Radioactive glycolipids were extracted from cells of Aureobasidium pullulanspulsed with d-[14C]glucose. Labelled, alkali-stable lipids were resolved into one neutral and two acidic fractions. The neutral fraction was stable to mild hydrolysis with acid, whereas the acidic fractions could be hydrolysed, yielding d-glucose and a series of oligosaccharides having mobilities corresponding to those of isomaltose, panose, and isopanose. Amyloglucosidase (EC 184.108.40.206) catalysed the hydrolysis of 60% of the liberated radioactive oligosaccharides to d-glucose, indicating the presence of (1?4)-a- and (1 ? 6)-a-d-glucosidic bonds. Since these lipid-linked saccharides are produced during pullulan biosynthesis in A. pullulans, it is proposed that they are intermediates in the biosynthetic pathway of that extracellular polysaccharide. A mechanism incorporating these glycolipids into a possible scheme of polysaccharide assembly is presented. © 1982 Elsevier Scientific Publishing Company.
|Number of pages||11|
|Publication status||Published - 1 May 1982|