TABLE 2.
Proposed structures for the various molecular ions observed during MALDI-TOF MS analysis of the HF-PS from B. cereus ATCC 10987
The proposed structures are consistent with the glycosyl composition, linkage, and NMR data.
| Repeat units | Proposed structure | Observed [M + Na]+ ion |
|---|---|---|
| R1 + 1 | [ManNAc-GlcNAc(Gal)GalNAc]-ManNAc | 1015.3 |
| R1 + 2 | [ManNAc-GlcNAc-(GalGalNAc]-ManNAc-GlcNAc | 1218.4 |
| R2 + 0 | [ManNAc-GlNAc-(Gal)GalNc]-[ManNAc-GlcNc-(Gal)GalNAc] | 1583.5 |
| R2a + 0 + 1Ac | [(Ac)ManNAc-lcNAc-(Gal)GalAc]-[ManNAc-GlcAc-(Gal)GalNAc] | 1625.5 |
| R2a + 0 + 2Ac | [(Ac)ManNAc-GlNAc-(Gal)GalNc]-[(Ac)ManNAc-GcNAc-(Gal)GalNAc] | 1667.5 |
| R2 + 1 | [ManNAc-GlcNA-(Gal)GalNAc]-[anNAc-GlcNAc-(al)GalNAc]-ManNAc | 1786.5 |
| R2 + 2 | [ManNAc-GlcNAc-(Gl)GalNAc]-[ManAc-GlcNAc-(Gal)alNAc]-ManNAc-GlcNAc | 1990.6 |
| R3 + 0 | [ManNAc-GlcNAc-(Gal)GalNc]-[ManNAc-GlNAc-(Gal)GalNAc][ManNAc-GlcNAc-(Gal)GalNAc] | 2354.6 |
| R3 + 0 + 1Ac | [(Ac)ManNAc-GlcNAc-(Gal)GaNAc]-[ManNAc-GcNAc-(Gal)GalNc]-[ManNAc-GlcNAc-(Gal)GalNAc] | 2396.7 |
| R3 + 0 + 2Ac | [(Ac)ManNAc-GlcNAc-(Gal)GalNc]-[(Ac)ManNAcGlcNAc-(Gal)GalAc]-[ManNAc-GlcNAc-(Gal)GalNAc] | 2438.7 |
| R3 + 0 + 3Ac | [(Ac)ManNAc-GlcNAc-(Gal)GalNA]-[(Ac)ManNAc-GcNAc-(Gal)GalNc]-[(Ac)ManNAc-GlcNAc-(Gal)GalNAc] | 2480.6 |
a
The location of these acetyl (Ac) groups could be on any of one, two, or three of the various ManNAc residues. Rn, the number of repeating units. The number following the repeating units indicates the number of added HexNAc residues. Brackets enclose components of a single repeat unit.