ki.se (E. K. H. Schweda)
Clinical Research Centre, Karolinska Institutet and Sodertorn University, NOVUM, S-141 86 Huddinge, Sweden
Lipopolysaccharide (LPS) of Haemophilus influenzae comprises a conserved tri-l-glycero-d-manno-heptosyl inner-core moiety (L-α-D-Hepp-(1→2)-[PEtn→6]-L-α-D-Hepp-(1→3)-[β-D-GlcIp-(1→4)]-L-α-D-Hepp-(1→5)-α-Kdop) to which addition of β-D-Glcp to O-4 of GlcI in serotype b strains is controlled by the gene lex2B. In non-typeable H. influenzae strains 1124 and 2019, however, a β-D-Galp is linked to O-4 of GlcI. In order to test the hypothesis that the lex2 locus is involved in the expression of β-D-Galp-(1→4-β-D-Glcp-(1→ from HepI, lex2B was inactivated in strains 1124 and 2019, and LPS glycoform populations from the resulting mutant strains were investigated. Detailed structural analyses using NMR techniques and electrospray-ionisation mass spectrometry (ESIMS) on O-deacylated LPS and core oligosaccharide material (OS), as well as ESIMS(n) on permethylated dephosphorylated OS, indicated both lex2B mutant strains to express only β-D-Glcp extensions from HepI. This provides strong evidence that Lex2B functions as a galactosyltransferase adding a β-D-Galp to O-4 of GlcI in these strains, indicating that allelic polymorphisms in the lex2B sequence direct alternative functions of the gene product
13C NMR, 1H NMR, methylation, GLC-MS, sugar analysis, dephosphorylation, ESI-MS, mild acid hydrolysis, de-O-acylation with hydrazine, NMR-1D, CE-ESI-MS
In published Table 2, Hep-I C7 (62.8) seems to be erroneously presented as C6.
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6 C7
5,3,2,2,4,4,3,2 Ac
5,3,2,2,4,4,3 bDGalpN 104.3 53.4 71.7 68.6 ? ?
5,3,2,2,4,4 aDGalp 101.3 ? 79.7 69.8 ? ?
5,3,2,2,4 bDGalp 104.3 71.7 72.8 78.3 76.3 ?
5,3,2,2 bDGlcp 102.6 74.0 75.4 79.7 75.5 64.1
5,3,2,3,0 xXEtN 62.5 40.4
5,3,2,3 P
5,3,2 aXLDmanHepp 100.7 77.7 75.3 ? ? ? ?
5,3,6,0 xXEtN 61.5 40.4
5,3,6 P
5,3 aXLDmanHepp 99.5 79.7 ? ? ? 75.6 ?
5,4,6,0 xXCho 60.1 66.5 55.0
5,4,6 P
5,4 bDGlcp 104.2 74.0 77.0 75.4 75.6 65.2
5 aXLDmanHepp 97.6 ? ? 74.3 ? ? 62.8
4,0,0 xXEtN
4,0 P
4 P
aXKdop
1H NMR data:
Linkage Residue H1 H2 H3 H4 H5 H6 H7
5,3,2,2,4,4,3,2 Ac
5,3,2,2,4,4,3 bDGalpN 4.70 4.02 3.82 4.02 ? ?
5,3,2,2,4,4 aDGalp 5.00 3.97 4.05 4.33 ? ?
5,3,2,2,4 bDGalp 4.59 3.68 3.85 4.14 3.88 ?
5,3,2,2 bDGlcp 4.77 3.47 3.77 3.76 3.67 3.88-4.07
5,3,2,3,0 xXEtN 4.29 3.37
5,3,2,3 P
5,3,2 aXLDmanHepp 5.18 4.46 4.42 4.13 ? ? ?
5,3,6,0 xXEtN 4.24 3.31
5,3,6 P
5,3 aXLDmanHepp 5.75 4.37 ? ? ? 4.66 ?
5,4,6,0 xXCho 4.46 3.70 3.23
5,4,6 P
5,4 bDGlcp 4.60 3.47 3.53 3.66 3.61 4.23-4.34
5 aXLDmanHepp 5.10 4.05 4.11 4.33 ? 4.22 ?
4,0,0 xXEtN
4,0 P
4 P
aXKdop
1H/13C HSQC data:
Linkage Residue C1/H1 C2/H2 C3/H3 C4/H4 C5/H5 C6/H6 C7/H7
5,3,2,2,4,4,3,2 Ac
5,3,2,2,4,4,3 bDGalpN 104.3/4.70 53.4/4.02 71.7/3.82 68.6/4.02 ?/? ?/?
5,3,2,2,4,4 aDGalp 101.3/5.00 ?/3.97 79.7/4.05 69.8/4.33 ?/? ?/?
5,3,2,2,4 bDGalp 104.3/4.59 71.7/3.68 72.8/3.85 78.3/4.14 76.3/3.88 ?/?
5,3,2,2 bDGlcp 102.6/4.77 74.0/3.47 75.4/3.77 79.7/3.76 75.5/3.67 64.1/3.88-4.07
5,3,2,3,0 xXEtN 62.5/4.29 40.4/3.37
5,3,2,3 P
5,3,2 aXLDmanHepp 100.7/5.18 77.7/4.46 75.3/4.42 ?/4.13 ?/? ?/? ?/?
5,3,6,0 xXEtN 61.5/4.24 40.4/3.31
5,3,6 P
5,3 aXLDmanHepp 99.5/5.75 79.7/4.37 ?/? ?/? ?/? 75.6/4.66 ?/?
5,4,6,0 xXCho 60.1/4.46 66.5/3.70 55.0/3.23
5,4,6 P
5,4 bDGlcp 104.2/4.60 74.0/3.47 77.0/3.53 75.4/3.66 75.6/3.61 65.2/4.23-4.34
5 aXLDmanHepp 97.6/5.10 ?/4.05 ?/4.11 74.3/4.33 ?/? ?/4.22 62.8/?
4,0,0 xXEtN
4,0 P
4 P
aXKdop
report error
Found 1 record.
Displayed record 1
]; epiglottitis [ICD11: CA06.1 
ki.se (E. K. H. Schweda)