Insights into the Physicochemical Characterization, Chemistry, Structure and Synthesis of (1 →3,1 →6)- β-Glucans
Pp. 29-82 (54)
David L. Williams, Douglas W. Lowman, Mike Reale and Harry E. Ensley
The ability of yeast cell wall fractions to stimulate immunity and increase
resistance to disease is well documented. For more than fifty years we have known that the
immune stimulating activity of yeast cell walls is primarily due to the (1→3,1→6)-β-Dglucans
(hereafterβ-glucans), which are important structural components of the cell wall.
Evidence indicates that the bioactivity of β -D-glucans is intimately linked to the structure
and physicochemical properties of these complex carbohydrate polymers. Virtually all
natural product β -glucan isolates are a distribution of glucan polymers with varying
polymer lengths, varying molecular weight and, in most cases, differences in branching
frequency, length of side chain branches and solution conformation. This level of structural
complexity and variability presents a number of challenges to investigators attempting to
understand the chemistry and biology of glucans. Herein, we describe the physicochemical
analysis, structural chemistry and quantification of glucans derived from natural sources.
This work has not only advanced our understanding of these intriguing and medically
important biomolecules, but it has also provided a foundation for the development of
methods for the total organic synthesis of bioactive β -glucan oligosaccharides. The
availability of synthetic β -glucan oligosaccharides of defined structure and composition
may herald a new era in the field of glucan biology.
Synthesis, molecular weight, polymers, analysis, oligosaccharides,
glucan, natural product, carbohydrate polymers, fungi, cell wall, organic
synthesis, de novo synthesis, oligosaccharides, oligomers, gel permeation
chromatography, molecular weight, nuclear magnetic resonance spectroscopy,
structure, gas chromatography/mass spectrometry, linkage analysis, bioactivity,
Dectin-1, receptor, binding affinity.
Department of Surgery, Quillen College of Medicine, East Tennessee State University, Johnson City, Tennessee 37614, USA