A Study of Saccharomyces cerevisiae Cell Wall Glucans

Stefan Kwiatkowski^1,2, Ursula Thielen¹, Phyllis Glenney¹ and Colm Moran¹
¹ Alltech Biotechnology Center, 3031 Catnip Hill Pike, Nicholasville KY 40356, USA.
² Corresponding Author. E-mail: skwiatkowski@alltech.com.

J. Inst. Brew. 115(2), 151–158, 2009 | VIEW ARTICLE

ABSTRACT
Much research has been carried out over the years examining cell wall glucans from Saccharomyces cerevisiae and this study further examines aspects of the binding of (1→4)-α-D-glucan in the yeast cell wall, using a number of isolation techniques as well as monoclonal antibodies able to recognize a mixed (1→4)- α-D-glucan/(1→6)-β-D-glucan. Extraction of purified glucan, from S. cerevisiae cell wall, with 0.1N HCl, at 80°C for 6 h, released into the solution (1→4)-α-D-glucan and (1→6)-β-Dglucan as the major polysaccharides, along with an insoluble pellet highly enriched in (1→3)-β-D-glucan. The released (1→4)-α-D-glucan was composed of a high molecular size >100 kDa fraction (7.2% w/w) and a medium 5–50 kDa polysaccharide (10.2% w/w), with the (1→4)-α-D-glucan covalently bound to the (1→6)-β-D-glucan. The average molar ratio of the α:β glucan was 47: 53 in this mixed polysaccharide. The structure of this polysaccharide was different from the structure of plant starch or animal glycogen as monoclonal antibodies specific to yeast (1→4)-α-D-glucan/(1→6)-β-D-glucan did not recognize the plant starch or animal glycogen standards.

Key words:
(1→4)-α-D-glucan, 1→6)-β-D-glucan, glucan specific antibodies, NMR, Saccharomyces cerevisiae, yeast cell wall.