Division of Structural Biochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Borstel, Germany
The rough-type lipopolysaccharide (LPS) of the phytopathogenic bacterium Xanthomonas campestris pv. campestris B 100 was isolated utilizing the hot phenol-water method and successively de-acylated by treatment with hydrazine and hot potassium hydroxide. Four compounds were separated by preparative high-performance anion-exchange chromatography and studied by sugar analysis and by 1D and 2D homonuclear and heteronuclear (1)H-, (13)C- and (31)P-NMR spectroscopy as well as ESI FT-MS. The two main products were a heptasaccharide and a pentasaccharide of the structures α-D-Manp-(1→3)-α-D-Manp-(1→4)-β-D-Glcp-(1→4)-α-D-Manp-3P-(1→5)-α-Kdo-(2→6)-β-D-GlcpN-4P-(1→6)-α-D-GlcpN-1P (1) and β-D-Glcp-(1→4)-α-D-Manp-3P-(1→5)-α-Kdo-(2→6)-β-D-GlcpN-4P-(1→6)-α-D-GlcpN-1P (2), respectively. The products in smaller amounts were a heptasaccharide and pentasaccharide possessing the above structures plus a phosphate group at C-4 of the Kdo residue (compounds 3 and 4). Both, heptasaccharide 1 and pentasaccharide 2 were able to induce an oxidative burst in cell cultures of the non-host plant tobacco
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6 C7 C8
0,6,6,5,4,4,3 aDManp 103.38 71.15 71.49 68.00 74.53 62.12
0,6,6,5,4,4 aDManp 102.23 71.05 78.85 67.07 75.03 62.12
0,6,6,5,4 bDGlcp 102.57 74.31 77.29 77.31 75.87 61.98
0,6,6,5,3 P
0,6,6,5 aDManp 101.02 70.58 73.48 76.09 75.73 61.20
0,6,6 aXKdop ? 101.14 36.07 66.73 76.33 72.92 70.12 64.51
0,6,4 P
0,6 bDGlcpN 104.35 57.17 77.32 74.17 75.48 64.10
0 aDGlcpN 95.63 56.71 74.80 71.05 72.20 69.86
P
1H NMR data:
Linkage Residue H1 H2 H3 H4 H5 H6 H7 H8
0,6,6,5,4,4,3 aDManp 5.150 4.092 3.907 3.671 3.792 3.794-3.913
0,6,6,5,4,4 aDManp 5.289 4.230 3.956 3.803 3.765 3.796-3.929
0,6,6,5,4 bDGlcp 4.641 3.375 3.669 3.610 3.585 3.775-3.929
0,6,6,5,3 P
0,6,6,5 aDManp 5.121 4.128 4.584 4.110 4.140 3.834-3.986
0,6,6 aXKdop - - 1.887-2.102 4.182 4.227 3.867 4.056 3.778-3.936
0,6,4 P
0,6 bDGlcpN 4.437 2.738 3.605 3.734 3.683 3.581-3.730
0 aDGlcpN 5.412 2.695 3.644 3.486 4.071 3.879-4.239
P
1H/13C HSQC data:
Linkage Residue C1/H1 C2/H2 C3/H3 C4/H4 C5/H5 C6/H6 C7/H7 C8/H8
0,6,6,5,4,4,3 aDManp 103.38/5.150 71.15/4.092 71.49/3.907 68.00/3.671 74.53/3.792 62.12/3.794-3.913
0,6,6,5,4,4 aDManp 102.23/5.289 71.05/4.230 78.85/3.956 67.07/3.803 75.03/3.765 62.12/3.796-3.929
0,6,6,5,4 bDGlcp 102.57/4.641 74.31/3.375 77.29/3.669 77.31/3.610 75.87/3.585 61.98/3.775-3.929
0,6,6,5,3 P
0,6,6,5 aDManp 101.02/5.121 70.58/4.128 73.48/4.584 76.09/4.110 75.73/4.140 61.20/3.834-3.986
0,6,6 aXKdop 36.07/1.887-2.102 66.73/4.182 76.33/4.227 72.92/3.867 70.12/4.056 64.51/3.778-3.936
0,6,4 P
0,6 bDGlcpN 104.35/4.437 57.17/2.738 77.32/3.605 74.17/3.734 75.48/3.683 64.10/3.581-3.730
0 aDGlcpN 95.63/5.412 56.71/2.695 74.80/3.644 71.05/3.486 72.20/4.071 69.86/3.879-4.239
P