar derivatives, N acetylglucosamine (NAG) and N-acetylmuramic acid (NAM), and a small group of amino acids consisting of L-alanine, D-alanine, D-glutamic acid, and either lysine or diaminopimelic acid DAP) These constituents are baL connected to form a repeating structure, the glycan tetrapeptide ●:4 ●争● 净参●
Structure of the Repeating Unit in Peptidoglycan These constituents are connected to form a repeating structure, the glycan tetrapeptide. Peptidoglycan is composed of two sugar derivatives, Nacetylglucosamine (NAG) and N-acetylmuramic acid (NAM), and a small group of amino acids consisting of L-alanine, D-alanine, D-glutamic acid, and either lysine or diaminopimelic acid (DAP)
Structure of the Repeating Unit in Peptidoglycan and the Manner in Which the Peptide and Glycan Units are Connected N-Acetylglucosamine ( N-Acetylmuramic acid M) CH2OH CHOH OH B(7 H,B01,4 H C=o C=o Lysozyme-sensitive CH3 HC-CH3 CH3 bond H3C-CH L-Alanine CH2-CH2 -CH-COOH D-Glutamic acid HOO一C-cH2-CH2CH2-CH Meso-diaminopimelic acid H3C-CH--COOH D-Alanine
Peptide and glycan units are connected in formation of the peptidoglycan sheet I Gly L-Lys
Peptide and glycan units are connected in formation of the peptidoglycan sheet
Teichoic acids Gram-positive Bacteria frequently have acidic polysaccharides called teichoic acids attached to their cell wall. The term teichoic acids includes all wall membrane, or capsular polymers containing glycerophosphate or ribitol phosphate residues. These polyalcohols are connected by phosphate esters and usually have other sugars and D-alanine attached
Gram-positive Bacteria frequently have acidic polysaccharides called teichoic acids attached to their cell wall. The term teichoic acids includes all wall, membrane, or capsular polymers containing glycerophosphate or ribitol phosphate residues. These polyalcohols are connected by phosphate esters and usually have other sugars and D-alanine attached. Teichoic acids