PUL ID

PUL0433

PubMed

27645300, Glycoconj J. 2017 Feb;34(1):71-84. doi: 10.1007/s10719-016-9730-y. Epub 2016 Sep 19.

Characterization method

sequence homology analysis, sugar utilization assay, NMR

Genomic accession number

KJ778804

Nucelotide position range

107-12715

Substrate

O-antigen

Loci

AIG62795.1-AIG62806.1

Species

Escherichia coli/562

Degradation or Biosynthesis

biosynthesis

Gene Name

Locus Tag

Protein ID

Gene Position

GenBank Contig Range

EC Number

rmlB - AIG62806.1 107 - 1193 (+) KJ778804.1:214-1300 -
rmlD - AIG62805.1 1192 - 2092 (+) KJ778804.1:1299-2199 -
rmlA - AIG62804.1 2149 - 3028 (+) KJ778804.1:2256-3135 -
rmlC - AIG62803.1 3032 - 3578 (+) KJ778804.1:3139-3685 -
- - AIG62802.1 3595 - 4951 (+) KJ778804.1:3702-5058 -
wzx - AIG62801.1 4955 - 6470 (+) KJ778804.1:5062-6577 -
- - AIG62800.1 6466 - 7600 (+) KJ778804.1:6573-7707 -
wfgH - AIG62799.1 7604 - 8489 (+) KJ778804.1:7711-8596 -
wzy - AIG62798.1 8517 - 9633 (+) KJ778804.1:8624-9740 -
- - AIG62797.1 9652 - 10561 (+) KJ778804.1:9759-10668 -
epsD - AIG62796.1 10563 - 11712 (+) KJ778804.1:10670-11819 -
- - AIG62795.1 11731 - 12715 (+) KJ778804.1:11838-12822 -

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

- 108 - 1193 (+) CDS No
- 1193 - 2092 (+) CDS No
- 2150 - 3028 (+) CDS No
- 3033 - 3578 (+) CDS No
- 3596 - 4951 (+) CDS No
- 4956 - 6470 (+) CDS No
- 6467 - 7600 (+) CDS No
- 7605 - 8489 (+) CDS No
- 8518 - 9633 (+) CAZyme: GT2|GT2_Glycos_transf_2 Yes
- 9653 - 10561 (+) other Yes
- 10564 - 11712 (+) TC: gnl|TC-DB|E8RJP5|9.B.97.1.10 Yes
- 11732 - 12715 (+) CDS No

PUL ID

PUL0433

PubMed

27645300, Glycoconj J. 2017 Feb;34(1):71-84. doi: 10.1007/s10719-016-9730-y. Epub 2016 Sep 19.

Title

Structures and gene clusters of the O-specific polysaccharides of the lipopolysaccharides of Escherichia coli O69 and O146 containing glycolactilic acids: ether conjugates of D-GlcNAc and D-Glc with (R)- and (S)-lactic acid.

Author

Knirel YA, Guo X, Senchenkova SN, Perepelov AV, Liu B, Shashkov AS

Abstract

Based on the O-specific polysaccharides of the lipopolysaccharides (O-polysaccharides, O-antigens), strains of a clonal species Escherichia coli are classified into 184 O serogroups. In this work, structures of the O-polysaccharides of E. coli O69 and O146 were elucidated and gene clusters for their biosynthesis were characterized. The O-polysaccharides were released from the lipopolysaccharides by mild acid hydrolysis and studied by sugar analysis and one- and two-dimensional (1)H and (13)C NMR spectroscopy before and after O-deacetylation. The O146 polysaccharide was also studied by Smith degradation. The O69 and O146 polysaccharides were found to contain ether conjugates of monosaccharides with lactic acid called glycolactilic acids: 2-acetamido-2-deoxy-4-O-[(R)-1-carboxyethyl]-D-glucose (D-GlcNAc4Rlac) and 3-O-[(S)-1-carboxyethyl]-D-glucose (D-Glc3Slac), respectively. Structures of the pentasaccharide repeats of the O-polysaccharides were established, and that of E. coli O69 was found to differ in the presence of D-GlcNAc4Rlac from the structure reported for this bacterium earlier (Erbing C, Kenne L, Lindberg B. 1977. Carbohydr Res. 56:371-376). The O-antigen gene clusters of E. coli O69 and O146 between conserved genes galF and gnd were analyzed taking into account the O-polysaccharide structures established, and functions of putative genes for synthesis of D-Glc3Slac and D-GlcNAc4Rlac and for glycosyltransferases were assigned based on homology with O-antigen biosynthesis genes of other enteric bacteria. It was found that in E. coli and Shigella spp. predicted enolpyruvate reductases of the biosynthesis pathway of glycolactilic acids, LarR and LarS, which catalyze formation of conjugates with (R)- or (S)-lactic acid, respectively, are distinguished by sequence homology and size.