Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
NCBI PubMed ID: 12618464Journal NLM ID: 2985120RPublisher: American Society for Microbiology
Correspondence: Kevin.Gardner

UTSouthwestern.edu
Institutions: Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, USA, Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038, Department of Microbiology and Immunology, F. Edward Herbert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland 208142, Department of Bio-Organic Chemistry, Bijvoet Center, Utrecht University, 3508 TB Utrecht, The Netherlands
Phosphoglyceride-linked enterobacterial common antigen (ECA(PG)) is a cell surface glycolipid that is synthesized by all gram-negative enteric bacteria. The carbohydrate portion of ECA(PG) consists of linear heteropolysaccharide chains comprised of the trisaccharide repeat unit Fuc4NAc-ManNAcA-GlcNAc, where Fuc4NAc is 4-acetamido-4,6-dideoxy-D-galactose, ManNAcA is N-acetyl-D-mannosaminuronic acid, and GlcNAc is N-acetyl-D-glucosamine. The potential reducing terminal GlcNAc residue of each polysaccharide chain is linked via phosphodiester linkage to a phosphoglyceride aglycone. We demonstrate here the occurrence of a water-soluble cyclic form of enterobacterial common antigen, ECA(CYC), purified from Escherichia coli strains B and K-12 with solution nuclear magnetic resonance (NMR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and additional biochemical methods. The ECA(CYC) molecules lacked an aglycone and contained four trisaccharide repeat units that were nonstoichiometrically substituted with up to four O-acetyl groups. ECA(CYC) was not detected in mutant strains that possessed null mutations in the wecA, wecF, and wecG genes of the wec gene cluster. These observations corroborate the structural data obtained by NMR and ESI-MS analyses and show for the first time that the trisaccharide repeat units of ECA(CYC) and ECA(PG) are assembled by a common biosynthetic pathway.
NMR, biosynthesis, antigen, common, chemistry, Bacterial, genetics, growth & development, metabolism, potential, strain, Non-U.S.Gov't, terminal, polysaccharide, trisaccharide, carbohydrate, cell, chain, linked, form, Escherichia, Escherichia coli, acid, antigens, immunology, enterobacterial common antigen, bacteria, electrospray, spectrometry, linkage, common antigen, cyclic, enterobacterial, identification, biochemistry, Magnetic Resonance Spectroscopy, nuclear, nuclear magnetic resonance, resonance, spectroscopy, surface, Gram-negative, mutation, purified, methods, glycolipid, reducing, heteropolysaccharide, linear, occurrence, phosphodiester, solution, Enterobacteriaceae, U.S.Gov't, electrophoresis, isolation & purification, Mass, Electrospray Ionization, P.H.S., Research Support, Basic Helix-Loop-Helix Transcription Factors, Trans-Activators, Transcription Factors
Structure type: cyclic polymer repeating unit ; n=4, 2430
Location inside paper: p.1995
Trivial name: Enterobacterial common antigen
Contained glycoepitopes: IEDB_137340,IEDB_141807,IEDB_151531,IEDB_885813
Methods: NMR, ESI-MS, FACE
Biosynthesis and genetic data: genetic data, biosynthetic data
NCBI Taxonomy refs (TaxIDs): 37762,
83333Reference(s) to other database(s): GTC:G98598EB, GlycomeDB:
27070
Show glycosyltransferases
There is only one chemically distinct structure: