Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
NCBI PubMed ID: 15090514Journal NLM ID: 2985120RPublisher: American Society for Microbiology
Correspondence: romeo
microbio.emory.edu
Institutions: Department of Microbiology and Immunology, Emory University School of Medicine, 3105 Rollins Research Center, 1510 Clifton Road NE, Atlanta, GA 30322, USA
Production of a polysaccharide matrix is a hallmark of bacterial biofilms, but the composition of matrix polysaccharides and their functions are not widely understood. Previous studies of the regulation of Escherichia coli biofilm formation suggested the involvement of an unknown adhesin. We now establish that the pgaABCD (formerly ycdSRQP) locus affects biofilm development by promoting abiotic surface binding and intercellular adhesion. All of the pga genes are required for optimal biofilm formation under a variety of growth conditions. A pga-dependent cell-bound polysaccharide was isolated and determined by nuclear magnetic resonance analyses to consist of unbranched β-1,6-N-acetyl-D-glucosamine, a polymer previously unknown from the gram-negative bacteria but involved in adhesion by staphylococci. The pga genes are predicted to encode envelope proteins involved in synthesis, translocation, and possibly surface docking of this polysaccharide. As predicted, if poly-β-1,6-GlcNAc (PGA) mediates cohesion, metaperiodate caused biofilm dispersal and the release of intact cells, whereas treatment with protease or other lytic enzymes had no effect. The pgaABCD operon exhibits features of a horizontally transferred locus and is present in a variety of eubacteria. Therefore, we propose that PGA serves as an adhesin that stabilizes biofilms of E. coli and other bacteria.
biosynthesis, gene, regulation, polysaccharides, adhesin, biofilms, phylogeny, PNAG
Structure type: homopolymer
Location inside paper: abstract
Trivial name: poly-β-1,6-GlcNAc (PGA), biofilm, poly-b-(1-6)-N-acetyl-D-glucosamine (PNAG), poly-β-N-acetyl-glucosamine (PNAG), PNAG, poly-N-acetylglucosamine, PNAG
Compound class: CPS, EPS, O-polysaccharide, glucan, polysaccharide
Contained glycoepitopes: IEDB_135813,IEDB_137340,IEDB_141807,IEDB_151531,IEDB_753248
Biosynthesis and genetic data: genetic data
Comments, role: adhesin that stabilizes biofilms of E.coli and other bacteria
Related record ID(s): 7481, 8999
NCBI Taxonomy refs (TaxIDs): 562Reference(s) to other database(s): GTC:G36952FI, GlycomeDB:
11210
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
report error