The biosynthesis of oligosaccharide-lipids. Formation of an alpha-1,2-mannosyl-mannose linkage

J Biol Chem. 1980 May 10;255(9):4170-5.

Abstract

An enzyme present in rabbit liver microsomes has been found to catalyze mannosyltransfer from GDP-mannose to exogenously added oligosaccharide-lipid acceptor resulting in the formation of an alpha-1,2-mannosyl-mannose linkage. Several lines of evidence suggest that the product is a heptasaccharide containing a single 1,6-linked branched glycosyl unit with 65% of the newly added mannosyl units in a terminal nonreducing position. The enzyme has been solubilized with non-ionic detergents and was partially purified on DEAE-cellulose and hydroxylapatite. The partially purified enzyme no longer catalyzed the formation of dolichol-P-mannose indicating a direct transfer from GDP-mannose to oligosaccharide-lipid acceptor.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Glycolipids / biosynthesis*
  • Guanosine Diphosphate Mannose
  • Hexosyltransferases / metabolism*
  • Kinetics
  • Mannosyltransferases / isolation & purification
  • Mannosyltransferases / metabolism*
  • Microsomes, Liver / enzymology*
  • Oligosaccharides / biosynthesis*
  • Rabbits

Substances

  • Glycolipids
  • Oligosaccharides
  • Guanosine Diphosphate Mannose
  • Hexosyltransferases
  • Mannosyltransferases