Dictionary » P » Peptidoglycan



noun, plural: peptidoglycans

(1) A glycan (a polysaccharide) attached to short cross-linked oligopeptides in the cell wall of eubacteria

(2) A crystal lattice structure in the bacterial cell wall that is made up of linear chains of alternating amino sugars, namely N-acetylglucosamine and N-acetylmuramic acid, and short peptide chains of three to five amino acids (attached to the N-acetylmuramic acid). The peptide chains form cross-links between them resulting in a 3D mesh-like structure.

(3) A polymer that serves a structural role in the bacterial cell wall, giving structural strength, as well as counteracting the osmotic pressure of the cytoplasm. It is also involved in binary fission during bacterial cell reproduction.


The peptidoglycan layer of Gram-positive bacteria is substantially thicker than that of Gram-negative bacteria. Hence, Gram-positive bacteria are more susceptible to certain antimicrobial agents like penicillin and other β-lactam antibiotics that work by inhibiting the formation of peptidoglycan cross-links thereby weakening their cell wall.

Synonym: mucopeptide, murein.
See also: cell wall (bacteria).

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Bacterial Taxonomy

... taxonomic groups. Here it goes. Bacteria in General Bacteria reproduce asexually, with the most common method being binary fission. They all have peptidoglycan cell walls , unlike archaea. Deeply Branching Bacteria The major phyla of the deeply branching bacteria are Chlorflexi, Deinococcus-Thermus, ...

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by wildfunguy
Sat Oct 19, 2013 6:12 pm
Forum: Microbiology
Topic: Bacterial Taxonomy
Replies: 3
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by billyfisher100
Sat Jan 21, 2012 1:26 pm
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Reasons for Skepticism on the Endosymbiosis?

... see some examples here . In order for mitochondria to resemble bacterial membranes, they should share characteristics such as a cell wall with peptidoglycan and lipopolysaccharides, gram-staining and antibiotic sensitivity. Some effects of antibiotics have been seen with both bacteria and mitochondria, ...

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by SuperfluousAvatar
Thu Jan 12, 2012 7:43 pm
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microbiology-archeobacteria and eubacteria

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by bellyjelly
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How do gram-positive build proton gradient? No periplasm..

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