polyNacetylglucosamine
PolyNacetylglucosamine, often abbreviated as PNG or PNAG, is a high-molecular-weight anionic polysaccharide composed of N-acetylglucosamine monomers. It is a common and abundant component of bacterial cell walls, particularly in Gram-positive bacteria, and plays a crucial role in maintaining cell envelope integrity and structure. PNG is also found in some eukaryotic organisms, including fungi and insects, where it contributes to exoskeletal strength.
The structure of PNG is a linear polymer of N-acetylglucosamine units linked by beta-(1,4) glycosidic bonds.
In bacteria, PNG is synthesized and exported to the cell surface, where it forms a mesh-like structure