The structure of Cryptococcus neoformans galactoxylomannan contains β-D-glucuronic acid

The structure of galactoxylomannan, a capsular polysaccharide from the opportunistic yeast Cryptococcus neoformans, was re-examined by NMR spectroscopy and GC-MS. The residue that is 3-linked to the side chain galactose and was previously assigned as beta-D-xylose [Vaishnav, V. V.; Bacon. B. E.; O'Neill, M.; Cherniak, R. Carbohydr. Res. 1998, 306, 315-330] was determined to be P-D-glucuronic acid. A revised structure for this polymer is presented, along with a proposal that this compound be termed glucuronoxylomannogalactan (GXMGal). (C) 2009 Elsevier Ltd. All rights reserved.