TABLE 4.
NMR chemical shifts assignments of the resonances of the LOS from BmEPR and Bm_wbkD
1H, 13C, and 31P NMR chemical shifts (ppm) at 25 °C and pD 8 of the resonances of the components of the deacylated LOS from BmEPR and Bm_wbkD and inter-residue correlations from the 1H,13C HMBC spectra. The different oligosaccharide components of the samples differ in the presence/absence of residues E (Glc) and/or I (GlcN) (see Fig. 4). For residue A, 3JP,H1 = 8.3 Hz, 2JP,C1 = ∼4.5 Hz, and 3JP,C2 = ∼7.4 Hz. Resonances from H1 and C1 in residue G* are found at 4.626 and 102.12 ppm, respectively (overlapping with H1 and C1 in residue G**). Resonances from H3 and C3 in F** are found at 4.129 and 80.07 ppm (overlapping with H3 and C3 in residue F). ND means not determined. NR means not resolved.
| Sugar residues |
1H/13C |
31P | HMBC correlations (from anomeric atom) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3a | 3b | 4 | 5 | 6a | 6b | 7 | 8a | 8b | |||||
| →6)-α-d-GlcpN3N1P | A | 5.419 | (3.2) | 2.898 | 3.126 | 3.503 | 4.127 | 3.738 | 4.290 | 2.5 | |||||
| 94.28 | {174} | 54.76 | 54.87 | 69.25 | 72.48 | 70.34 | |||||||||
| →6)-β-d-GlcpN3N4P-(1→ | B | 4.535 | (8.0) | 2.753 | 3.112 | 3.764 | 3.724 | 3.472 | 3.782 | 3.1 | C6, A | ||||
| 103.81 | {162} | 55.61 | 58.63 | 71.44 | 76.39 | 63.66 | H6a, A | ||||||||
| →4,5)-α-Kdop-(2→ | C | 2.010 | 2.081 | 4.250 | 4.236 | 3.721a | 3.738a | 3.717 | 3.890 | ||||||
| 175.68a | 100.45 | 35.25 | 70.54 | 74.36 | 72.80a | 70.46a | 64.27 | H6a, B | |||||||
| →4)-α-Kdop-(2→ (without residue E) | C* | 1.996 | 2.099 | 4.177 | 4.254 | ND | ND | ND | ND | ||||||
| ND | 100.45 | 35.25 | 74.96 | 74.36 | ND | ND | ND | ||||||||
| →4)-α-Kdop-(2→ | D | 1.863 | 2.324 | 4.205 | 4.276 | 3.721 | 3.987 | 3.793 | 3.996 | ||||||
| 175.34a | 101.18 | 33.25 | 76.22 | 66.68 | 72.83 | 70.76 | 63.95 | H4, C | |||||||
| α-Kdop-(2→ (without residue E) | D* | 1.802 | 2.161 | 4.042 | 4.022 | 3.702 | 3.994 | 3.782 | 3.983 | ||||||
| ND | 101.74 | 35.29 | 66.77 | 67.37 | 72.96 | 71.03 | 64.85 | ||||||||
| β-d-Glcp-(1→ | E | 4.609 | (7.9) | 3.299 | 3.520 | 3.426 | 3.480 | 3.747 | 3.915 | C4, D | |||||
| 102.69 | {162} | 73.86 | 76.30 | 70.30 | 76.53 | 61.36 | H4, D | ||||||||
| →3)-α-d-Manp-(1→ | F | 5.268 | (NR) | 4.312 | 4.129 | 3.847 | 4.130 | ∼3.887 | C5, C | ||||||
| 101.54 | {173} | 68.71 | 80.07 | 65.79 | 73.62 | 61.66 | H5, C | ||||||||
| →3)-α-d-Manp-(1→ (without residue E) | F* | 5.275 | 4.310 | 4.089 | 3.874 | 4.089 | ∼3.887 | ||||||||
| 101.40 | {173} | 68.90 | 80.47 | 65.66 | 73.41 | 61.66 | H5, C* | ||||||||
| →4,6)-β-d-GlcpN-(1→ | G | 4.627 | (8.2) | 2.758 | 3.584 | 3.709 | 3.844 | 3.891 | 4.272 | C3, F | |||||
| 101.91 | {165} | 56.77 | 75.20 | 80.26 | 74.25 | 68.89 | H3, F | ||||||||
| →4,6)-β-d-GlcpN-(1→ (without residue I) | G** | 4.626 | (8.30) | 2.756 | 3.595 | 3.736 | 3.844 | 3.891 | 4.272 | ||||||
| 102.12 | {165} | 56.87 | 74.90 | 79.12 | 74.25 | 68.89 | H3, F** | ||||||||
| →6)-β-d-GlcpN-(1→ | H | 4.442 | (8.1) | 2.748 | 3.405 | 3.467 | 3.668 | 3.851 | 4.267 | C4, G | |||||
| 104.03 | {163} | 57.45 | 76.01 | 70.48 | 75.70 | 69.66 | H4, G | ||||||||
| β-d-GlcpN-(1→ (without residue I) | H** | 4.440 | 2.727 | 3.405 | 3.480 | 3.489 | 3.752 | 3.934 | C4, G** | ||||||
| 103.48 | {163} | 57.59 | 76.31 | 70.41 | 77.03 | 61.46 | H4, G** | ||||||||
| β-d-GlcpN-(1→ | I | 4.426 | (8.1) | 2.682 | 3.384 | 3.464 | 3.460 | 3.752 | 3.934 | C6, H | |||||
| 104.18 | {163} | 57.26 | 76.33b | 70.55 | 76.87 | 61.62 | H6a, H | ||||||||
| β-d-GlcpN-(1→ | J | 4.465 | (8.2) | 2.723 | 3.373 | 3.409 | 3.460 | 3.748 | 3.913 | C6, G | |||||
| 103.77 | {162} | 57.16 | 76.30b | 70.55 | 76.87 | 61.57 | |||||||||
a Tentative assignments are shown.
b Assignments may be interchanged.