Lipid composition of Helicobacter pylori

In H. pylori, we examined the composition of total lipids. In thin-layer chromatography, three kinds of glycolipids were detected, which were named as G-1, G-2 and G-3. G-3 contained phosphates in addition to sugars. Total lipids consisted of 6.0% neutral lipids (weight %), 20.6% glycolipids (G-1, G-2) and 73.4% phospholipids (including G-3). Total glycolipids were approximately 25% of total lipids. After methanolysis, cholesterol was detected in the hexane extractable fraction and glucose was detected by GLC in the methanol fraction after trimethylsilylation, in all glycolipids. Therefore, these glycolipids are cholesteryl glycosides. Cholesteryl glycosides are found very rarely in bacteria, and have been detected only in a few species of mycoplasmas and spirochetes.