Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
Journal NLM ID: 2985120RPublisher: American Society for Microbiology
Correspondence: cwhitfie
micro.uoguelph.ca
Institutions: Department of Microbiology, University of Guelph, Guelph, Canada
The 6.6-kb rfb gene cluster from Klebsiella pneumoniae serotype O1 (rfbKpO1) contains six genes whose products are required for the biosynthesis of a lipopolysaccharide O antigen with the following repeating unit structure: 33-b-D-Galf-133-a-D-Galp-13(D-galactan I). rfbFKpO1 is the last gene in the cluster, and its gene product is required for the initiation of D-galactan I synthesis. Escherichia coli K-12 strains expressing the RfbFKpO1 polypeptide contain dual galactopyranosyl and galactofuranosyl transferase activity. This activity modifies the host lipopolysaccharide core by adding the disaccharide b-D-Galf-133-a-D-Galp, representing a single repeating unit of D-galactan I. The formation of the lipopolysaccharide substituted either with the disaccharide or with authentic polymeric D-galactan I is dependent on the activity of the Rfe enzyme. Rfe (UDP-GlcpNAc::undecaprenylphosphate GlcpNAc-1-phosphate transferase) catalyzes the formation of the lipid-linked biosynthetic intermediate to which galactosyl residues are transferred during the initial steps of D-galactan I synthesis. The rfbFKpO1 gene comprises 1,131 nucleotides, and the predicted polypeptide consists of 373 amino acid residues with a predicted Mr of 42,600. A polypeptide with an Mr of 42,000 was evident in sodium dodecyl sulfate-polyacrylamide gels when rfbKpO1 was expressed behind the T7 promoter. The carboxyterminal region of RfbFKpO1 shares similarity with the carboxy terminus of RfpB, a galactopyranosyl transferase which is involved in the synthesis of the type 1 O antigen of Shigella dysenteriae.
Lipopolysaccharide, biosynthesis, antigen, LPS, role, serotype, O-antigen, O antigen, Klebsiella, Klebsiella pneumoniae, D-galactan, initiation
Structure type: oligomer
Location inside paper: Fig.3
Aglycon: Escherichia coli K-12 core
Contained glycoepitopes: IEDB_135813,IEDB_136095,IEDB_136906,IEDB_137340,IEDB_137472,IEDB_141794,IEDB_141807,IEDB_151528,IEDB_151531,IEDB_190606,SB_7
Methods: genetic methods, biochemical methods
Biosynthesis and genetic data: genetic data, biosynthesis data
Comments, role: RfpF-modified core
Related record ID(s): 6533, 6649
NCBI Taxonomy refs (TaxIDs): 83333Reference(s) to other database(s): GTC:G54606KH, GlycomeDB:
35069
Show glycosyltransferases
There is only one chemically distinct structure:
Found 
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