A LIPID INTERMEDIATE IN MANNAN BIOSYNTHESIS IN YEAST

Lipid intermediates in the synthesis of bacterial cell wall polysaccharides (1,2,3) have been identified as C55-polyisoprenol to which the cell wall precursor is linked either via a pyrophosphate bond (4,5) or a phosphodiester bridge (3). Recently Behrens and Cabib (6) have shown that a particulate enzyme preparation from Saccharomyces carlsbergensis incorporates mannose from GDP-mannose into mannan. The authors did not obtain, however, any indication for the involvement of a lipid intermediate in mannan biosynthesis in yeast. The results reported here indicate that also in yeast (S. cerevisiae) as in M. lysodeikticus (3) a lipophilic mannosyl intermediate is the immediate precursor for mannan biosynthesis. Recently very similar observations have also been made for a polysaccharide synthesizing in vitro system of higher plants (Kauss, personal communication). © 1969.