Structural studies of the antigen III cell wall polysaccharide of Trichosporon domesticum

Cell wall and soluble polysaccharides that reacted with Trichosporon domest icum factor III serum were isolated from the type strain of T. domesticum. The fractions contained O-acetyl groups, which contributed to the serologic al reactivity. The antigenic structure was characterized by chromatographic and spectroscopic methods. The polysaccharide has an alpha-(1 --> 3)-D-man nan backbone with hetero-oligosaccharide side chains consisting of a 2-O-su bstituted beta -D-glucuronic acid residue bound to O-2 of the mannose resid ue, beta -D-xylopyranosyl residues located in the middle of the side chain, and a nonreducing terminal alpha -L-arabinopyranosyl residue bound to O-4 of xylose. The mannan backbone is O-acetylated at O-6 of the mannose residu es. (C) 2001 Elsevier Science Ltd. All rights reserved.