title: A method for the solubilization of a (1----3)-beta-D-glucan isolated from Saccharomyces cerevisiae.
abstract: This report describes a method for the solubilization of a micro-particulate beta-D-glucan. Insoluble glucan is dissolved in methyl sulfoxide and urea (8M) and partially phosphorylated at 100 degrees. The resulting water-soluble product is called glucan phosphate. The conversion rate is 70%, and the preparation is endotoxin free as determined by the Limulus lysate procedure. Glucan phosphate is composed of 34.66% C, 6.29% H, 42.83% O, and 2.23% P and has a repeating-unit empirical formula of (C6H10O5)7.PO3H2, indicating a phosphate group substitution on every seventh glucose subunit. Molecular-weight averages, polydispersity, and intrinsic viscosity were determined by aqueous high-performance size-exclusion chromatography (s.e.c.) with on-line, multi-angle laser light scattering (m.a.l.l.s.) photometry and differential viscometry (d.v.). Two polymer peaks were resolved. Peak 1 (Mw = 3.57 x 10(6) daltons), represents approximately 2% of the total polymers, while peak 2 (Mw = 1.10 x 10(5) daltons) comprises approximately 98% of polymers. 13C- and 31P-n.m.r. spectroscopy confirmed the beta-1,3 interchain linkage and the presence of a phosphate group. In solution, glucan phosphate polymers self-associate in a triple-helical arrangement. The ability to prepare a immunologically active, non-toxic, water-soluble beta-D-glucan preparation will greatly enhance the clinical utility of this class of compounds.
authors.affiliation: Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112.
authors.forename: D L
authors.initials: DL
authors.lastname: Williams
authors.forename: R B
authors.initials: RB
authors.lastname: McNamee
authors.forename: E L
authors.initials: EL
authors.lastname: Jones
authors.forename: H A
authors.initials: HA
authors.lastname: Pretus
authors.forename: H E
authors.initials: HE
authors.lastname: Ensley
authors.forename: I W
authors.initials: IW
authors.lastname: Browder
authors.forename: N R
authors.initials: NR
authors.lastname: Di Luzio
mesh_terms: D004339:Drug Compounding / Q000379:methods*; D005069:Evaluation Studies as Topic; D005936:Glucans / Q000737:chemistry* / Q000276:immunology; D007155:Immunologic Factors / Q000737:chemistry*; D008968:Molecular Conformation; D010766:Phosphorylation; D012441:Saccharomyces cerevisiae / Q000737:chemistry*; D012995:Solubility; D013403:Sugar Phosphates / Q000138:chemical synthesis
chemical_list: D005936:Glucans; D007155:Immunologic Factors; D013403:Sugar Phosphates