Table III.
800-MHz 1H and 13C NMR parameters observed for the SCWP released by HF treatment of B. cereus G9241 cell wallsa
| Compound glycose residue | JC1, H1 (Hz) |
δH ppm |
|||||
|---|---|---|---|---|---|---|---|
|
δC ppmb | |||||||
| 1 | 2 | 3 | 4 | 5 | 6 | ||
| Native polysaccharide | |||||||
| A →3,4,6)-α-d-GlcpNAc-(1→ | 178.7 | 5.79/96.61 | 4.15/52.79 | 3.99/75.56 | 4.07/77.70 | 3.86/69.98 | 4.14/4.14/68.0 |
| A′ →3,4,6)-α-d-GlcpNAc-(1→ | 180.0 | 5.76/96.61 | 4.16/52.79 | 4.00/77.30 | 4.10/77.70 | 3.81/69.98 | 3.98/3.98/67.6 |
| B α-d-Galp-(1→ | 178.7 | 5.68/97.91 | 3.80/69.54 | 3.71/70.19 | 3.98/69.76 | 3.81/71.70 | ≈3.72/3.72/61.4 |
| B′ α-d-Galp-(1→ | 177.3 | 5.63/98.33 | 3.80/69.54 | 3.72/70.19 | 3.99/69.76 | 3.81/71.70 | ≈3.72/3.72/61.4 |
| C α-d-Galp-(1→ | 177.0 | 5.55/99.40 | 3.76/69.76 | 3.72/70.19 | 3.99/69.76 | 3.83/71.70 | ≈3.83/3.74/61.6 |
| C′ α-d-Galp-(1→ | 177.1 | 5.52/99.62 | 3.76/69.76 | 3.71/70.19 | 3.98/69.76 | 3.86/71.70 | ≈3.83/3.74/61.6 |
| D′ →4,6)-α-d-GlcpNAc-(1→ | 176.5 | 5.24/98.76 | 3.91/53.86 | 3.86/71.69 | 3.63/79.86 (D′) and 3.72/79.63 (D′′) | 3.77/71.69 | 3.95/3.93/67.6 |
| D →3,4,6)-α-d-GlcpNAc-(1→ | 177.0 | 5.21/99.19 | 4.08/53.43 | 4.01/75.72 | 4.03/77.06 | 3.96/71.47 | 4.14/4.13/67.4 |
| F α-d-Galp-(1→ | 172.6 | 5.05/101.56 | 3.77/68.68 | 3.65/70.19 | 3.93/69.97 | 4.15–4.20/72.13 | 3.73/3.73/62.46 |
| G →3,4)-β-d-ManpNAc-(1→ | 165.1 | 4.91/99.40 | 4.65/54.51 | 4.24/80.28 | 4.10/77.27 | 3.52/75.56 | 3.89/3.91/60.7 |
| G′ →4)-β-d-ManpNAc-(1→ | 165.0 | 4.90/100.04 | 4.50/54.51 | 4.05–4.10/73.41 | 3.67–3.73/76.20 | 3.51/75.35 | 3.91/3.82/61.2 |
| H →3,4)-β-d-GlcpNAc-(1→ | 159.4 | 4.65/101.54 | 3.90–3.91/55.15 | 3.90/75.98 | 4.10/77.31 | 3.52/75.99 | 3.74/3.92/60.7 |
| Ic β-d-Galp-(1→ | 163.7 | 4.44/103.48 | 3.54/71.70 | 3.64/73.30 | 3.94/69.33 | 3.66/76.21 | 3.75/3.82/61.8 |
The intact polysaccharide was purified by Superose size exclusion chromatography and subjected to NMR analysis.
a800 MHz spectra measured at 25°C in D2O relative to internal DSS (δH 0.00 ppm).
bCarbon δC obtained from 1H-13C HSQC spectra; carbonyl δC from the HMBC spectra.
cAdditional heterogeneity exists for residue I; the major spin system is listed here, and less abundant systems (I′, I′′, etc.) are listed in Supplementary data.
Additional signals. Pyruvate: C1, (C = O) δ 177.04, (C2) δ 100.70, (C3) CH3 δ 25.29, CH3 δ 1.55; N-acetyl: βGlcNAc, C = O δ 174.46, CH3 δ 22.93, CH3 δ 2.08; αGlcNAc, C = O δ 176.20, CH3 δ 20.99, CH3 δ 2.08; βManNAc, C = O δ 175.97, CH3 δ 22.93, CH3 δ 2.03; residue E (α-reducing end): →3,6,4)-α-d-GlcpNAc, H1/C1 δ 5.13/91.67 (JC1,H1 171.1 Hz), H2/C2 δ 4.06/53.5, H3 δ 3.94, H4 δ 3.83, H5 δ 3.75, H6 not assigned; (β-reducing end): H1/C1 δ 4.74/95.32, H2/C2 δ 3.79/56.12, H3/H4/H5 = δ 4.07/3.87/3.52; H6 not assigned.