Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
NCBI PubMed ID: 22522903Publication DOI: 10.1128/JB.00329-12Journal NLM ID: 2985120RPublisher: American Society for Microbiology
Correspondence: Juan M. Tomás <jtomas
ub.edu>
Institutions: Departamento de Microbiologia, Facultad de Biologia, Universidad de Barcelona, Barcelona, Spain
The presence of cell-bound K1 capsule and K1 polysaccharide in culture supernatants was determined in a series of in-frame nonpolar core biosynthetic mutants from Escherichia coli KT1094 (K1, R1 core lipopolysaccharide [LPS] type) for which the major core oligosaccharide structures were determined. Cell-bound K1 capsule was absent from mutants devoid of phosphoryl modifications on L-glycero-D-manno-heptose residues (HepI and HepII) of the inner-core LPS and reduced in mutants devoid of phosphoryl modification on HepII or devoid of HepIII. In contrast, in all of the mutants, K1 polysaccharide was found in culture supernatants. These results were confirmed by using a mutant with a deletion spanning from the hldD to waaQ genes of the waa gene cluster to which individual genes were reintroduced. A nuclear magnetic resonance (NMR) analysis of core LPS from HepIII-deficient mutants showed an alteration in the pattern of phosphoryl modifications. A cell extract containing both K1 capsule polysaccharide and LPS obtained from an O-antigen-deficient mutant could be resolved into K1 polysaccharide and core LPS by column chromatography only when EDTA and deoxycholate (DOC) buffer were used. These results suggest that the K1 polysaccharide remains cell associated by ionically interacting with the phosphate-negative charges of the core LPS.
Lipopolysaccharide, biosynthesis, Escherichia coli
Structure type: homopolymer
Location inside paper: p.3356
Trivial name: colominic acid sodium salt, colominic acid, type B polysaccharide, polysialic acid, PSA, oligosaccharide repeating unit, α-2,8-linked polysialic acid
Compound class: CPS, O-polysaccharide, K-antigen, O-antigen
Contained glycoepitopes: IEDB_136794,IEDB_141115,IEDB_142352,IEDB_146100,IEDB_149174,IEDB_150072,IEDB_150937,IEDB_153199,IEDB_226810,IEDB_558870,IEDB_983929,SB_170,SB_171,SB_172,SB_35,SB_42,SB_84
Methods: 13C NMR, 1H NMR, NMR-2D, GC-MS, SDS-PAGE, ELISA, ESI-MS, composition analysis, methanolysis, genetic methods
Biosynthesis and genetic data: genetic data
NCBI Taxonomy refs (TaxIDs): 1392869Reference(s) to other database(s): GTC:G30588ZL, GlycomeDB:
677
Show glycosyltransferases
There is only one chemically distinct structure:
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