The structure of bactoprenol, a lipid formed by lactobacilli from mevalonic acid

Abstract

The name "bactoprenol" has been given to the most abundant lipid formed by three species of lactobacilli from mevalonic acid. A method for the preparation of pure bactoprenol is described. The thin-layer chromatographic properties of bactoprenol and of its acetylated and hydrogenated derivatives resembled those of dolichol. Analysis by mass spectrometry and by nuclear magnetic resonance showed that the molecule is formed by condensation of 10 unsaturated isoprene units and 1 saturated isoprene unit. Its molecular weight is 768 and it has 10 double bonds/molecule. Infrared spectroscopy and the uptake of acetyl groups indicated that the molecule contains a hy-droxyl group. It is concluded that bactoprenol is a C55 isoprenoid alcohol.