Oxford, UK: Blackwell Science Ltd. on behalf of the Federation of European Biochemical Societies
The chemical structure of the phosphorylated carbohydrate backbone of the lipopolysaccharide (LPS) from Acinetobacter baumannii strain ATCC 19606 was investigated by chemical analysis and NMR spectroscopy of oligosaccharides obtained after deacylation or mild acid hydrolysis. From the combined information the following carbohydrate backbones can be deduced: where R1 = H and R2 = α-Glcp-(1→2)-β-Glcp-(1→4)-β-Glcp-(1→4)-β-Glcp-(1 as major and R1 = Ac and R2 = H as minor products. All monosaccharides are d-configured. Also, smaller oligosaccharide phosphates were identified that are thought to represent degradation products of the above structures
13C NMR data:
Linkage Residue C1 C2 C3 C4 C5 C6 C7 C8
0,6,6,4 aXKdop 176.0 103.4 35.2 66.7 67.6 72.8 71.6 63.7
0,6,6,5,4,3,4,4,2 aDGlcp 98.2 72.1 73.5 70.1 72.4 61.1
0,6,6,5,4,3,4,4 bDGlcp 102.2 77.1 75.3 70.4 76.7 61.4
0,6,6,5,4,3,4 bDGlcp 103.1 73.9 74.8 76.6 75.7 60.8
0,6,6,5,4,3 bDGlcp 102.2 73.5 74.5 79.1 75.7 60.6
0,6,6,5,4 bL4dthrHexp4enNA 92.2 51.3 71.6 104.4 148.4 168.7
0,6,6,5,7 bDGlcpN 98.1 56.6 72.9 70.7 76.7 61.5
0,6,6,5 aXKdop 176.0 101.8 30.0 71.8 63.1 71.0 77.1 60.6
0,6,6 aXKdop 176.1 100.8 35.1 73.4 70.0 73.3 70.3 64.6
0,6,4 P
0,6 bDGlcpN 100.4 56.4 72.8 75.1 74.7 63.2
0 aDGlcpN 91.6 55.4 70.4 70.3 73.4 70.4
P
1H NMR data:
Linkage Residue H1 H2 H3 H4 H5 H6 H7 H8
0,6,6,4 aXKdop - - 1.70-2.07 4.01 3.96 3.69 3.96 3.70-3.89
0,6,6,5,4,3,4,4,2 aDGlcp 5.34 3.51 3.72 3.42 4.04 3.75-3.77
0,6,6,5,4,3,4,4 bDGlcp 4.63 3.49 3.56 3.41 3.44 3.70-3.89
0,6,6,5,4,3,4 bDGlcp 4.50 3.33 3.64 3.74 3.63 3.85-3.97
0,6,6,5,4,3 bDGlcp 4.72 3.33 3.64 3.64 3.63 3.81-3.97
0,6,6,5,4 bL4dthrHexp4enNA 5.47 3.76 4.66 5.98 - -
0,6,6,5,7 bDGlcpN 4.97 3.12 3.66 3.45 3.52 3.72-3.92
0,6,6,5 aXKdop - - 2.30-2.91 4.87 4.43 4.29 4.13 3.92-3.92
0,6,6 aXKdop - - 1.92-2.33 3.95 4.48 3.67 3.86 3.60-3.86
0,6,4 P
0,6 bDGlcpN 4.85 3.03 3.83 3.75 3.73 3.39-3.68
0 aDGlcpN 5.63 3.39 3.86 3.63 4.12 3.73-4.26
P
1H/13C HSQC data:
Linkage Residue C1/H1 C2/H2 C3/H3 C4/H4 C5/H5 C6/H6 C7/H7 C8/H8
0,6,6,4 aXKdop 35.2/1.70-2.07 66.7/4.01 67.6/3.96 72.8/3.69 71.6/3.96 63.7/3.70-3.89
0,6,6,5,4,3,4,4,2 aDGlcp 98.2/5.34 72.1/3.51 73.5/3.72 70.1/3.42 72.4/4.04 61.1/3.75-3.77
0,6,6,5,4,3,4,4 bDGlcp 102.2/4.63 77.1/3.49 75.3/3.56 70.4/3.41 76.7/3.44 61.4/3.70-3.89
0,6,6,5,4,3,4 bDGlcp 103.1/4.50 73.9/3.33 74.8/3.64 76.6/3.74 75.7/3.63 60.8/3.85-3.97
0,6,6,5,4,3 bDGlcp 102.2/4.72 73.5/3.33 74.5/3.64 79.1/3.64 75.7/3.63 60.6/3.81-3.97
0,6,6,5,4 bL4dthrHexp4enNA 92.2/5.47 51.3/3.76 71.6/4.66 104.4/5.98
0,6,6,5,7 bDGlcpN 98.1/4.97 56.6/3.12 72.9/3.66 70.7/3.45 76.7/3.52 61.5/3.72-3.92
0,6,6,5 aXKdop 30.0/2.30-2.91 71.8/4.87 63.1/4.43 71.0/4.29 77.1/4.13 60.6/3.92-3.92
0,6,6 aXKdop 35.1/1.92-2.33 73.4/3.95 70.0/4.48 73.3/3.67 70.3/3.86 64.6/3.60-3.86
0,6,4 P
0,6 bDGlcpN 100.4/4.85 56.4/3.03 72.8/3.83 75.1/3.75 74.7/3.73 63.2/3.39-3.68
0 aDGlcpN 91.6/5.63 55.4/3.39 70.4/3.86 70.3/3.63 73.4/4.12 70.4/3.73-4.26
P