Poly-β-1,6-N-acetylglucosamine exopolysaccharide (PNAG)

Poly-β-1,6-N-acetylglucosamine exopolysaccharide (PNAG) is a linear, insoluble polysaccharide consisting of β-1,6-linked N-acetylglucosamine subunits, partially deacetylated in its native biofilm-structural form (dPNAG)[1][2][3][5]. It is synthesized by major pathogens including *Escherichia coli*, *Staphylococcus aureus*, and *Staphylococcus epidermidis* as a principal component of their biofilm extracellular matrix. PNAG production is catalyzed by multi-component operons (e.g., pgaABCD in Gram-negative bacteria, icaADBC in Gram-positive bacteria), involving glycosyltransferases and deacetylases (such as PgaC/D and IcaA/B). Partial deacetylation is essential for export, biofilm architecture, and adhesion, as well as for evasion of immune responses—biofilm bacteria with dPNAG resist phagocytosis and antimicrobial assault[1][2][3][5]. Due to these properties, PNAG is considered a promising target for antibiofilm therapeutics and vaccines, although no clinically approved drugs directly targeting PNAG are yet available.

Other names

Poly-N-acetylglucosaminePoly-β-1,6-N-acetyl-D-glucosaminePNAGdPNAG (for partially deacetylated form)

Disruption of PNAG synthesis (e.g., by targeting biosynthetic enzymes such as PgaC, PgaD, or IcaA); Inhibition of deacetylation (affecting export and biofilm formation); Antibody-mediated immunity targeting PNAG; Enzymatic degradation of PNAG to disassemble biofilms