Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Associated disease: infection due to Escherichia coli [ICD11:
XN6P4 
]
NCBI PubMed ID: 17368567Journal NLM ID: 0372516Publisher: Academic Press
Correspondence: wang.892

osu.edu
Institutions: Department of Biochemistry, The Ohio State University, Columbus, OH 43210, USA
The O-antigen gene cluster of Escherichia coli O86:B7 was sequenced previously in our lab. One UDP-hexose 4-epimerase gene (named gne2 in this paper) was found and later characterized to be able to catalyze the interconversion between UDP-GlcNAc/GalNAc and UDP-Glc/Gal with almost equal efficiency. However, sequencing of the flanking gene region upstream of the traditional O-antigen gene cluster revealed an open reading frame (gne1), sharing 100% identity with Gne from E. coli O55, previously identified as UDP-GlcNAc 4-epimerase. Furthermore, we also located the traditional galE gene in the gal operon of O86:B7, which can catalyze the interconversion of UDP-Glc to UDP-Gal. Thus, for the first time, three UDP-hexose 4-epimerases with overlapping substrate specificity were found to coexist in one bacterium. Deletion of gne1 and gne2 in O86:B7 produced two different LPS phenotypes: the gne1 mutant exhibited rough LPS, while the gne2 mutant showed semi-rough LPS phenotype. These findings provide new clues for understanding the mechanism of O-antigen biosynthesis
O-antigen, rough LPS, UDP-hexose 4-epimerase, Semi-rough LPS
Structure type: suggested polymer biological repeating unit
Location inside paper: p.605, fig.1A
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_115013,IEDB_130645,IEDB_130648,IEDB_134627,IEDB_136044,IEDB_136045,IEDB_136906,IEDB_137472,IEDB_137473,IEDB_1391961,IEDB_1391963,IEDB_140125,IEDB_141582,IEDB_141584,IEDB_141794,IEDB_142489,IEDB_143260,IEDB_144562,IEDB_149558,IEDB_150766,IEDB_150948,IEDB_150952,IEDB_151528,IEDB_152212,IEDB_152214,IEDB_153553,IEDB_174333,IEDB_190606,IEDB_241096,IEDB_461710,IEDB_461718,IEDB_461719,IEDB_549285,IEDB_885822,IEDB_918314,SB_148,SB_154,SB_165,SB_166,SB_187,SB_195,SB_23,SB_24,SB_7,SB_8,SB_86,SB_87,SB_88
Methods: GLC-MS, GLC, serological methods, genetic methods, CE-ESI-MS
Enzymes that release or process the structure: GalE, Gne1, Gne2
Biosynthesis and genetic data: genetic data
Synthetic data: enzymatic
Related record ID(s): 10715, 11314, 11375, 20507, 22686, 30311
NCBI Taxonomy refs (TaxIDs): 2162909Reference(s) to other database(s): GTC:G64231CD, GlycomeDB:
27794
Show glycosyltransferases
There is only one chemically distinct structure: