Teichoic acids are polymers of glycerol or ribitol linked via phosphodiester bonds. These acids can be found in the cell wall of gram-positive bacteria, such as Staphylococci, Streptococci, Bacillus, Clostridium, Corynebacterium and Listeria, and appear to extend to the surface of the peptidoglycan layer. Teichoic acids are not found in the gram-negative bacteria. They can be either covalently bonded to N-acetylmuramic acid of the peptidoglycan layer or linked to the plasma membrane lipids found in the cytoplasmic membrane. The combined units comprised of teichoic acids and lipids are referred to as lipoteichoic acids. Teichoic acids are negatively charged and therefore contribute to the negative charge of the gram-positive cell wall. They may also provide structural support for the cell wall. Glycerol, also well known as glycerin and glycerine, and less commonly as propane-1,2,3-triol, 1,2,3-propanetriol, 1,2,3-trihydroxypropane, glyceritol, and glycyl alcohol, is a colorless, odorless, hygroscopic, and sweet-tasting viscous liquid. ... Ribitol or Adonitol is a crystalline pentose alcohol (C5H12O5) formed by the reduction of ribose. ... Diagram of phosphodiester bonds between nucleotides A phosphodiester bond is a group of strong covalent bonds between the phosphorus atom in a phosphate group and two other molecules over two ester bonds. ... A cell wall is a fairly rigid layer surrounding a cell, located external to the cell membrane, that provides the cell with structural support, protection, and a filtering mechanism. ... Gram-positive bacteria are those that are stained dark blue or violet by gram staining, in contrast to gram-negative bacteria, which are not affected by the stain. ... Species S. aureus Staphylococcus (in Greek staphyle means bunch of grapes and coccos means granule) is a genus of gram-positive bacteria. ... Species S. pneumoniae S. pyogenes S. viridans Streptococcus is a genus of spherical, Gram-positive bacteria of the phylum Firmicutes. ... Species Bacillus anthracis Bacillus cereus Bacillus coagulans Bacillus natto Bacillus subtilis Bacillus thuringiensis etc. ... Species Clostridium acetobutylicum Clostridium aerotolerans Clostridium botulinum Clostridium colicanis Clostridium difficile Clostridium formicaceticum Clostridium novyi Clostridium perfringens Clostridium sordelli Clostridium tetani Clostridium piliforme Clostridium tyrobutyricum etc. ... Species See text. ... Species Listeria monocytogenes Listeria ivanovii Listeria innocua Listeria welshimeri Listeria seegligeri Listeria grayi Listeria innocua Listeria is a bacterial genus containing six species. ... Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms a homogeneous layer outside the plasma membrane of eubacteria. ... Bacteria that are Gram-negative are not stained dark blue or violet by Gram staining, in contrast to Gram-positive bacteria. ... Figure 1: Basic lipid structure. ... Drawing of a cell membrane A component of every biological cell, the cell membrane (or plasma membrane) is a thin and structured bilayer of phospholipid and protein molecules that encapsulate the cell. ... Lipoteichoic acid (LTA) is a surface-associated adhesion amphiphile from Gram-positive bacteria and regulator of autolytic wall enzymes (muramidases). ...