TABLE 1.

MS data and proposed compositions for intact LOS of C. jejuni strain MF6 based on MS and MS/MS analyses

m/z of observed ionMolecular mass (Da)Proposed compositions
[M-4H]4−[M-3H]3−ObservedCalculatedaSialylation and O modification in corebPhosphorylation in lipid AAcylation in lipid A
1,015.91,354.84,067.54,067.3Neu5Ac1PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 1O-(C14:0), 1O-(C16:0)
1,023.11,364.84,096.94,095.3Neu5Ac1PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,037.41,383.34,153.34,152.3Gly·Neu5Ac1PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,054.01,405.64,219.94,218.3Neu5Ac1PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,088.91,451.94,359.24,358.5Neu5Ac2PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 1O-(C14:0), 1O-(C16:0)
1,096.01,461.44,387.94,386.5Neu5Ac2PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,103.31,471.44,417.24,415.5Gly·Neu5Ac2PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 1O-(C14:0), 1O-(C16:0)
1,107.01,476.04,431.84,428.5Ac·Neu5Ac2PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,110.31,480.64,445.24,443.5Gly·Neu5Ac2PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,119.61,493.24,482.44,481.5Neu5Ac2PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 1O-(C14:0), 1O-(C16:0)
1,121.51,495.04,489.34,485.5Ac·Gly·Neu5Ac2PPEtn, P3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,126.81,502.54,511.14,509.5Neu5Ac2PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,133.71,512.04,538.94,538.6Gly·Neu5Ac2PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 1O-(C14:0), 1O-(C16:0)
1,137.51,517.04,554.34,551.5Ac·Neu5Ac2PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,141.01,521.54,568.04,566.6Gly·Neu5Ac2PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
1,152.01,536.04,611.84,609.7Ac·Gly·Neu5Ac2PPEtn, PPEtn3 N-(3-OH-C14:0), 1 O-(3-OH-C14:0), 2O-(C16:0)
  • a Isotope-averaged mass units were used for calculation of molecular mass values based on the following proposed compositions: for hexose (Hex), 162.14; for HexNAc, 203.19; for Hep, 192.17; for 3-deoxy-d-manno-oct-2-ulosonic acid (KDO), 220.18; for P, 79.98; for PEtn, 123.05; for Neu5Ac, 291.26; for glycine (Gly), 57.05; for Ac, 42.03; for HexN, 161.07; for HexN3N, 160.18; for 3-OH-C14:0, 226.36; and for C16:0, 238.41; H2O, 18.01.

  • b All the glycoforms contain a conserved structure: Hex4·HexNAc1·Hep2·PEtn1·KDO2.