Structural analysis of a unique species of Lipid A from Burkholderia pseudomallei by mass spectrometry

摘要

MALDI-MS was used to structurally characterize lipid A molecules from B. pseudomallei and B.thailandensis by using 6-aza-2-thiothymine (ATT) as matrix. Partial and complete deacylation studies were performed using ammonium hydroxide and methylamine respectively. Tandem mass spectrometry experiments were performed on lipid A samples and deacylated lipid A samples. From the data obtained by deacylation studies and MS/MS experiments, Lipid A from B.pseudomallei likely contains a disaccharide backbone with two phosphates, two arabinoses and varying length of acyl chains. Structure of lipid A ion with m/z 1580.040 was proposed and further studies are needed to confirm the structure. Future work will involve LC-MS and NMR experiments to confirm the structures.